CN101843070B - Method and apparatus for communicating over multiple networks - Google Patents

Method and apparatus for communicating over multiple networks Download PDF

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Publication number
CN101843070B
CN101843070B CN200780101295.XA CN200780101295A CN101843070B CN 101843070 B CN101843070 B CN 101843070B CN 200780101295 A CN200780101295 A CN 200780101295A CN 101843070 B CN101843070 B CN 101843070B
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tdf
time slot
grouping
time
frame
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CN101843070A (en
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于劲飞
张志刚
张俊彪
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Thomson Licensing SAS
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    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L12/00—Data switching networks
    • H04L12/28—Data switching networks characterised by path configuration, e.g. LAN [Local Area Networks] or WAN [Wide Area Networks]
    • H04L12/2854—Wide area networks, e.g. public data networks
    • H04L12/2856—Access arrangements, e.g. Internet access
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L12/00—Data switching networks
    • H04L12/28—Data switching networks characterised by path configuration, e.g. LAN [Local Area Networks] or WAN [Wide Area Networks]
    • H04L12/2854—Wide area networks, e.g. public data networks
    • H04L12/2856—Access arrangements, e.g. Internet access
    • H04L12/2869—Operational details of access network equipments
    • H04L12/2898—Subscriber equipments
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L12/00—Data switching networks
    • H04L12/28—Data switching networks characterised by path configuration, e.g. LAN [Local Area Networks] or WAN [Wide Area Networks]
    • H04L12/46—Interconnection of networks
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L12/00—Data switching networks
    • H04L12/28—Data switching networks characterised by path configuration, e.g. LAN [Local Area Networks] or WAN [Wide Area Networks]
    • H04L12/46—Interconnection of networks
    • H04L12/4633—Interconnection of networks using encapsulation techniques, e.g. tunneling

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  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Mobile Radio Communication Systems (AREA)

Abstract

A Asymmetric Data over Coaxial (ADoC) dual mode device provides support for both wired and wireless modes of operation, and can switch between these two modes periodically. In ADoC (wired) mode, the dual mode device operates as ADoC Station while in WLAN (wireless) mode, it operates as WLAN Access Point. In one particular implementation, a communication unit (3100, 3104, 3106) is configured for communicating over multiple media including a wireless medium and a wired medium, the communication unit being operable (1) in a wireless mode for communicating over a wireless medium using a wireless protocol, and (2) in a wired mode for communicating over the wired medium using a variation of the wireless protocol. The implementation also includes a switch (3104) to switch the communication unit between the wireless mode and the wired mode.

Description

The method communicating with various modes and device
Technical field
The disclosure is usually devoted to the various aspects of communication system.
Background technology
There is the communication system for user is connected with information.Such system can be used coaxial cable and wireless network.Existing system shows various limitation.
Summary of the invention
According to a total aspect, the equipment such as communication unit for example for communicating on the medium that comprises wireless medium and wire medium.This communication unit can operate in (1) wireless mode, use wireless protocols to communicate by letter on wireless medium, and (2) has ray mode, uses the modification (variation) of described wireless protocols to communicate by letter on wire medium.Equipment such as switch for example is for example configured to, by communication equipment (, described communication unit) at wireless mode and has between ray mode switch.
The aspect total according to another, a kind of method communicating on the medium that comprises wireless medium and wire medium that is included in, described communication is used with lower one or more: (1) wireless mode, uses wireless protocols to communicate by letter on wireless medium; And (2) have ray mode, use the modification of described wireless protocols to communicate by letter on wire medium.The method is included in wireless mode and has between ray mode to be switched.
The aspect total according to another, a kind of device that comprises processor readable medium, described processor readable medium is included in the instruction for communicating on the medium comprising wireless medium and wire medium of storing on described processor readable medium, described communication is used with lower one or more: (1) wireless mode, uses wireless protocols to communicate by letter on wireless medium; And (2) have ray mode, use the modification of described wireless protocols to communicate by letter on wire medium.This instruction is also at wireless mode with have between ray mode and switch.
The details of one or more embodiments is proposed in following accompanying drawing and description.Even described in a specific mode, also should know and can configure in every way or embody described embodiment.For example, embodiment can be carried out as method, or be presented as the equipment that is configured to carry out one group of operation, or be presented as that storage is for carrying out the equipment of one group of instruction operating.Consider following detailed description together with accompanying drawing and claim, it is obvious that other side and feature will become.
Brief description of the drawings
Fig. 1 illustrates the exemplary TDF access network framework of simplification.
Fig. 2 is shown in the 802.11MAC sublayer in OSI Reference Model.
Fig. 3 is shown in the embodiment of the TDF transmission entity in OSI Reference Model.
Fig. 4 illustrates the embodiment of communication pattern entrance routine.
Fig. 5 illustrates the embodiment of TDF super frame structure.
Fig. 6 illustrates the embodiment of registration (registration) routine.
Fig. 7 illustrates the embodiment of cancellation (unregistration) routine.
Fig. 8 illustrates the embodiment of survival (alive) notification routines.
Fig. 9 comprises the system diagram of the embodiment of having described TDF network.
Figure 10 comprises according to the block diagram of the embodiment of the AP of Fig. 9 and modulator-demodulator.
Figure 11 comprises the flow chart of the embodiment of uplink transmission process.
Figure 12 is included in the figure of the embodiment of mapping one to one between Ethernet grouping and WLAN grouping.
Figure 13 is included in the figure of the embodiment converting between multiple Ethernet groupings and single WLAN grouping.
Figure 14 comprises the figure of the stream of packets in the conversion of describing Figure 13.
Figure 15 comprises according to the figure of the embodiment of the EIW head of Figure 14.
Figure 16 comprises the flow chart of the embodiment of up link reception & disposal.
Figure 17 comprises the figure of the embodiment of describing decapsulation grouping.
Figure 18 comprises the figure describing according to the embodiment of the PADM of Figure 10.
Figure 19 comprises that down link transmits the flow chart of the embodiment of processing.
Figure 20 comprises the flow chart of the embodiment of down link reception & disposal.
Figure 21 diagram has poll and time-division medium and accesses the embodiment of both TDF super frame structures.
Figure 22 diagram has the embodiment of the TDF super frame structure of blending agent access mechanism.
Figure 23 illustrates SP and the station in block diagram and the TDF network in TDF network.
Figure 24 illustrates the embodiment of poll notification routines.
Figure 25 illustrates the flow chart of poll routine.
Figure 26 diagram has the embodiment of the TDF super frame structure of blending agent access mechanism.
The flow chart of the processing of merotype when Figure 27 diagram is switched to from the pattern based on contention.
Figure 28 diagram from time merotype be switched to the flow chart of the processing of the pattern based on contention.
Figure 29 is the block diagram of TDF (ADoC) STA.
Figure 30 is according to the block diagram of the TDF with dual mode device (ADoC) STA of embodiment.
Figure 31 is the block diagram of the hardware implementation scheme of TDF (ADoC) STA dual mode device.
Figure 32 is the block diagram of another hardware implementation scheme of TDF (ADoC) STA dual mode device.
Figure 33 is the block diagram that the dual mode device of present principles is embodied as to the modulator-demodulator of Figure 10.
Figure 34 illustrates another embodiment of TDF super frame structure.
Embodiment
At least the discussion of Fig. 1-8 is presented and comprised one or more novelties and various embodiments creationary aspect or feature.At least one in these embodiments provides a kind of system that uses the characteristic feature of wireless system to transmit data on cable.Particularly, at least one embodiment is used time division multiplexing on coaxial cable.Such system for example allows cable television operators TV signal is provided in a part for frequency spectrum and provides Additional Services on another part of frequency spectrum.These Additional Services for example can comprise internet access, and it comprises for searching for internet and watching the access of the webpage on internet and for the access of (for example, such as,, video request program) of the service on receiving internet.
At least the discussion of Fig. 9-20 has been presented to additional embodiment, and at least one novelty encapsulating by description in these additional embodiments expanded the discussion to Fig. 1-8 with creationary use.A specific embodiment comprises the modulator-demodulator that receives Ethernet grouping from multiple main frames.Each main frame may be attempted to communicate by letter from different websites by router.Modulator-demodulator becomes these packet encapsulation according to the format structure (format structure) for wireless transmission or agreement and formatted single grouping.But the grouping sending after encapsulation on coaxial cable receives for router.In one embodiment, the different website that router sends to each main frame to attempt to communicate with it these groupings then.
Compared with only encapsulating the system of a grouping, the encapsulation that above-mentioned embodiment is used provides the increase of throughput at every turn.Thus, the expense (overhead) of distribution (spread out) wireless format structure in multiple Ethernet groupings.This uses contrary with the routine of encapsulation, it for example allows to provide supplementary features by another communication layers, or guarantees downward compatibility (backward compatibility) by retaining traditional (legacy) frame structure in the data after encapsulation.In addition, depend on system, the encapsulation of above-mentioned embodiment also allows by the data encapsulation from multiple sources together, and the data encapsulation that will go to different end users (for example, different websites, or different main frames) together.
At least the discussion of Figure 21-34 is presented to other embodiment.Some in these embodiments are devoted to the frame structure being associated with poll and the access based on contention and novelty and the creationary aspect being associated with poll and the access based on contention.Other embodiments are devoted to double mode configuration.
This application provides the description of Fig. 1-8 now.Note, the various piece of the description to Fig. 1-8 is used title.To the title of certain portions should not be interpreted as disclosing of this part to be restricted to the theme of this title, or also should not be interpreted as disclosing of other parts to be restricted to the theme except the theme of this title.Title is exemplary, and is intended to as general the assisting to reader.Title is not intended to retrain flow process of the present disclosure or limits application of the present disclosure or generality.
total description
application situation
In order to provide data, services by existing coaxial cable TV system (CATV), at least one embodiment has been disposed access point (AP) and the station (STA) of deferring to time-division function (TDF) agreement in cable access network.AP is connected via the splitter in hierarchical tree (splitter) with STA.In this way, user is in and can accesses remote I P core network via cable access network.As illustrated in figure 1, illustrate detailed network topology.
As seen from Figure 1, in this typical access network infrastructure, have the AP that defers to TDF agreement, this AP has an Ethernet interface being connected with IP core network and a coaxial cable interface being connected with cable access network.At the other end of cable access network, there is the STA that defers to TDF agreement, that is, terminal, described STA is connected with cable access network via coaxial cable interface and is connected with the LAN of family (local area network (LAN)) via Ethernet interface.
According at least one embodiment, according to 802.11 series of canonical, TDF AP and STA implementation agreement stack discretely in logical link control sublayer, media access control sublayer and physical layer.But in media access control sublayer, TDF AP and STA utilize TDF frame to transmit entity and replace 802.11 frames transmission entities.Like this, transmit entity for the media access control sublayer of TDF AP and STA by 802.11 frame encapsulation/decapsulation entities and TDF frame and form, and transmit entity by 802.11 frame encapsulation/decapsulation entities and 802.11 frames and form for deferring to the media access control sublayer of 802.11 AP and STA.For integrated AP and STA, TDF frame transmits entity and 802.11 frames and transmits entity and can and deposit simultaneously, with provide 802.11 and TDF function the two.Can realize two kinds of switchings between pattern by manual or dynamic-configuration.
basic skills
The main thought of TDF agreement is in coaxial cable medium instead of transmits IEEE802.11 frame aloft.The object of utilizing IEEE 802.11 mechanism is to utilize the ripe hardware and software embodiment of 802.11 protocol stacks.
The principal character of TDF be its uniqueness for transmitting the medium connection control method of IEEE 802.11 Frames., it does not utilize conventional IEEE 802.11DCF (distributed coordination function) or PCF (point coordination function) mechanism to exchange the mac frame that comprises MSDU (MAC service data unit) and MMPDU (Medium Access Control (MAC) Management Protocol Data Unit).But it transmits mac frame with time-division cut-in method.TDF is the cut-in method that has defined the detailed embodiment of the frame transmission entity that is arranged in media access control sublayer like this.
For comparison purposes, as shown in Figure 2, we illustrate the IEEE802.11MAC sublayer agreement in OSI Reference Model at this.And in Fig. 3, illustrate the definite position of TDF agreement in OSI Reference Model.
communication pattern entrance routine
Current, two kinds of communication patterns at the station of deferring to as described below TDF have been proposed.Pattern is IEEE 802.11 operator schemes for standard, and it observes the frame structure and the transfer mechanism that in IEEE 802.11 series standards, define; Another kind of pattern is TDF operator scheme, will the details about this TDF operator scheme be discussed in paragraph below.In Fig. 4, indicate and in the time that TDF STA starts, determined the strategy that enters which operator scheme.Once TDF STA receives synchronization frame from AP, make TDF STA can enter TDF pattern, if do not receive synchronization frame default in overtime, TDF STA remains unchanged or transfers IEEE 802.11 patterns to.
tDF protocol function is described
cut-in method
Physical layer in TDF station can have the ability of multiple data transfer rate, and it allows to carry out under the object of improving performance and plant maintenance the embodiment that dynamic rate switches.Current, TDF can support at station the data rate of three types: 54Mbps, 18Mbps and 6Mbps.Mainly under 54Mbps data rate, provide data, services.When for station, support 54Mbps data to transmit while there is some problem, can temporarily be switched to 18Mbps data rate.6Mbps data rate operator scheme is to design for the object of network operation and station debugging.
Can be before TDF station enters TDF Communications routines configuration data speed statically, and in during whole communication process, keep equivalent data rates.On the other hand, TDF station can also support the dynamic data rate of viability to switch.The criterion that data rate switches can be based on channel signal quality and other factors.
The basic cut-in method of TDF agreement is time-division multiplex access (TDMA), and it is by being that different time slots allows multiple users to share this channel by same channel distribution.TDF STA one after the other transmits uplink traffic one by one fast, and each TDF STA uses they self time slot in TDF super frame, that assigned by TDFAP.For downlink traffic, STA shared channel, and by the destination-address information in Frame or management frames and their address are compared to Frame or the management frames selected taking them as target.Fig. 5 illustrates in the time there is the individual STA that simultaneously competes the meeting of up link conveyer of m for the TDF super frame structure of typical TDF super frame and the example of time slot allocation.
As shown in Figure 5, there is the time slot of tdfTotalTimeSlotNumber fixed number in each TDF super frame, and it is by forming below: one for the synchronization slot from TDF AP to TDF STA tranmitting data register synchronizing information; One for sending contention (contention) time slot of the registration request that uplink time slot is distributed; TdfUplinkTimeSlotNumber the uplink time slot being used to TDF AP transmission data and some management frames one by one by the TDF STA registering; And transmit data and register tdfDownlinkTimeSlotNumber the downlink time slots that response management frame uses to modulator-demodulator by TDFAP.Except synchronization slot, all other time slots that are named as public time slot have length and equal the identical duration of tdfCommonTimeSlotDuration.The value of definition tdfCommonTimeSlotDuration is to allow, for peak data rate pattern, in a standard time slot, transmit at least one maximum IEEE 802.11PLCP (Physical layer convergence protocol) protocol Data Unit (PPDU).The duration tdfSyncTimeSlotDuration of synchronization slot is shorter than the duration of public time slot, and this is because the clock synchronous frame transmitting from TDF AP to TDF STA in synchronization slot is shorter than 802.11 Frames.
As a result, can calculate by following formula the duration of a TDF super frame that is defined as tdfSuperframeDuration:
tdfSuperframeDuration＝tdfSyncTimeSlotDuration+tdfCommonTimeSlotDuration*(tdfTotalTimeSlotNumber-1)
Relation between tdfTotalTimeSlotNumber, tdfUplinkTimeSlotNumber and tdfDownlinkTimeSlotNumber meets following equation:
tdfTotalTimeSlotNumber＝tdfUplinkTimeSlotNumber+tdfDownlinkTimeSlotNumber+2
The number of the uplink time slot distributing for TDF STA in TDF super frame in addition, can be changed into tdfUplinkTimeSlotThreshold from 1.Correspondingly, in TDF super frame, available downlink time slots can be changed into (tdfTotalTimeSlotNumber-2-tdfMaximumUplinkTimeSlotNumber) from (tdfTotalTimeSlotNumber-2).At every turn in the time that one of existence requires the TDF STA of uplink time slot, TDF AP will draw (deduce) one or more time slots from available downlink time slots, and then by these time slot allocation to TDF STA, as long as after this uplink time slot number be no more than tdfMaximumUplinkTimeSlotNumber.In different embodiments, the value of tdfMaximumUplinkTimeSlotNumber may change.But must careful selection to make at least to exist a downlink time slots to use for the TDF STA being associated, to ensure the QoS of data, services.In addition, can merge all time slots in succession that transmit for same direction, used by same TDF STA or AP to send continuously mac frame, thereby avoid the waste of locating at these time slot edges (edge) being caused by unnecessary conversion and guarantee (guarding).
In current embodiment, tdfCommonTimeSlotDuration is about 300us, it transmits at least one maximum 802.11PPDU for TDF STA in a public time slot of 54M pattern is enough, and each TDF super frame exists 62 time slots altogether.In these time slots, in this way, there are 20 uplink time slots and 40 downlink time slots.In the time there is 20 STA, can ensure that each TDF STA can use the downlink data rate of uplink data rate the shared 30Mbps (40 continuous time slots) of 680kbps; In the time there is 30 STA, can ensure that each TDF STA can use the downlink data rate of uplink data rate the shared 22.5Mbps (30 continuous time slots) of 680kbps.TdfMaximumUplinkTimeSlotTimeNumber is 30.Finally, be about 18.6ms as the value of the tdfSuperframeDuration of duration altogether of 61 public time slots and 1 synchronization slot, and for different purposes, can be defined as different values.For example, if only there is 1 TDFSTA, can ensure that it has 4 time slots to realize the downlink data rate of the uplink data rate of about 18Mbps and the 18Mbps (4 continuous time slots) of self.In this way, be about 4ms as the value of the tdfSuperframeDuration of duration altogether of 9 data slots and 1 synchronization slot.
the form of frame
In 802.11 specifications, there are three main frame types.Usage data frame is with from a station to another station swap data.Depend on network and can occur some different types of Frames.Execution area cleaning (area clear) operates, channel obtains and safeguards the function of (carrier-sensing maintenance) and the affirmative acknowledgement to received data with carrier detect to use control frame to come together together with Frame.Control frame is worked with from a station to another station delivering data reliably together with Frame.More specifically, a key character of data frames exchange is to have acknowledgement mechanism, and correspondingly exist for each down link unicast frame reply (ACK) frame, to reduce the possibility of the loss of data causing due to insecure wireless channel.Finally, management frames is carried out monitoring function: use management frames to add and to leave wireless network and move associated (association) from an access point to another access point.
But, in TDF system, because TDF STA waits for from the synchronization frame of TDF AP passively to find target TDF AP, therefore, there is not the demand to classical exploration (probe) claim frame and probe response frame.In addition, switching frame in coaxial cable instead of aloft, therefore, needn't define RTS and CTS frame and carry out cut-back region and prevent hiding node problems, and needn't define ACK frame and guarantee the reliability of delivering data frame.
Therefore,, in TDF agreement, we only use some useful 802.11MSDU and MMPDU type for the data that transmit by coaxial cable situation.For example, we utilize the data subtypes in data frame type, and it is used to encapsulation compared with the data on upper strata and will be sent to another station from a station compared with the data on upper strata.In addition,, in order to tackle the needs of clock synchronous in TDF system, we have defined the management frames-synchronization frame of new kind; And for realizing the function of uplink time slot request, distribution and release, we define the management frames of other four kinds, that is, and registration request, registration response, de-registration request and survival notice.
Generally, we have defined four kinds of new subtypes in management frame in TDF agreement.Following form definition the type that increases in TDF agreement and effective combination of subtype.Form 1 shows effective type and the subtype for the TDF frame that in TDF agreement, increase.
Form 1
Type specification Subtype specification
Management Synchronously
Management Registration request
Management Registration response
Management De-registration request
Management Survival notice
tDF accesses routine
TDF AP finds and clock synchronous routine
TDF agreement depends on the distribution (distribution) of timing information to all nodes to a great extent.First, TDF STA intercepts synchronization frame to determine whether to exist available TDF AP.Once TDF STA enters TDF Communications routines, carry out adaptive local timer with synchronization frame, TDF STA will determine whether taking turns to it based on this this locality timer and send uplink frame.At any time, in Synchronization routines, TDF AP is main frame and TDF STA is slave.Further, if TDF STA does not also receive any synchronization frame from the AP being associated within the predetermined threshold value period (it is defined as tdfSynchronizationCycle), it will think that this AP has exited service, and then it will stop TDF communication process and start to find any TDF AP by again intercepting synchronization frame.
In TDF system, all STA that are associated should be synchronized to common clock with same TDF AP.TDF AP should periodically transmit and be known as synchronous special frames with the modulator-demodulator in synchronous its local network, described in be known as the clock information that synchronous special frames comprises TDF AP.Each TDF STA should safeguard local timing synchronization function (TSF) timer, to guarantee that it synchronizes with the TDF AP being associated.After receiving synchronization frame, TDF STA should accept the timing information in frame all the time.Be different from the timestamp in received synchronization frame if receive the TSF timer of TDFSTA, receive TDF STA and should its local timer be set according to the value of received timestamp.Further, it can increase little biasing to received timing value and processes with explanation (account for) this locality of being undertaken by transceiver.
TDF AP should be to transmit at each TDF super frame time quantum and generates a synchronization frame and send this synchronization frame in the Sync of each TDF super frame time slot.
Registration routine
Whole registration routine has been described to Fig. 6 n-lustrative.Once TDF STA has obtained timer synchronizing information from synchronization frame, it will learn when start time slot 0.If TDF STA and any TDF AP are unconnected, it will be attempted to the specific TDF AP registration that sends synchronization frame by send registration request frame to TDF AP during contention slots, and described contention slots is the second time slot in TDF super frame.Should design modestly the duration of the contention slots that equals tdfCommonTimeSlotDuration and the structure of registration request frame, to allow sending at least tdfMaximumUplinkTimeSlotNumber registration request frame in a contention slots.Based on this design, contention slots is divided into the sub-slots of tdfMaximumUplinkTimeSlotNumber equal length.
As long as TDF STA finds target TDF AP, it will be according to following methods, selects a sub-slots to send registration request frame to TDF AP in contention slots:
A. at every turn in the time that TDF STA is assigned with uplink time slot, storage is defined as uplink time slot number tdfAllocatedUplinkTimeSlot, that distribute (number) by it, and it indicates the position of this time slot in whole uplink time slot pond (pool) and its scope from 1 to tdfMaximumUplinkTimeSlotNumber.
B. in the time that TDF STA requires uplink time slot at every turn, TDF AP should try one's best to distribute identical uplink time slot to identical TDF STA.
C. in the time determining to select which sub-slots to send registration request frame, if there is the tdfAllocatedUplinkTimeSlot value of storage, TDF STA bundle timeslot number is set to identical with tdfAllocatedUplinkTimeSlot; If there is no such value, TDF STA will select randomly a sub-slots in tdfMaximumUplinkTimeSlotNumber available sub-slots.TDF STA will send registration request frame to TDF AP in the random sub-slots of selecting.
The object of this operation is to reduce the chance of conflict in the time that many STA start simultaneously and attempt to same TDFAP registration simultaneously.
In registration request frame, TDF STA will be listed in all data rates and carrying some useful information such as the carrier wave/noise ratio of received signal that it is supported at that time.It can be from the highest data rate, utilizes the different data rate of supporting to send some registration request frame in succession.After sending frame, TDF STA is by the registration response frame of intercepting from TDF AP.
After TDF STA receives registration request frame, based on following methods, TDF AP will return to different types of registration response frame to TDF STA in downlink time slots:
If the uplink time slot A. having distributed equals tdfMaximumUplinkTimeSlotNumber, TDF AP will put into uplinkTimeSlotUnavailable designator in frame main body.
If B. TDF AP is not supported in any data rate listed in the supportedDataratesSet in registration request management frames, TDF AP will put into unsupportedDatarates designator in frame main body.
Can be used for if C. existed the public data rate that the uplink time slot that distributes and TDF AP and TDF STA all can support, AP will distribute a uplink time slot and select suitable public data rate according to some information such as carrier wave/noise ratio in the registration request frame of STA, and then sends registration response frame to TDF STA.In frame main body, by the information comprising about distributed uplink time slot and selected data rate.
After successfully registering routine, TDF STA and TDF AP will be to using which uplink time slot and data rate to reach an agreement.
Segmentation (fragmentation)/solution segmentation routine
In TDF agreement, the time slot duration that MSDU is transmitted is fixed as tdfCommonTimeSlotDuration.In some data rate, in the time that the length of MSDU is greater than threshold value, can not in single time slot, transmit.So, when for up link transmit data frame length in be defined as tdfFragmentationThreshold and depend on different pieces of information speed and change threshold value time, scheduling this Frame with before transmitting it, should carry out segmentation to it.For all segmentations except last segmentation, the length of fragmented frame should be the eight bit byte (Octets) (tdfFragmentationThreshold eight bit byte) of equal number, and last segmentation can be less.After segmentation, the frame after segmentation should be put into and wait to send out (outgoing) queue, to be sent to TDF AP.Can in TDF frame transmission entity, move this segmentation routine or transmit at TDF frame the tdfFragmentationThreshold dynamically arranging in entity by use and in compared with upper strata, move this segmentation routine.
At TDF AP end, the each fragmented packets receiving is containing the information that allows to re-assembly (reassemble) whole frame from the composition segmentation of frame.The head of each segmentation comprises TDF AP and re-assemblies the following information that frame uses:
A. frame type (Frame type)
The address (Address of the sender) of the transmit leg that B. (Address 2) field obtains from address 2
C. destination-address (Destination address)
D.Sequence Control (sequence control) field: this field allows TDF AP to check allly to enter segmentation and all belong to the sequence that same MSDU and described segmentation should be reassembled into.Serial number in SequenceControl field keeps identical to all segmentations of MSDU, and segment number in Sequence Control field is to each segment increasing.
E.More Fragments (more segmentations) designator: indicating this to TDF AP is not the last segmentation of Frame.Only have last or unique (sole) segmentation of MSDU to be set to zero by this bit.All other segmentations of MSDU should be set to one by this bit.
TDF AP should be by carrying out reconstruct MSDU according to the sequential combination segmentation of the segment number son field of Sequence Control field.Be set to zero segmentation if also do not receive More Fragments bit, TDF AP will know that frame is also imperfect.TDF AP mono-receives More Fragments bit and is set to zero segmentation, and it is just known for this frame and may not receive more segmentation.
TDF AP should be each frame receiving and safeguards reception timer.Also have tdfMaxReceiveLifetime attribute, it specifies the maximum time amount that a frame allows that receives.In the time receiving first segmentation of MSDU, start and receive timer.If received frame timer exceedes tdfMaxReceiveLifetime, TDF AP abandons the segmentation of all receptions of this MSDU.If receive the additional segmentation of this MSDU after the tdfMaxReceiveLifetime that exceedes (directed) MDSU being managed, should abandon these segmentations.
Up link transmits routine
After TDF AP receives registration response frame, TDF STA by analysis frame main body to check whether it has been given uplink time slot.If be not given uplink time slot, it will stop applying for uplink time slot for a moment and subsequently.If be given uplink time slot, it will use the data rate of indicating in registration response frame during assigned time slot, to start to transmit uplink traffic.
Start up link transmission during assigned time slot time, if exist at least one to wait to send out a frame in the outgoing queue of TDF STA, TDF STA will send the first frame in its outgoing queue to TDF AP.After this, TDF STA sends the second uplink frame by the length and the assessment possibility that check the second uplink frame in the residue duration of assigned time slot.If can not, it sends the second uplink frame in stopping up link transmission routine and waiting for during next TDF super frame in the time slot of assigning.If of course, it will send the second frame to destination TDF AP immediately.Send routine and will continue in this way operation, until the time slot of assigning finishes or do not have any uplink frame that will transmit.
Down link transmits routine
In whole TDF Communications routines, total downlink time slots number may dynamically change due to the STA number being associated changing.In the time that TDF AP prepares to send frame to the STA that is associated, it by the time remaining in remaining downlink time slots with compare for using decided through consultation (agreed) data rate to transmit the required duration of specific descending chain circuit frame.Then based on this result, whether it should transmit this frame with specific data rate by decision during this TDF super frame.In addition, TDFAP does not need any descending chain circuit frame to carry out segmentation.
When not being while sending the time of uplink traffic for the STA being associated, STA will always intercept channel to find the possible descending chain circuit frame taking it as target.
Nullify routine
As shown in Figure 7, if TDF STA determines to exit TDF Communications routines, the introversive TDF AP being associated during line link time slot is thereon sent de-registration request frame by it, so that notice TDF AP is released to the uplink time slot resource that its distributes.After receiving de-registration request frame, TDF AP is by the uplink time slot vacant (free) that makes to assign for this TDF STA and put it into vacant time slot pond in the future.
Survival notification routines
Referring now to Fig. 8, for releasing resource as quickly as possible in the time that TDF STA collapses suddenly or closes, TDF STA must report its viability by periodically sending survival notification frame to TDF AP in during line link time slot period thereon.If there is not any survival notice within the predetermined threshold value period that is named as tdfAliveNotificationCycle, the TDF AP being associated will think that TDF STA has exited service, and be then released to the uplink time slot that this TDF STA distributes, just as received de-registration request frame from this TDF STA.
In order to ensure have many rate capacities TDF STA's and deposit and interoperability, this normalized definition one group of rule all should following of all stations:
A. should transmit synchronization frame with the minimum speed limit in the set of TDF basic rate, these synchronization frames can be understood by all STA.
B. should on the data rate of supporting of selecting by login mechanism, send all frames with destination unicast address.Do not stand the speed of not supporting with receiving station is transmitted to unicast frame.
C. should transmit all frames with destination multicast address with the flank speed in the set of TDF basic rate.
It is below the description of Fig. 9-20.At least the embodiment of the one or more systems that for example can describe for Fig. 1-8 has been described in Fig. 9-20.Certainly, the feature of the embodiment of Fig. 9-20 and aspect can be for other systems.
As mentioned above, TDF agreement can be replaced conventional 802.11DCF (distributed coordination function) or PCF (point coordination function) mechanism.Such system can be utilized WLAN (802.11) network of widespread deployment and may become the advantage of more and more ripe and cheap WLAN chipset.This system provides the solution of cost-effective for the two-way communication of catv network by transmit WLAN signal in cable system, even if in environment aloft instead of carry out transmission/reception and created WLAN agreement in cable system.In this system, the basic cut-in method of TDF agreement is TDMA, and it is by being that different time-gap allows multiple users to share this same channel by same channel distribution.The time slot that each TDF station is used this TDF station self of assigning in TDF super frame, by TDF AP (access point), one after the other transmits uplink traffic one by one fast.For downlink traffic, these station shared channels (for example, as shown in the TDF super frame at Fig. 5), and by the destination-address information in these frames and their address are compared to select the frame taking them as target.
With reference to Fig. 9, show typical TDF network 900.Network 900 provides from the connection of subscriber household 910 and 920 (or other resource or network) 930 to internet.Subscriber household 910 and 920 is communicated with access point (AP) 940 by cable system 950.AP 940 can be positioned at for example adjacent place of family 910 and 920, or is positioned in the apratment building thing that comprises family (apartment in this case) 910 and 920.For example, can have AP 940 by cable operator.AP 940 is further coupled to router 960 by ethernet network 970.Router 960 is also coupled to internet 930.
As should be clearly, term " coupling " refer to direct connection (there is no intermediary's assembly or unit) be indirectly connected (one or more intermediaries assembly and/or unit) both.Such connection can be for example wired or wireless, and permanent or temporary transient.
Subscriber household 910 and 920 can have various configuration, and each family can be differently configured.But, as shown at network 900, subscriber household 910 and 920 each stations (being known as modulator-demodulator) 912 and 922 that comprise respectively.Modulator-demodulator 912,922 is coupled to the first main frame (main frame 1) 914,924 and the second main frame (main frame 2) 916,926 by Ethernet 918,928 respectively.Each main frame 914,916,924 and 926 can be for example computer or other treatment facility or communication equipment.
Exist network 900 can allow multiple main frames (for example, 914,916,924 and 926) to be connected to the whole bag of tricks of router 960.Four kinds of embodiments are below discussed, for simply, are only considered modulator-demodulator 912 and main frame 914 and 916.
In the first method, modulator-demodulator 912 serves as another router.Identify main frame 914 and 916 by the IP address of main frame 914 and 916, and modulator-demodulator 912 by the IP Packet routing from main frame 914 and 916 to router 960.The method 1 typically needs modulator-demodulator 912 to move router software, and this needs extra memory and the disposal ability of increase.
In the second method, modulator-demodulator 912 serves as bridger (bridge).Modulator-demodulator 912 and AP 940 use wireless distribution system (WDS) mechanism of standard to carry out transfer layer 2 to divide into groups to router 960.Main frame 914 and 916 is identified by its medium access control (MAC) address.The method 2 is parts of 802.11 standards and can serves multiple main frames simultaneously.But not every AP and modulator-demodulator are all supported WDS, and those support AP and the modulator-demodulator of WDS often only to possess limited support.For example, for some AP and modulator-demodulator, you can not use Wi-Fi protection access (WPA) together with WDS, and this may introduce safety issue.
In third method, modulator-demodulator 912 uses MAC camouflage (masquerade) source MAC (source is one of main frame 914 and 916) of Ethernet grouping to be changed into the MAC Address of himself.Therefore from the angle of router 960, router 960 is only seen modulator-demodulator 912.Utilize the method, modulator-demodulator 912 once only can be served a main frame.
In other method, modulator-demodulator 912 uses the following encapsulation describing in further detail.Each in above method has merits and demerits, and these merits and demerits may depend on embodiment and change.But, method for packing provides specific advantage, these specific advantages are that this method for packing is not conventionally by needing modulator-demodulator operation router software to allow modulator-demodulator simpler, and it does not typically introduce safety issue, and can once serve multiple main frames.
In addition, this method for packing, by using single WLAN grouping to transmit each grouping from main frame, has been avoided the large expense being associated with first three methods.Thereby first three methods causes the expense of the WLAN grouping of the each grouping for shifting from main frame, and has reduced accordingly throughput.In TDF environment, typically increase the weight of this poor efficiency.In TDF environment, the duration of time slot is fixed, and time slot is designed in a time slot, only allow to transmit a WLAN grouping.Thereby, in each time slot, only can transmit a host packet.
Correspondingly, this method for packing provides one or more in various advantages conventionally.For example, such advantage comprises: the fail safe of simpler router design and operation, increase, serve multiple main frames, and the efficiency and the throughput that increase.
In a word, at least one embodiment of this method for packing comprises that by multiple Ethernet packet encapsulation be a WLAN grouping.This WLAN divides into groups equally large the maximum length allowing with TDF time slot.AP (for example, another modulator-demodulator) is descapsulated into WLAN grouping each Ethernet grouping and they is sent to router.For the communication in opposite direction, modulator-demodulator sends to (multiple) main frame by decapsulation WLAN grouping and by each Ethernet grouping.
With reference to Figure 10, legend 1000 comprises multiple modulator-demodulators (wherein two are illustrated clearly) and AP.This legend comprises modulator-demodulator #1 1010, modulator-demodulator #N 1020 and AP 1030, and each in modulator-demodulator 1010 and 1020 is coupled to AP 1030 by cable system 1040.Another embodiment is used the cable system separating for each modulator-demodulator.
Modulator-demodulator 1010 and 1020 and AP 1030 comprise the functional unit of same names, although some outsidely connects difference and assembly itself is carried out different functions for modulator-demodulator and AP.Thereby, provide public unit to be used as modulator-demodulator and AP.But should know can be for modulator-demodulator and AP design different unit, those required functions of modulator-demodulator or AP are only carried out respectively in this different unit.
Modulator-demodulator 1010 comprises: local application layer 1011, tcp/ip layer 1012 afterwards, bridger 1014 afterwards.Bridger 1014 is coupled to Ethernet interface 1015, packet aggregation/disaggregation module (PADM) 1016 and WLAN interface 1017.PADM 1016 is also coupled to WLAN interface 1017.Ethernet interface 1015 is coupled to ethernet network 1052, and ethernet network 1052 is coupled to the first main frame (main frame 1) 1054 and the second main frame (main frame 2) 1056.
Modulator-demodulator 1020 is similar to modulator-demodulator 1010.But modulator-demodulator 1020 is coupled to ethernet network 1062, ethernet network 1062 is coupled to the first main frame (main frame 1) 1064 and the second main frame (main frame 2) 1066.The assembly of modulator-demodulator 1020 is shown identical with the assembly of modulator-demodulator 1010.But, should be clear, setting up modulator-demodulator 1010 and 1020 and during in modulator-demodulator 1010 and 1020 operation, for example various configuration parameters are by difference.
AP 1030 comprises: local application layer 1071, tcp/ip layer 1072 afterwards, bridger 1074 afterwards.Bridger 1074 is coupled to Ethernet interface 1077, PADM 1076 and WLAN interface 1075.PADM 1076 is also coupled to WLAN interface 1075.Ethernet interface 1077 is coupled to ethernet network 1082, and ethernet network 1082 is coupled to router one 090 then.WLAN interface 1017 and 1075 is communicated with one another and is coupled by cable system 1040.
Router one 090 is further coupled to internet 1095.Thereby, between main frame 1054,1056,1064,1066 and internet 1095, exist and connect.
Various local application layers (1011,1071) are the index beds for moving local application and connecting with other layer of framework.Various tcp/ip layers (1012,1072) are for moving TCP/IP and the index bed of the service (comprise with other layer of framework and connecting) being provided by such layer being provided typically.Various Ethernet interfaces (1015,1077) are the standard cells for being attached to ethernet network or connecting from ethernet network.Such interface 1015,1077 transmits and receives Ethernet grouping and operates according to Ethernet protocol.
Various WLAN interfaces (1017,1075) are the unit for being attached to wlan network or connecting from wlan network.Such interface 1017,1075 transmits and receives WLAN grouping and according to WLAN protocol operation.But in legend 1000, WLAN interface 1017,1075 is actual to be coupled to cable system 1040 instead of to use radio communication.
Can implement Ethernet and WLAN interface 1015,1017,1075 and 1077 with for example hardware such as the insertion card for computer (plug-in card).Can also most of implement this interface with software, this software is such as using the instruction of being implemented by treatment facility to carry out the program of the function of executive's interface.Such interface for example will generally include, for (receiving actual signal, connector) and for example, for (cushioning received signal, transmission/reception buffer) part, and typically comprise the part (for example, signal processing chip is whole or a part of) for the treatment of signal.
Various bridgers (1014,1074) are the unit that forwards grouping between Ethernet interface and WLAN interface.Can be with software or hardware implementation bridger, or bridger can be only logic entity.Comprise treatment facility (such as integrated circuit) or one group of instruction in the upper operation for the treatment of facility (such as the processor of operation bridger software) for the embodiment of the standard of bridger.
PADM 1016 and 1076 carries out various functions, comprises the packet encapsulation and the decapsulation that are described further below.Can combine to implement PADM 1016 and 1076 with software for example, hardware, firmware or certain.Implement software scheme comprises for example one group of instruction such as the program of moving on treatment facility.Hardware implementation scheme comprises for example special chip such as application-specific integrated circuit (ASIC).
With reference to Figure 11, process 1100 and described processing from main frame to modulator-demodulator that shift grouping from.Further transmit this grouping from modulator-demodulator and receive for AP, and for being finally delivered to router also then to final destination.This processing 1100 is also called uplink transmission process.
Process 1100 and comprise that use is for example connected to AP (1110) in the previous processing of describing of the application by modulator-demodulator.Such processing can comprise for example comprising to be verified and operation associated standard WLAN agreement.
Then, process 1100 and comprise: one or more main frames send one or more groupings (1120) to modulator-demodulator, and modulator-demodulator receives (multiple) groupings (1130) that send.Attention: send grouping and receive for router, this router is by extremely final (multiple) destination of (multiple) delivery of packets.In the embodiment of Figure 10, modulator-demodulator 1010 is through Ethernet interface 1015 grouping that the one or more middle reception from main frame 1054 and 1056 sends by ethernet network 1052.
Then modulator-demodulator is determined by WLAN interface and will be sent (multiple) groupings (1140).Modulator-demodulator is made this by identification through WLAN interface couple in router (as contrary, by identifying through another interface couple in router (not shown)) and is determined (1140).In the embodiment of Figure 10, modulator-demodulator 1010 sends received (multiple) grouping to bridger 1014, and bridger 1014 is made these definite (1140).
Then, modulator-demodulator comprises multiple groupings (1150) of one or more received groupings for router encapsulation.Encapsulation (1150) can comprise from multiple main frames, the grouping that for example main frame 1054 and 1056 from the embodiment of Figure 10 receives.In addition, encapsulation can be included in (multiple) grouping receiving in operation 1130 and previously receive and be stored in the grouping in queue.
In the embodiment multiple groupings not being encapsulated, this embodiment can, by separately each Ethernet grouping being encapsulated, be used bridger that Ethernet packet map is divided into groups to each WLAN.This encapsulation for example can comprise the data division using whole Ethernet groupings as WLAN grouping and add additional WLAN head.
In addition the embodiment multiple groupings not being encapsulated, does not even need each Ethernet grouping to encapsulate.And such embodiment for example can be by utilizing WLAN head to replace Ethernet head and by adding alternatively one or more added field, each Ethernet grouping being transformed to each WLAN grouping.
For example, with reference to Figure 12, show the conversion 1200 that receives the Ethernet grouping 1210 that comprises Ethernet head 1220 and data division 1230.Conversion 1200 produces the WLAN grouping 1240 that comprises WLAN head 1250, data division 1230 and Frame Check Sequence (FCS) 1260.
But implementation and operation 1150 comprises that by multiple Ethernet packet encapsulation be single WLAN grouping.In Figure 13, illustrate an embodiment of operation 1150.
With reference to Figure 13, conversion 1300 receives the multiple Ethernet groupings that comprise Ethernet grouping 1310,1312 and 1314, and produces single WLAN grouping 1318.Each in Ethernet grouping 1310,1312 and 1314 comprises respectively Ethernet head 1320,1322 and 1324, and comprises respectively data division 1326,1328 and 1329.
Ethernet grouping 1310,1312 and 1314 can be derived from same main frame, or different main frames.In addition,, although be to encapsulate Ethernet grouping 1310,1312 and 1314 for being sent to router, the final destination of Ethernet grouping 1310,1312 and 1314 can be different.For example, Ethernet grouping 1310,1312 and each in 1314 can be gone to the communicate by letter with it different internet site of (or attempting to communicate by letter) of one or more main frames.
Conversion 1300 is shown as including two intermediary operations.But other embodiment is not carried out any intermediary operation, and also have other embodiment to carry out more intermediary operation.
The first intermediary operation is transformed to Ethernet grouping the Ethernet grouping of expansion.Ethernet grouping 1310,1312 and 1314 is transformed to respectively the Ethernet grouping 1330,1332 and 1334 of expansion.In conversion 1300, all Ethernet grouping 1310,1312 and 1314 is included as respectively the data division 1336,1338 and 1340 of the Ethernet grouping 1330,1332 and 1334 of expansion.The Ethernet grouping 1330,1332 and 1334 of expansion also comprises respectively optional head 1342,1343 and 1344, and optional tail tag (tail) 1346,1347 and 1348.Head 1342,1343 and 1344 and tail tag 1346,1347 and 1348 can comprise various message segment, no matter whether typical these message segments are for head/tail tag, such as, for example, packet numbers (packets numbers), reply and retransfer information, source and/or destination-address and error checking information.
The second intermediary operation comprises that the Ethernet grouping of expansion is transformed to single " Ethernet in WLAN " (Ethernet-in-WLAN (EIW)) divides into groups 1350.EIW grouping 1350 comprises each the data division in the Ethernet grouping of expansion.Show two kinds of possible conversion.Solid arrow 1370 illustrates conversion and the dotted arrow 1375 that the first is possible and illustrates the possible conversion of the second.
As convert as shown in the solid arrow 1370 in 1300, data division 1352,1353 and 1354 corresponds respectively to the Ethernet grouping 1330,1332 and 1334 of the expansion being included.EIW grouping 1350 further comprises optional head 1356 (being also known as EIW head) and optional tail tag 1358, any information that it is described for head/tail tag before for example can comprising.
If do not have head or tail tag to be inserted into the Ethernet grouping of expansion, the data division (for example, data division 1336) of the Ethernet of expansion grouping becomes the data division (for example, data division 1352) of EIW grouping.In addition,, even if head or tail tag are inserted into the Ethernet grouping of expansion, embodiment also may abandon/ignore head or tail tag in the time forming EIW grouping.Under any situation in these cases, the data division of the Ethernet grouping of expansion and the data division of EIW grouping have identical data.
As convert as shown in the dotted arrow 1375 in 1300, data division 1352,1353 and 1354 needn't correspond respectively to the Ethernet grouping 1330,1332 and 1334 of expansion.That is to say, the data division of EIW grouping needn't comprise the Ethernet grouping of whole expansions.As dotted arrow 1375 is indicated, the Ethernet grouping of expansion can be divided into the data division of two EIW groupings.
More specifically, the illustrated embodiment of dotted arrow 1375 shows: the Part II of the Ethernet grouping 1330 of expansion is put into the data division 1352 of EIW grouping 1350 by (1), (2) the Ethernet grouping of all expansions 1332 is put into the data division 1353 of EIW grouping 1350, and the Part I of the Ethernet grouping 1334 of expansion is put into the data division 1354 of EIW grouping 1350 by (3).Thereby, under a kind of situation about EIW grouping 1350, the Ethernet grouping of the expansion that (1) first data division 1352 comprises part, and the Ethernet grouping of (2) last data division 1354 expansion of comprising part, the Ethernet that (3) intermediate data part (1353 and clearly do not illustrated any other data division) comprises complete expansion simultaneously divides into groups.Although not shown, but should be clear, in the data division of the EIW grouping before the Part I of the Ethernet grouping 1330 of expansion can being placed on, and (2) can be placed on the Part II of the Ethernet grouping 1334 of expansion in the data division of EIW grouping subsequently.
In the terminal stage of conversion 1300, EIW grouping 1350 is included as the data division 1360 in WLAN grouping 1318.WLAN grouping 1318 also comprises WLAN MAC head 1362 and FCS1364.
As should be clearly, not every embodiment be all used all optional heads and tail tag, does not even also use all (or any) optional intermediary operation (being also known as the stage).For example, other embodiment only copies a part for the Ethernet grouping of expansion to EIW grouping, for example, to more initial data (, data division 1326,1328 and 1329) is packed into the time slot of fixing duration.As should be clearly, based on design object and restriction, for each embodiment, to using which head and tail tag and comprising that the definite of how many intermediary operations can change.
With reference to Figure 14, Figure 140 0 shows PADM and how to encapsulate the embodiment that Ethernet divides into groups.PADM maintenance enters (ingress) queue, and each Ethernet grouping entering is placed on this and enters in queue.PADM is string 1420 by Ethernet packet concatenation (concatenate), and adds EIW head 1430 and WLAN head 1440.Depend on the information comprising in head 1430 and 1440, can build in advance these heads 1430 and 1440 or build these heads 1430 and 1440 after cascade Ethernet grouping.For example, at least one embodiment is included in the numeral (number) that represents the number (number) of Ethernet grouping in string 1420 in EIW head 1430.Suppose that Ethernet grouping can have variable length, go here and there after 1420 until Ethernet grouping has been assembled as, typically, this numeral is only available.As should be clearly, can define the needs that head 1430 and 1440 adapts to particular.
With reference to Figure 15, show the form 1500 of an embodiment of EIW head.Form 1500 comprises for serial number and replys the field 1510 of number, total grouping number 1520 and a series of packet descriptor, and this series of packets descriptor comprises a descriptor for each Ethernet grouping of encapsulation in WLAN grouping.Correspondingly, as indicated in the ellipsis of Figure 15, predict the packet descriptor of variable number.Show packet descriptor 1530 and 1540, each in packet descriptor 1530 and 1540 comprises grouping mark (being respectively 1550 and 1555) and block length (being respectively 1560 and 1565).
Serial number (1510) provides the sequence identifier of the data of encapsulation, and it allows recipient to reply the reception transmitting.Reply number the replying of data receiving is before provided.Total grouping number is the number of the Ethernet grouping of encapsulation in WLAN grouping.
Grouping mark (1550,1555) indicates whether the Ethernet grouping being associated is complete grouping.Suppose that time slot has the fixing duration, likely all Ethernet grouping may not pack given WLAN grouping into.Correspondingly, in specific embodiment, be desirably in any given WLAN grouping first and last Ethernet grouping will be typically incomplete.Block length (1560,1565) is indicated the length of specific Ethernet grouping.
Continue to process 1100, in the embodiment of Figure 10, for example, can carry out executable operations 1150 by the PADM of modulator-demodulator 1,010 1016.Executable operations 1150 in the assembly that other embodiment can be on bridger for example, Ethernet interface, WLAN interface, another intermediate module, bridger except PADM or the combination of assembly.As should be clearly, can combine to implement (multiple) assembly for executable operations 1150 with for example software (such as the program of instruction), hardware (such as IC), firmware (such as the firmware embedding) or its in processing apparatus.
In addition, PADM can be positioned at modulator-demodulator diverse location (such as, for example,, on bridger or between Ethernet interface and bridger), be positioned at one of each interface or bridger, and/or be distributed in multiple inter-modules.
Process 1100 and further comprise that modulator-demodulator sends the grouping (1160) after encapsulation by cable to AP.The grouping sending is intended to receive for router.Cable can comprise, for example, and coaxial cable, fiber optic cables or other wired transmission medium.
In specific embodiment, in the time that the uplink time slot of modulator-demodulator arrives, modulator-demodulator will be collected grouping and they be put into a large WLAN grouping from enter queue.This WLAN grouping is not more than the largest packet that time slot allows.On the contrary, in the time that time slot arrives, if WLAN grouping is large not to fill the duration of fixing time slot, an embodiment still sends this (less) WLAN grouping, and another embodiment sends empty (NULL) data.
With reference to Figure 16, process 1600 and described the processing that grouping, decapsulation grouping and delivery group for receiving after encapsulation become to divide into groups.This processing 1600 is also known as up link reception & disposal.
Process 1600 and comprise that AP passes through the grouping (1620) of WLAN interface from modulator-demodulator receives encapsulation.In the embodiment of Figure 10, the grouping that AP 1030 receives encapsulation from modulator-demodulator 1010.Receive this grouping by cable system 1040 (such as coax network) at WLAN interface 1075 places.
AP carries out decapsulation to extract the composition grouping (1630) that forms the grouping after encapsulation to received grouping.In the embodiment of Figure 10, WLAN interface 1075 sends received (after encapsulation) grouping to PADM 1076.PADM 1076 carries out decapsulation and provides the grouping of composition Ethernet to bridger 1074.For example, by (checking for example total grouping number 1520 and each packet descriptor, packet descriptor 1530) grouping mark (for example, grouping mark 1550) and block length (for example, block length 1560) carry out decapsulation.By checking such data, PADM 1076 can determine where each in composition grouping starts and finish.
Particularly, PADM 1076 checks that each composition divides into groups to guarantee that this composition grouping is complete Ethernet grouping.If the grouping of composition Ethernet is imperfect, PADM 1076 these incomplete groupings of reservation and wait are until receive the remainder (in general grouping after encapsulation subsequently) of this Ethernet grouping.In the time receiving the remainder of Ethernet grouping, PADM 1076 assemble complete Ethernet grouping and by complete Ethernet forwarding of packets to bridger 1074.
With reference to Figure 17, in Figure 170 0, describe the above embodiment for the operation 1630 of the grouping 1710 after received encapsulation.For simplicity, suppose that the grouping 1710 after received encapsulation is identical with the grouping transmitting of describing with reference to Figure 14.However, it should be understood that the variation between the grouping that may occur transmitted grouping in practice and receive.The grouping 1710 receiving comprises the string 1420 of WLAN head 1440, EIW head 1430 and the grouping of composition Ethernet.
In the time that PADM 1076 processes received grouping 1710, if the grouping of composition Ethernet is complete, this grouping (for example, grouping 1720) is offered to bridger 1074.If composition Ethernet grouping is imperfect, by this incomplete packet memory in waiting list 1730 (it needn't be arranged in PADM1076) until the remainder of this grouping arrive.Figure 170 0 illustrates that incomplete grouping 1740 is stored in waiting list 1730.For example, if (span) two WLAN groupings are crossed in Ethernet grouping, this may occur.In the time of packet integrity, this grouping is sent to bridger 1074.Note, WLAN grouping for example can comprise, the Ethernet grouping of a complete Ethernet grouping and a part.
With reference to Figure 18, process 1130 for further describing decapsulation, describe the PADM 1750 of the embodiment that PADM 1016 or 1076 is provided.PADM 1750 comprises wrapper 1760 and decapsulator 1770.Wrapper 1760 and decapsulator 1770 are communicatively coupled to bridger and WLAN interface.Provided the assembly of PADM 1750, more specifically, PADM 1750 can be known as packet encapsulation/decapsulation module.
In operation, as mentioned above, wrapper 1760 is accepted Ethernet grouping and the grouping of encapsulation Ethernet from bridger.Then the data after encapsulation are provided for WLAN interface.
In operation, the data of decapsulator 1770 from WLAN interface receives encapsulation.As mentioned above, received data are carried out decapsulation by decapsulator 1770, and provide data after decapsulation to bridger.
Very clear, other embodiment is possible and is foreseeable.For example, another embodiment has combined wrapper and decapsulator.And another embodiment is used the Virtual Ethernet feature of Linux.
Note, other embodiment of AP or modulator-demodulator directly sends the grouping encapsulation to bridger from WLAN interface.Bridger determines that this grouping is packed and this grouping is sent to PADM.
Continuing to process 1600, AP determines and composition grouping will be sent to router (1640).Can, at the difference place that processes 1600, this operation (1640) be carried out together with other many operations.In the embodiment of Figure 10, bridger 1074 is determined will be sent to grouping router one 090.
Then AP sends composition grouping (1650) by Ethernet interface to router.In the embodiment of Figure 10, bridger 1074 sends composition grouping to Ethernet interface 1077, and Ethernet interface 1077 sends described grouping by ethernet network 1082 to router one 090.
Router receives (1060) and processes (1070) described grouping.Processing for example can comprise a part that sends grouping or grouping to the further destination the website of communicating by letter with it such as main frame or attempt to communicate by letter with it.In addition, the grouping after encapsulation comprises that in the embodiment from the Ethernet grouping of multiple main frames, router can send bottom (underlying) information to multiple websites.
With reference to Figure 19, process 1800 processing of having described for receive the grouping of AP from router.Encapsulating packets, and transmit the grouping encapsulating from AP.Grouping after the encapsulation transmitting is intended to receive for modulator-demodulator, and composition grouping is intended to carry out last sending from modulator-demodulator to one or more main frames.This processing 1800 is also known as down link and transmits processing.
Processing 1800 comprises: router receives the one or more groupings (1820) that are intended to go to one or more main frames, and router sends (multiple) groupings (1830) that receive to AP.Router can be from for example just attempting to receive grouping with one or more websites of one or more main-machine communications.In the embodiment of Figure 10, router one 090 receives grouping from internet 1095.Then router one 090 sends received grouping by ethernet network 1082 to the Ethernet interface 1077 of AP 1030.
AP determines that the grouping that at least one will be received by WLAN interface is sent to modulator-demodulator (1840).In the embodiment of Figure 10, received grouping (it is Ethernet grouping) is routed to bridger 1074 by Ethernet interface 1077.Bridger 1074 is determined and will grouping be sent to for example modulator-demodulator 1010 by WLAN interface 1075.
AP will be sent to multiple groupings modulator-demodulator, that comprise one or more received groupings and encapsulate (1850).Note, multiple groupings all receive from router, but can be that at router place, from one or more different sources, (for example, different website) receives.In addition, encapsulation can be included in (multiple) grouping of receiving in operation 1820 and previous that receive and be stored in the grouping in queue.
About operation 1850, in the embodiment of Figure 10, bridger 1074 by received (multiple) forwarding of packets to PADM 1076.PADM 1076 is intended to received (multiple) grouping and (for example) to go to together with other grouping of modulator-demodulator 1010 and ranks, and the WLAN being formed for after the encapsulation of the downlink time slots that modulator-demodulator 1010 can use divides into groups.PADM 1076 maintains independent queue to each modulator-demodulator (being also known as station), comprises for the first queue of modulator-demodulator 1010 with for the second queue of modulator-demodulator 1020.As described before encapsulation in the time describing PADM1016 in conjunction with Figure 11-15.
AP is connected to modulator-demodulator and is sent the grouping after encapsulation by cable, is intended to carry out last sending (1860) to one or more main frames.In the embodiment of Figure 10, PADM 1076 in (round-bin) mode of circulation each in modulator-demodulator 1010 and 1020 prepare WLAN grouping.Then PADM 1076 supplies ready WLAN to WLAN interface 1075 and divides into groups to be inserted in TDF super frame structure in corresponding downlink time slots.Then WLAN interface 1075 uses TDF super frame structure to transmit the grouping after WLAN encapsulation to modulator-demodulator 1010 and 1020.
With reference to Figure 20, process 1900 and described for receiving grouping, the decapsulation grouping after encapsulation, and delivery group becomes the processing of grouping.This processing 1900 is also known as down link reception & disposal.
Processing 1900 comprises: modulator-demodulator is the grouping (1920) from AP receives encapsulation by WLAN interface.In the embodiment of Figure 10, modulator-demodulator 1010 receives the grouping after encapsulation by cable system 1040 (such as coax network) at WLAN interface 1017 places.
Then, modulator-demodulator carries out decapsulation to received grouping, to extract the composition grouping (1930) that forms the grouping after encapsulation.In the embodiment of Figure 10, PADM 1016 carries out the decapsulation of WLAN grouping and provides the grouping of composition Ethernet to bridger 1014.For example, can be as described and carry out decapsulation for PADM 1076 in the discussion of Figure 16-18 before.
Modulator-demodulator is determined the main frame recipient (1940) that composition grouping will be sent to one or more expections.Can this operation (1940) be carried out together with many operations at the difference place that processes 1900.For example, operation 1940 can be carried out together with operation 1930 or 1950.In the embodiment of Figure 10, bridger 1014 is determined will send to grouping (multiple) main frame.
Then modulator-demodulator sends composition grouping (1950) by Ethernet interface to (multiple) main frame.In the embodiment of Figure 10, bridger 1014 sends composition grouping to Ethernet interface 1015, and Ethernet interface 1015 divides into groups to the one or more transmissions in main frame 11054 and main frame 21056 by ethernet network 1052.
These one or more main frames receive (1960) and process (1970) grouping.Processing can comprise, for example, the multimedia file that personal computer storage receives by internet, or personal digital assistant (PDA) shows that electronic information (also receiving by internet) is watched for user and alternately.
Figure 21-34 are described now.But the description of the represented embodiment in Figure 21-34 is not limited to following discussion.
In order to utilize the ripe hardware and software embodiment of 802.11 protocol stacks, propose to utilize WLAN (WLAN (wireless local area network)) chipset of amendment to utilize WLAN in coaxial cable medium, to transmit the design of 802.11 frames with different frequency bands.Correspondingly, create TDF (time-division function) agreement for such application situation and replace conventional 802.11DCF (distributed coordination function) or PCF (point coordination function) mechanism in MAC (medium access control) layer.As mentioned above, this TDF agreement is based on TDMA (time-division multiplex access), and TDMA is by being that different time slots allows multiple users to share this channel by same channel distribution.Each in TDF STA (station) is used they self time slot in the TDF super frame of being assigned by TDF AP (access point), one after the other transmits fast one by one uplink traffic.For downlink traffic, STA shared channel, and by the destination-address information in frame and their interested addresses are relatively selected to the frame taking them as target.Fig. 5 illustrates in the time existing the individual STA of m (=tdfUplinkTimeSlotNumber) to compete the meeting of up link conveyer, to the time slot allocation of typical TDF super frame simultaneously.
As shown in about Fig. 5, also describing, there is the time slot of tdfTotalTimeSlotNumber fixed number in each TDF super frame, and it is by forming below: one (1) is for the Sync time slot from TDF AP to TDF STA tranmitting data register synchronizing information; One (1) is for sending the contention slots of the registration request that uplink time slot is distributed; TdfUplinkTimeSlotNumber the uplink time slot being used to TDF AP transmission data and some management frames one by one by the TDF STA registering; And tdfDownlinkTimeSlotNumber the downlink time slots being used to STA transmission data and some management frames by TDF AP.Except Sync time slot, all other time slots that are named as public time slot have length and equal the identical duration of tdfCommonTimeSlotDuration.
The value of the duration of definition tdfCommonTimeSlotDuration is to allow: for peak data rate pattern, transmit at least one maximum 802.11PLCP (Physical layer convergence protocol) protocol Data Unit (PPDU) in a standard time slot.The duration tdfSyncTimeSlotDuration of Sync time slot is shorter than the duration of public time slot, and this is because the clock synchronous frame transmitting from TDF AP to TDF STA in this time slot is shorter than 802.11 Frames.
As a result, can calculate by following formula the duration of a TDF super frame that is defined as tdfSuperframeDuration:
tdfSuperframeDuration＝tdfSyncTimeSlotDuration+tdfCommonTimeSlotDuration*(tdfTotalTimeSlotNumber-1)
Relation between tdfTotalTimeSlotNumber, tdfUplinkTimeSlotNumber and tdfDownlinkTimeSlotNumber meets following equation:
tdfTotalTimeSlotNumber＝tdfUplinkTimeSlotNumber
+tdfDownlinkTimeSlotNumber+2
To provide by CATV access network in the practical application situation of data transmission, typically there are two kinds of application at the frequency band reducing with the utilization of WLAN chipset.Application is to utilize this solution that an internet access is provided, and makes to distribute the guarantee time slot for constant data rate and QoS (service quality) to subscriber.Other application are to use this solution to transmit the uplink traffic of fragmentary (sporadic) the user's control message in VoD (video request program) application such as digital television service from subscriber's side direction head end (head-end).
Utilize MAC layer mechanism set forth above, first obtain uplink time slot to the STA of AP registration, in the time slot then distributing, transmit such control message in each super frame.But, because the traffic carrying capacity of such application is very little, STA needs a very little part for time slot for data transmission, and what is more, even during being used to support to there is the some continuous super frame such application, TDF STA of fragmentary traffic carrying capacity, quite likely there is not the traffic carrying capacity that will transmit.Thus, it will be appreciated by those skilled in the art that under some situation, in TDF agreement, utilize previously created and known pure time-division medium access method support that the application of this Second Type may be quite waste.
According to other known embodiments, during the uplink time slot based on contention, there is the fragmentary uplink traffic that will transmit and will use DCF mechanism to send uplink traffic to TDF AP the TDFSTA not distributing to TDF AP registration uplink time slot.
But, due to the intrinsic feature of DCF mechanism, if a TDF STA always obtains conveyer meeting by less contention window, may it will there is the larger chance of access for the channel of uplink traffic transmission than other STA.And correspondingly, for uplink traffic, between those use the TDF STA of the medium access method based on contention, can not realize fair conveyer can distribution.
For supported data service on cable access network and fragmentary user's control message, the disclosure has at least proposed the TDF of two types.The first is used poll and time-division medium to access both, and the second obtains uplink channel with mixed mechanism.Distortion such as using poll and the mixed mechanism based on contention and further combination can be contemplated to, and are considered a part of this disclosure.
With reference to Figure 21, for to thering is the high data rate service that QoS supports and thering is fragmentary data business volume and other of stand-by period (latency) tolerance limit (tolerance) attribute are served the two and provided support, show the TDF of state-of-the-art (state-of-the-art), it comprise for the poll of uplink channel access and time-division medium access mechanism the two.
Having of the proposing TDF that poll and time-division medium access the two adds a time slot (for example, polling time slot) to the time slot of the TDF super frame using in the TDF routine of previous enforcement.
As shown in Figure 21, there is the time slot of tdfTotalTimeSlotNumber fixed number in each TDF super frame, and the detailed enumerate function of the time slot of every type wherein comprising is as follows:
(1) Sync time slot.This Sync time slot refers to synchronization slot, is used to from TDF AP to TDF STA tranmitting data register synchronizing information.
(1) Reg. time slot.TDF STA uses this Reg. time slot (, discovery timeslot) to send registration request to TDF AP.In registration request frame body, TDF STA notice AP its for up link conveyer can operator scheme of obtaining: poll pattern or time merotype.
(1) polling time slot.During this time slot, there is the fragmentary uplink traffic that will transmit and the TDF STA not distributing to TDF AP registration uplink time slot specific PCF (point coordination function) mechanism of describing in detail below using sent to uplink traffic to TDF AP.
downlink time slots.These time slots comprise tdfDownlinkTimeSlotNumber the downlink time slots that TDF AP uses to TDF STA transmission data and some management frames.
time-division uplink time slot.These time slots comprise by the TDF STA registering one by one to having the TDF AP transmission data of high data rate and QoS support and tdfUplinkTimeSlotNumber the uplink time slot that some management frames is used.
The demand of the practical application based on concrete, in most of the cases, the duration of synchronization slot, discovery timeslot, polling time slot, downlink time slots and time-division uplink time slot differs from one another.But the each uplink time slot while being known as tdfUplinkTimeSlotNumber of public time slot in time-division slot has length and equals the identical duration of tdfCommonTimeSlotDuration.
As a result, can be calculated by following formula the duration of a TDF super frame that is defined as tdfSuperframeDuration:
tdfSuperframeDuration＝tdfSyncTimeSlotDuration
+tdfRegTimeSlotDuration
+tdfPollingTimeSlotDuration
+tdfCommonTimeSlotDuration
*(tdfTotalTimeSlotNumber-3)
TdfTotalTimeSlotNumber, tdfUplinkTimeSlotNumber and
Relation between tdfDownlinkTimeSlotNumber meets following equation:
tdfTotalTimeSlotNumber＝tdfUplinkTimeSlotNumber
+tdfDownlinkTimeSlotNumber+3
The PCF routine strengthening in during polling time slot
For having the STA in the two this TDF of poll and time-division medium access mechanism, various embodiments comprise two kinds of operator schemes: one is poll pattern; Merotype when another kind is.
The basic medium access method that STA operates to carry out uplink traffic transmission in poll pattern is PCF.But, due to the particular surroundings that the enterprising line number of the circuit fixing is reportedly sent, this classical PCF mechanism is carried out to some improvement.
Basic access
PCF mechanism in polling time slot provides the frame transmission that avoids contention.With reference to Figure 23, PC (some telegon) 2302 resides in TDF AP 2300.The form that the poll pattern that having identified Capability (ability) information field of Beacon (beacon) frame sending from AP is provided by AP 2300 is supported.The TDF STA 2304 of medium access that need to be based on poll should be in response to the poll that avoids contention receiving from AP 2300 (CF-poll), and being therefore called as can CF-poll.When by PC 2302 poll, STA that can CF poll should only transmit a MPDU (Medium Access Control (MAC) Protocol Data Unit), and this MPDU should be sent to AP and need to not reply this MPDU by AP.AP is the not STA in the polling list of this AP of poll never.
The frame being sent during polling time slot by AP or STA should use suitable frame type based on following service regeulations:
1.AP should be only sends CF-poll to STA that can CF-poll.In this frame, AP does not send data to addressed recipient, and addressed recipient is the next STA sending in being allowed to during this polling time slot; And
2. can send data and empty frame by any STA that can CF-poll.
AP obtains the control to medium and attempts retentive control in whole polling time slot in the beginning of polling time slot.Do not need beginning and end as transmitted respectively Beacon and CF-End and come signaling (signal) polling time slot by AP in classical PCF agreement.
When there is entry (entry) in polling list time, AP should send CF-Poll at least one STA during each polling time slot.During each polling time slot, AP should be from first to last sequentially sends poll to the subset of the STA in polling list.
With reference to Figure 24 and Figure 25, Once you begin each polling time slot, AP should transmit (2506) CF-Poll frame to a STA in polling list.If there is not entry (2502) in polling list, AP should transmit immediately downlink traffic (2504) during this polling time slot, until the end of downlink time slots.
After transmitting, AP receives data or empty frame (2508) afterwards from STA that specifically can CF-poll, or after not obtaining the response of CF-Poll from specific STA in the predefined period after AP transmits, AP should recover to control and can transmit its next CF-Poll frame to next entry in polling list, unless before deserving during polling time slot in the remaining time inadequate.If now, arrive the last entry in polling list, AP next time first entry of attempting from polling list is started, send CF-Poll frame to STA.If remaining deficiency of time is to allow polled STA to transmit the Frame that comprises minimum length MPDU in current polling time slot, AP will not send CF-Poll frame (2510).Alternately, the firm beginning of the polling time slot in during next super frame, AP sends CF-Poll frame by starting to next entry in the polled STA in polling list or the first entry (if polled STA is the last entry in list) in this polling list.
With reference to Figure 24, all STA that can CF poll in poll pattern that are associated with this AP should not transmit any uplink traffic, unless it during this polling time slot in by this AP poll.In poll pattern can CF poll STA should be always in response to the CF-Poll that points to its MAC Address and receive error-free.After receiving this CF-Poll, this STA should transmit a Frame immediately.If STA does not have frame to send when polled, this response should be sky frame.The STA polled, can CF-poll that had insufficient time to the Frame that sends its queuing before the end of polling time slot should respond by transmitting empty frame.
The maintenance of polling list
AP should safeguard " polling list ", the STA that receives CF-Poll in during polling time slot and force the poll of STA that can CF poll for selecting to be applicable to (eligible).Can control the CF-Poll type that Frame used that is sent to STA that can CF poll by AP for transmitting with this polling list.
Once receiving wherein this STA from STA, AP use polling mechanism requirement to access the registration request frame of channel, and when the strategy decision of AP based on arranging in this AP authorized such transfer mechanism to this STA, AP should add an entry to the end of polling list, and this entry comprises MAC Address and the data rate of this STA.On the other hand, receive wherein this STA use polling mechanism to indicate it not access the cancellation frame of channel once AP from STA, AP should delete the corresponding entry of this STA in polling list.If STA expect from time merotype while changing into poll pattern, STA should nullify merotype while exiting by sending to AP, and then sends the registration request with poll pattern instruction and notify AP.
With reference to Figure 22, for the flexibility being provided by DCF and the fairness being provided by PCF are provided, a kind of medium access mechanism of the mixing for uplink traffic has also been described, by STA being utilized to DCF and PCF, the two obtains the conveyer meeting to fragmentary traffic carrying capacity to the medium access mechanism of this mixing, and utilizes for the dedicated time slot of STA and transmit high data rate traffic amount.The detailed time slot allocation of the TDF super frame of diagram to this enhancing in Figure 22.
As directed, there is a fixing tdfTotalTimeSlotNumber time slot in each TDF super frame, and list as follows the detailed function of the time slot of every type wherein comprising:
(1) Sync time slot.This Sync time slot refers to synchronization slot, is used to from TDF AP to TDF STA tranmitting data register synchronizing information.
one (1) uplink time slot based on contention.During this time slot, TDF STA can send registration request to TDF AP.In registration request frame body, TDF STA will notify to AP its for up link conveyer can the operator scheme of obtaining: poll pattern, pattern based on contention or time merotype.Meanwhile, there is the fragmentary uplink traffic that will send and will use specific DCF mechanism to send uplink traffic to TDF AP the TDF STA not distributing to TDF AP registration uplink time slot.
(1) polling time slot.During this time slot, there is the fragmentary uplink traffic that will transmit and will use previously described specific PCF mechanism to send uplink traffic to TDF AP the TDF STA not distributing to TDF AP registration uplink time slot.Generally speaking, TDF STA can notify by corresponding mark being set in the association request frame being sent to TDF AP by TDF STA its operator scheme (, DCF or PCF) to TDF AP.
downlink time slots.These time slots comprise tdfDownlinkTimeSlotNumber the downlink time slots that TDF AP uses to TDF STA transmission data and some management frames.
time-division uplink time slot.These time slots comprise by the TDF STA registering one by one to having the TDF AP transmission data of high data rate and QoS support and tdfUplinkTimeSlotNumber the uplink time slot that some management frames is used.
Based on the demand of practical application, in most of the cases, the duration of synchronization slot, time slot, polling time slot, downlink time slots and time-division uplink time slot based on contention differs from one another.
As a result, can be calculated by following formula the duration of a TDF super frame that is defined as tdfSuperframeDuration:
tdfSuperframeDuration＝tdfSyncTimeSlotDuration
+tdfContentionTimeSlotDuration
+tdfPollingTimeSlotDuration
+tdfCommonTimeSlotDuration
*(tdfTotalTimeSlotNumber-3)
Relation between tdfTotalTimeSlotNumber, tdfUplinkTimeSlotNumber and tdfDownlinkTimeSlotNumber meets following equation:
tdfTotalTimeSlotNumber＝tdfUplinkTimeSlotNumber
+tdfDownlinkTimeSlotNumber+3
For supported data service on cable access network and fragmentary user's control message, present principles proposes to use medium access and the time-division medium based on contention to access both for obtaining uplink channel.
For to thering is the high data rate service that QoS supports and thering is fragmentary data business volume and other of stand-by period tolerance limit attribute are served the two and provided support, propose to comprise for the two the TDF of state-of-the-art of the medium access mechanism based on contention of uplink channel access and time-division medium access mechanism.The following functional descriptions of describing this TDF agreement with blending agent cut-in method in detail.
Cut-in method
The TDF that medium accesses and time-division medium accesses having based on contention of present principles adds a time slot (for example, discovery timeslot) to previous disclosed TDF routine.In Figure 26, illustrate the detailed time slot allocation of the TDF super frame of this enhancing.
As shown in Figure 26, there is the time slot of tdfTotalTimeSlotNumber fixed number in each TDF super frame, and the detailed function of the time slot of every type wherein comprising can be listed below:
-mono-(1) Sync time slot.This Sync time slot refers to synchronization slot, is used to from TDF AP to TDF STA tranmitting data register synchronizing information.
-mono-(1) Reg time slot.Contention slots in the super frame structure of describing in this Reg time slot (, discovery timeslot) and Fig. 5 is (comparable) quite, and TDF STA uses this Reg time slot to send the registration request distributing for uplink time slot to TDF AP.
-mono-(1) uplink time slot based on contention.During this time slot, there is the fragmentary uplink traffic that will send and the TDF STA not distributing to TDF AP registration uplink time slot the specific DCF mechanism of describing in detail below using sent to uplink traffic to TDF AP.
-time-division uplink time slot.These time slots comprise by the TDF STA registering one by one to
There is TDF AP that high data rate and QoS support and send that data and some management frames use
TdfUplinkTimeSlotNumber uplink time slot.
-downlink time slots.These time slots comprise TDF AP and send data and some pipe to TDF STA
TdfDownlinkTimeSlotNumber the downlink time slots that reason frame uses.
In one embodiment, Reg time slot and the uplink time slot based on contention can be combined as to a mixed time slot and carry out improved system performance.This improvement is due to the following fact: two time slots all use compensation (backoff) method based on contention carry out channel access and in most of the cases during Reg time slot, may have little traffic carrying capacity.In addition, in order to give the priority higher than the transmission of Frame to the transmission of registration request frame, can be respectively the CWmin of the contention window of registration request frame and CWmax be defined to such an extent that be less than CWmin and the CWmax of the contention window of Frame.
Person of skill in the art will appreciate that: in 802.11 standards, use " contention window ", and " contention window " represents that STA will wait for how many minimum time slots (mini-slot) before attempting access wireless medium, 9 microseconds typically, and then STA will determine whether this medium can be used for transmitting data.By means of example, by 0 and CWmin between select random offset value (backoffnumber) initially to determine accurate contention window number.Each compensation period stops (expire), and indicating channel is still busy, STA by the mode to increase 0 and [CWmin, CWmax] in number between select randomly another compensation period, to the last selected 0 and CWmax between the compensation period.
By respectively the CWmin of the contention window of registration request frame and CWmax being defined littlely than the CWmin of the contention window of Frame and CWmax,, (CWmin of registration) < (CWmin of Frame) and (CWmax of registration) < (CWmax of Frame), guaranteed that the transmission of registration request frame has higher priority than the transmission of Frame.As explained below, this higher priority is because the fewer object compensation period in during less contention window can be used.
Based on the demand during practical application, in most of the cases, the duration of synchronization slot, discovery timeslot, uplink time slot, time-division uplink time slot and downlink time slots based on contention differs from one another.But the each uplink time slot while being known as tdfUplinkTimeSlotNumber of public time slot in time-division slot has its length and equals the identical duration of tdfCommonTimeSlotDuration.
As a result, can be calculated by following formula the duration of a TDF super frame that is defined as tdfSuperframeDuration:
tdfSuperframeDuration＝tdfSyncTimeSlotDuration
+tdfRegTimeSlotDuration
+tdfContentionTimeSlotDuration
+tdfCommonTimeSlotDuration
*(tdfTotalTimeSlotNumber-3)
Relation between tdfTotalTimeSlotNumber, tdfUplinkTimeSlotNumber and tdfDownlinkTimeSlotNumber meets following equation:
tdfTotalTimeSlotNumber＝tdfUplinkTimeSlotNumber
+tdfDownlinkTimeSlotNumber+3
In addition, in TDF super frame, the number of the uplink time slot distributing of TDF STA can be changed into tdfMaximumUplinkTimeSlotNumber from 0.Correspondingly, the available duration of the downlink time slots in TDF super frame can be changed into (tdfCommonTimeSlotDuration* (tdfTotalTimeSlotNumber-3-tdfMaximumUplinkTimeSlotNumber)) from (tdfCommonTimeSlotDuration* (tdfTotalTimeSlotNumber-3)).At every turn in the time there is a TDF STA of request uplink time slot, TDFAP will draw one or more public time slots from available downlink time slots, and then give this TDF STA by these time slot allocation, as long as the number of uplink time slot will be no more than tdfMaximumUplinkTimeSlotNumber after this.
In addition; although the duration of downlink time slots equals (tdfCommonTimeSlotDuration*tdfDownLinkTimeSlotNumber); but between the border of these public time slots, be not to there is guard time, this be because these downlink time slots be continuous and from one independently AP send traffic carrying capacity.In this way, in this agreement, can greatly improve efficiency and the channel utilization that down link transmits.
The DCF routine of the enhancing of the uplink time slot based on contention
For the STA having in the two TDF of medium access mechanism based on contention and time-division medium access mechanism, some embodiments have two kinds of operator schemes: a kind of is pattern based on contention; Merotype when another kind is.
It is the DCF defining in 802.11 specifications that STA operates the basic medium access method that carries out uplink traffic transmission in the pattern based on contention, and this 802.11 specification is by being used CSMA/CA (having the carrier sense multichannel access avoiding conflict) and the random make-up time of following after busy medium situation to allow automatic medium shared.But, due to the particular surroundings that the data on fixing circuit transmit, the DCF mechanism of this classics is carried out to some improvement.
The routine of random back-off
The TDF STA of transmission that expects initialization frame should call (invoke) carrier sense mechanism (physical carrier sensing in most of the cases) determine medium busy/idle condition.If medium is busy, STA should postpone until determine that this medium is not interrupted the ground free time in the time period of definition.After the free time of this medium, then STA should be to generating the random compensation period additional retardation time before transmitting, unless compensation timer has comprised nonzero value, in this case, the selection that does not need to select random number and do not carry out random number.This processing minimizes the conflict between the contention-free period between the multiple STA that postpone till identical string part (event).
Backoff?Time＝Random()*aSlotTime
Wherein, Random ()=from interval [0, CW] on the pseudorandom integer that is uniformly distributed extraction, wherein CW is the integer in the scope of the value of aCWmin and the value of aCWmax, aCWmin <=CW <=aCWmax.
The set of CW value should be the aCWmin value that starts from application-specific, subtracts 1 and sequentially increases, and continue upwards and comprise the aCWmax value of application-specific with 2 integer power.More specifically, for most of applied environments of this agreement, known in advance as the maximum number of the STA in the pattern based on contention of tdfMaximumContentionStationNumber, and can, by manually configuring and/or notifying TDF STA from the management frames of TDF AP broadcast, make aCWmax value can be set to the multiple of tdfMaximumContentionStationNumber or tdfMaximumContentionStationNumber.Thus, when with aCWmax numerical value wherein by the situation of blind setting relatively time, STA can access physical medium after the relatively short make-up time.
By reducing the size of contention window of registered frame, the number of available compensation period will be less than the number of the compensation period that can be used for Frame, and this causes registered frame to have higher priority.
Reply routine
For time the TDF STA that operates in merotype, in during the uplink time slot of distributing separately to this specific STA, in cable environment instead of aloft, exchange and be derived from the frame of STA, thereby transmit these frames in the mode that avoids contention with extraordinary signal quality.As a result, the reliability of sending of mac frame is replied (ACK) frame and is guaranteed in unnecessary definition.
But, for the TDF STA operating in the pattern based on contention, because the difference between cable environment and wireless channel, the carrier sense mechanism of physics is worked and is not fine on fixing circuit, makes the station problem of hiding by the many conflicts between the different TDF STA that cause in contention mode.As the mode of reply the type fault, present principles has proposed to use sure (positive) acknowledgement mechanism.
Correspondingly, exist and can be used for replying of (deploy) two types that dispose:
If TDF AP receive be derived from the STA of the TDF in contention mode uplink frame just
Carry out sure replying from this AP immediately, result, if do not receive ACK, TDF STA scheduling retransfers.
2. an ACK mechanism, its by by some reply assemble be the efficiency of improving channel in a frame.
There is the piece Ack mechanism of two types: immediately with postpone.
TDF AP, after the some uplink frame that receive from the TDF STA in contention mode, sends piece Ack immediately immediately, and piece Ack is immediately suitable for the traffic carrying capacity of high bandwidth and low latency.
Receive in response to some successes, during the specific time slot based on contention in from the uplink frame of TDF STA transmission, the piece Ack of the firm beginning transmission lag of the downlink time slots by TDF AP in the super frame identical with uplink time slot based on contention.For the application of medium stand-by period of tolerance, this is suitable, and by for thering is the most applications of this TDF agreement of medium access control based on contention and time-division medium access control.Piece ACK frame can be the unicast frame to a specific TDF STA in contention mode, to successfully receive uplink frame to this TDF STA notice from it, and piece ACK frame can be also broadcast frame or multicast frames, to successfully receive uplink frame to a large amount of TDF STA notices in contention mode from these STA.
Mode transitions routine
For example, once TDF STA starts (, in the time of initialization), it enters the pattern based on contention acquiescently.Then, depend on its application demand, configuration and/or the service level agreement with service provider, it can be sending registered frame and receive merotype enter after having the registration response that access permits time to TDF AP.
In Figure 27, illustrate from the pattern based on contention to time merotype conversion.As directed, when in pattern 2710 based on contention, the determining of merotype (2712) while whether needing to enter.When answering when "Yes", carry out follow-up about definite (2714) that whether received sure response at TDF STA after TDF AP sends registration request.If received sure response, merotype in the time that 2716 enter.If determine 2712 or 2714, to cause negate that system remains on the pattern 2710 based on contention.
Contrary with the embodiment shown in Figure 27, TDF STA can be within its operating period from time merotype enter the pattern based on contention.In Figure 28, illustrate this design.As directed, when in time merotype 2802 in time, carry out about determine (2804) that whether need to enter pattern based on contention.If "Yes", sends de-registration request (2806), and enter the pattern 2808 based on contention.Under the situation that does not need to enter the pattern based on contention (2804), when system remains in merotype 2802.
Attention: similarly process the embodiment that can be applicable to poll.For example, when needed, embodiment can poll pattern and time switch between merotype.
As above, in order to provide bi-directional data to one's profit to transmit solution on existing coaxial cable access network network, propose to utilize ripe commercialization (commodity) the WiFi chipset with foreign frequency change-over circuit to carry out the method that frame is sent.Adopt the system of the method to be known as ADoC (asymmetric data transmission on coaxial cable) system, wherein in cable access network, must dispose ADoC access point (AP) and the station (STA) of deferring to TDF (time-division function) agreement.As used herein, term " ADoC system " and " TDF system " can be exchanged.AP is connected (referring to Fig. 1) via the splitter in hierarchical tree with STA.In this way, user is in and can accesses remote I P core network via cable access network.Fig. 1 illustrates detailed network topology.
In this typical infrastructure access network framework, ADoC (TDF) access point (AP) of TDF agreement is deferred in existence, and this ADoC access point has an Ethernet interface (AP is connected with IP core network by it) and a coaxial cable interface (AP is connected with cable access network by it).At the other end of access network, ADoC (TDF) STA of TDF agreement is deferred in existence, it is connected with cable access network via coaxial cable interface and via wave point (for example, WLAN (WLAN (wireless local area network)) interface) or wireline interface (for example, Ethernet interface) be connected with house LAN (local area network (LAN)).
With reference to Figure 29, for embodiment of the present invention of the hardware implementation scheme of ADoC STA 2900, two equipment (ADoC equipment 2903 and wlan device 2904) are integrated into binding (colligate) STA.ADoC equipment 2903 will be connected to support the bidirectional data communication in cable system with coaxial cable interface 2906, and wlan device 2904 will be connected to support the bidirectional data communication in wlan network with antenna 2908.If needed, STA 2900 will exchange (swap) Frame between ADoC equipment 2903 and wlan device 2904, to the PC in wlan network can be entered the Internet via ADoC STA.
The STA framework presenting in Figure 29 need to be used for channel coder/decoder and data processing two independently equipment provide internet access function to the personal computer of the WLAN of family.Present principles provides to be utilized one independently dual mode device and the solution that can periodically switch between ADoC pattern and WLAN pattern provides the identical access function to local network.
The double mode ADoC equipment of present principles can support ADoC pattern and WLAN pattern the two and can periodically between these two kinds of patterns, switch.In ADoC pattern, this dual mode device is operating as ADoC STA; And in WLAN pattern, it is operating as WLANAP.
By using the solution of single dual mode device of present principles, instead of two equipment in the classical solution shown in Figure 29, embed and have the ADoC STA of this double mode ADoC equipment that the internet access function to local network can be provided.As a result, compared with the classical solution of two equipment shown in Figure 29, the ADoC that the internet access with via cable access network can be supported
The manufacturing cost of STA reduces almost half of original cost.
In order to realize the dual mode device 2902 of present principles, revise the ADoC equipment 2903 of standard and on the basis of ripe wlan device, carried out evolution (evolve).It is mainly different aspect two from wlan device 2904: 1) aspect physical implementation, its RF is in ADoC frequency band (approximately 1GHz) instead of standard 802.11 frequency bands (approximately 2.4GHz) operation; And 2) at MAC (medium access control) layer, it does not utilize conventional 801.11DCF (distributed coordination function) or PCF (point coordination function) mechanism to exchange mac frame.But it uses the TDF agreement based on time-division multiple access (TDMA) (TDMA) method to transmit mac frame.
As shown in Figure 30, double mode ADoC equipment 2902 is connected with coaxial cable interface 2906 with cable access of internet interlock, and simultaneously, be connected to support the bidirectional data communication in wlan network with antenna 2908.If needed, ADoC STA 2900 receives exchange during these two kinds of patterns Frame from this double mode ADoC equipment 2902.
The hardware structure of double mode ADoC equipment
According to a hardware implementation scheme at the double mode ADoC equipment 2902 shown in Figure 31, switch (switch) 3102 is provided, this switch is the circuit that is configured to switching between WLAN RF circuit 3104 and ADoC RF circuit 3106.Can control switch 3102 by MAC layer software.This embodiment need to be revised WLAN chipset and add switch 3102 to amended chipset.
According in another hardware implementation scheme shown in Figure 32, can with the adjacency of the MAC baseband portion 3100 of equipment aspect change the position of switch 3102.In this embodiment, the frequency band (as the output of WLAN RF 3104 and be approximately 2.4GHz) that transducer 3108 has reduced WLAN is to ADoC frequency spectrum (be approximately 1GHz and can arrive relatively long distance in coaxial cable).Note, MAC baseband portion 3100 can be to be characterized as to be configured to communication equipment that subscriber equipment can be communicated by letter with double mode ADoC equipment 2902.
Contrary with the embodiment of Figure 31, the embodiment of Figure 32 is outside existing WLAN chipset, and similarly, does not need to revise WLAN chipset.
The MAC layer routine of double mode ADoC equipment
In double mode ADoC equipment 2902, basic cut-in method is TDF agreement, and it is identical with the mac-layer protocol of ADoC equipment 2903.
As shown in figure 34, there is a fixing tdfTotalTimeSlotNumber time slot in each TDF super frame, and it is by forming below: one for the Sync time slot from ADoC AP to ADoC STA tranmitting data register synchronizing information; One for sending the contention slots of the registration request that uplink time slot is distributed; TdfUplinkTimeSlotNumber the uplink time slot being used to ADoC AP transmission data and some management frames one by one by the ADoC STA registering; And tdfDownlinkTimeSlotNumber the downlink time slots being used to STA transmission data and some management frames by ADoC AP.
Utilize this TDF agreement, double mode ADoC equipment 2902 in STA pattern for example, by just at Sync time slot, contention slots, the uplink time slot that distributes, (, time slot k) and be (active) activating during downlink time slots.At remaining time slot {, from time slot 2 to time slot k; And from time slot k to time slot m}, double mode ADoC equipment in STA pattern will be nonactivated in ADoC interface section, and result, if there is the available switch of the RF of operation being changed into WLAN frequency band from ADoC frequency band that is controlled to, can be switched to WLANAP pattern.
Detailed MAC layer routine in double mode ADoC equipment is as follows:
1. for example, once ADoC STA is activated and has successfully been distributed the uplink time slot that transmits for uplink traffic (, k), whether dual mode device will calculate k > (m+2)/2 to time slot.If k>=(m+2)/2, mean by T [time slot 2, time slot k)the duration of instruction, [time slot 2, time slot k) at least equaled by T (time slot k, time slot m]instruction duration (time slot k, time slot m].As a result, double mode ADoC equipment will be chosen in [time slot 2, time slot operates in WLAN pattern in k) during the period; On the other hand, if k is < (m+2)/2 mean T [time slot 2, time slot k)be shorter than T (time slot k, time slot m].Therefore, double mode ADoC equipment will be chosen in (time slot k, time slot m] operate in WLAN pattern in during the period.
Note, determine period [time slot 2, time slot k) whether be greater than the period (time slot k, time slot m] produced criterion (k-2) > (m-k), this has produced criterion k > (m+2)/2 then.In addition, in described embodiment, choose WLAN pattern is used for the longer period.But other embodiments, or repeatedly change in WLAN pattern in shorter period manipulate in super frame between pattern.
2. determine at [time slot 2 at double mode ADoC equipment, under situation when time slot operates in WLAN pattern in k) during the period, for other time slots in TDF super frame, double mode ADoC equipment will operate in ADoC pattern and move in the mode of the ADoC TDF agreement of establishing criteria as ADoC STA.Like this, in the time that double mode ADoC equipment enters time slot 2 under ADoC pattern, it frequency of operation is changed into WLAN frequency spectrum, and serves as WLAN AP by configuration RF switch 3102.Then the WLAN routine that, this double mode STA can establishing criteria is communicated by letter with the WLANSTA in house wlan network.
Along with the time continues and approaches time slot k, and before the beginning of time slot k, there is no the time of residue at least one WLAN frame exchange, all STA in house WLAN are sent CTS (clear to send) signal by dual mode device 2902.Duration field in CTS frame will equal time slot k from this super frame duration to the time slot 2 in next super frame.When receiving CTS message, all STA will upgrade their NAV and restriction access WLAN medium in the duration by CTS message report.In this way, dual mode device is by by pretending to make all STA keep mourning in silence within this duration at the time slot k from this super frame to existing another entity to retain this WLAN medium in the period of the time slot 2 in next super frame.After this, this equipment will be controlled switch and will operate frequency spectrum and change back ADoC frequency band and operate according to TDF routine.
Enter in the time slot 2 in next super frame when having arrived dual mode device 2902, equipment 2902 by repeat STA in identical pattern handoff routines and house WLAN also by again bring into use this can with infrastructure WLAN communicate by letter, this is because stop for the duration of mourning in silence of being indicated by CTS simultaneously.
On the contrary, for double mode ADoC equipment wherein determine (time slot k, time slot m] situation while operating in WLAN pattern in during the period, for other time slots in TDF super frame, double mode ADoC equipment will operate in ADoC pattern as STA.In the time that double mode ADoC equipment 2902 enters time slot (k+1) under ADoC pattern, it frequency of operation is changed into WLAN frequency spectrum, and serves as AP by configuration switch 3102.Once the process time slot (m-1) along with time continuation, dual mode device attempts sending cts signal in will be during time slot m, and the beginning that wherein duration field equals the downlink time slots from this super frame is to the duration of the time slot (k+1) in next super frame.After this, dual mode device 2902 by control switch 2002 operation frequency spectrum changed to ADoC frequency band and to operate according to ADoC TDF routine.Thus, as previously described, in the time that dual mode device enters the time slot (k+1) in next super frame, it will carry out identical pattern handoff routines again.
According to an embodiment, the dual mode device of the embodiment of present principles 2902 is for example integrated into, in modulator-demodulator in Figure 10 (, 1010,1020 etc.).Figure 33 shows the example of this embodiment.Equally, when dual mode device 2902 is just operating or when the WLAN communication of positive operative norm (, in the time operating in the suitable time period), this equipment allows user PC to be connected to internet.In this embodiment, pc user will be sent and ask IP address (for example to the request of IP address to modulator-demodulator by process WLAN interface on wireless medium, webpage), and 2) modulator-demodulator via ADoC interface on cable system to ADoC AP, then to router, to this request of the Internet relay.
In this embodiment, dual mode device 2902 comprises ADoC interface or equipment 1018 instead of Ethernet interface.
When (the dual mode device of modulator-demodulator operates in WLAN, wireless mode) time, this filling apparatus is as WLAN AP, and personal computer serves as WLAN station, and wherein dual mode device receives request via the wireless link between modulator-demodulator and personal computer from personal computer.Received request is relayed to bridger by dual mode device, destination-address information in the IP grouping of bridger based on this request determines whether dual mode device need to send this request via the ADoC interface in this dual mode device on cable, or whether definite dual mode device needs this request to be sent to other PC in home network.Then, bridger sends it back request (back down) dual mode device.
For the request for setting up outside connection, dual mode device keeps this request until (dual mode device enters ADoC pattern, have ray mode), dual mode device serves as ADoC station and on cable network, sends out this request to ADoC AP via ADoC interface at this moment.
For for setting up the request being connected with the inside of other PC of home network, dual mode device keeps this request until (dual mode device enters WLAN pattern, wireless mode), it serves as WLAN AP and on wireless medium, sends out this request to destination PC via WLAN interface at this moment.
In the time that other PC in the ADoC AP being associated or the local network of dual mode device from cable system receive any response, will carry out reverse process.
As from aforesaid discussion clearly, in some embodiment at least, can use (for example) public circuit or software to carry out a large amount of processing that are associated with WLAN pattern and ADoC pattern.For example, can carry out the reception to the data from two kinds of patterns and unpack (depacketize) and change between two kinds of patterns by public unit.Need potentially the various application of this conversion to comprise: the modulator-demodulator that (1) receives WLAN pattern input (such as the request to internet access) and uses ADoC pattern that this input is sent from computer, and (2) receive asked internet data and use WLAN pattern these data to be sent to the modulator-demodulator of computer in ADoC pattern.These situations are by the conversion typically relating between different agreement.
The various embodiments of dual mode device enable the communication in one or more patterns with communication unit.Communication unit can comprise, for example, and double mode ADoC equipment 2902, or its part, for example, MAC base band 3100, WLAN RF 3104, and ADoC RF 3106.
Note, modulator-demodulator not only can comprise dual mode device as above, and can comprise and make it possible to the interface that communicates through other networks (except WLAN and ADoC).Other networks like this can comprise for example ethernet network.Correspondingly, modulator-demodulator can comprise the dual mode device 2902 and the Ethernet interface 1015 that for example make it possible to through WLAN and ADoC network service.
Various embodiments (for example) are with a kind of form or another form visit data.Term " access " is used to the term of broad sense, for example comprises and obtains in some way, retrieves, receives, handles (manipulate) or process.Correspondingly, (for example) is the description of the broad sense to possible embodiment to the description of visit data.
The feature of described embodiment and aspect can be applied to various application.Application comprises, for example, as mentioned above, transmits the communication framework (Ethernet-over-cable communication framework) of ethernet signal by use on cable, and individual uses main process equipment and the Internet traffic in their family.But feature described here and aspect can adapt to other application, and correspondingly, other application is possible with foreseeable.For example, user can be positioned at outside their family, such as, be for example located in public place or in their work place.Correspondingly, can use agreement and the communication media except Ethernet and cable.For example, (and using the agreement being associated) transmits and receive data in the following manner, and described mode has fiber optic cables, USB (USB) cable, small computer system interface (SCSI) cable, telephone wire, digital subscriber line/ring (DSL) circuit, satellite connection, sight line (line-of-sight) to connect and honeycomb connects.
Can implement embodiment described here with for example method or processing, device or software program.For example, even if (, discussing as just method) is only discussed in the context of the embodiment of single form, also can for example, implement the feature of discussed embodiment with other form (, device or program).Can carry out device for carrying out said with for example suitable hardware, software and firmware.Can in for example with lower device, implement described method, this device is all is for example often referred to the processor for treatment facility in this way, for example, comprise computer, microprocessor, integrated circuit or programmable logic device.Treatment facility also comprises communication equipment, such as, for example, computer, cell phone, portable/personal digital assistant (" PDA ") and the convenient miscellaneous equipment that carries out information communication between end user.
The embodiment of various processing described here and feature can for example, be embodied in various equipment or application (particularly,, the equipment or the application that are associated with data transmission and reception).The example of equipment comprises video encoder, Video Decoder, Video Codec, the webserver, Set Top Box, laptop computer, personal computer and other communication equipment.As should be clearly, described equipment can be mobile and even be installed in moving vehicle.
In addition, can implement described method by the instruction of being carried out by processor, and such instruction can be stored on the readable medium of processor, such as, for example integrated circuit, software carrier or other memory device (such as, for example hard disk, compact disk, random access memory (" RAM ") or read-only memory (" ROM ")).Described instruction can be formed on the application program of tangible embodiment on the readable medium of processor.As should be clearly, processor can comprise the processor readable medium for example with the instruction for carrying out processing.
About memory device, notice that the various device that runs through described embodiment typically comprises one or more memory devices.For example, although not instruction clearly, modulator-demodulator 1010 and 1020, and AP 1030 (and various other elements) typically comprises one or more for storing the memory cell of data.Storage can be for example electronics, magnetic or optics.
As according to foregoing disclose by obvious, embodiment can also produce the formatted signal with the carrying information that for example can be stored or transmit.Described information can comprise, the data that for example produce for the instruction of manner of execution or by one of described embodiment.Such signal can be formatted as for example electromagnetic wave (for example, using the radio frequency part of frequency spectrum) or be formatted as baseband signal.Described format can comprise stream modulated carrier that encoded data stream for example, data flow according to any in various frame structures after to coding are carried out packetizing (packetize) and utilized packetizing.The information of signaling bearer can be for example analog or digital information.As is known, can transmit signal by various wired or wireless link.

Claims (22)

1. a device of communicating by letter on medium, described device comprises:
Communication unit, for communicating by letter on the medium comprising wireless medium and wire medium, this communication unit can operate in: (1) wireless mode, uses wireless protocols to communicate by letter on wireless medium; And (2) have ray mode, use the modification of described wireless protocols to communicate by letter on wire medium; And
Switch, by described communication unit at wireless mode with have between ray mode and switch,
Wherein during one of two periods in the time slot of time-division function super frame, enter described wireless mode, wherein said time-division function super frame comprises that each public time slot has the identical duration for the synchronization slot of tranmitting data register synchronizing information and multiple public time slot.
2. device according to claim 1, wherein said communication unit comprises:
Communication equipment, is connected to described switch and is configured such that subscriber equipment can communicate with described communication unit;
WLAN (wireless local area network) wlan device, is connected to described switch, and this wlan device is configured to be connected to wireless network via antenna;
Cable network equipment, is connected to described switch, and this cable network equipment is configured to be connected to cable network.
3. device according to claim 2, wherein said cable network equipment is configured to be connected to coax network.
4. device according to claim 1, wherein comprises time-division access mechanism in the modification that has wireless protocols described in ray mode.
5. device according to claim 1, wherein comprises WLAN packet configuration in the modification that has wireless protocols described in ray mode.
6. device according to claim 4, wherein, during at least one time slot distributing in the time slot of time-division function super frame, has the communication of the modification of described wireless protocols under ray mode.
7. device according to claim 1, wherein said communication unit comprises:
WLAN (wireless local area network) wlan device, is connected to described switch;
WLAN antenna, is connected to described switch;
Communication equipment, is connected to described wlan device; And
Transducer, is connected to described switch and is configured to be connected to cable network and is the frequency band that has ray mode by the frequency band conversion of wireless mode.
8. device according to claim 1 wherein enters described wireless mode during the selected long period in described two periods.
9. device according to claim 8, wherein:
The time slot of time-division function super frame further comprises multiple uplink time slots, and
Described two periods are in described multiple uplink time slots.
10. device according to claim 1, wherein said device is the part at time-division function station.
11. devices according to claim 1, wherein said communication unit is further configured to communicates by letter with frame structure, described frame structure is at least supported two kinds of communication patterns, and described communication pattern comprises: time merotype, be wherein the time slot in equipment retention frame structure; With the pattern based on contention, wherein use the contention slots in frame structure to carry out data communication by multiple equipment.
12. devices according to claim 11, wherein said device is the part at time-division function station, and described time-division function station is configured to: use described frame structure by sending data from described time-division function station to time-division function access point during the pattern based on contention in contention slots.
13. devices according to claim 1, wherein said communication unit is further configured to communicates by letter with frame structure, described frame structure is at least supported two kinds of communication patterns, and described communication pattern comprises: time merotype, be wherein the time slot in equipment retention frame structure; And poll pattern, wherein use the polling time slot in described frame structure to carry out data communication by multiple equipment.
14. devices according to claim 13, wherein said frame structure is supported the third communication pattern, described the third communication pattern is the pattern based on contention that wherein uses the contention slots in described frame structure to carry out data communication by multiple equipment.
15. devices according to claim 1, wherein said communication unit is further configured to:
Receive the grouping from the first source, there is specific form from the grouping in the first source;
Receive the grouping from the second source, there is described specific form from the grouping in the second source; And
Be the grouping having after the encapsulation of different-format by the grouping from the first source with from the packet encapsulation in the second source.
16. devices according to claim 15, wherein:
Described specific format comprises ethernet format,
Described different-format comprises the WLAN form that is adapted to wireless transmission,
Described communication unit is further configured to and on coaxial cable, transmits the grouping after encapsulation,
The grouping transmitting after encapsulation comprises:
(a) in the time slot of time division multiplexing scheme, transmit the grouping after encapsulation, and
(b) on the signal of carrying TV data, transmit the grouping after encapsulation according to frequency division multiplex scheme, described frequency division multiplex scheme specifies: transmit the grouping after described encapsulation in the frequency range of the data for after encapsulating, and transmit described TV data in different frequency scope.
17. 1 kinds of methods of communicating by letter on medium, described method comprises:
On the medium that comprises wireless medium and wire medium, communicate by letter, described communication is used with lower one or more: (1) wireless mode, uses wireless protocols to communicate by letter on wireless medium; And (2) have ray mode, use the modification of described wireless protocols to communicate by letter on wire medium; And
At wireless mode with have between ray mode and switch,
Wherein during one of two periods in the time slot of time-division function super frame, enter described wireless mode, wherein said time-division function super frame comprises that each public time slot has the identical duration for the synchronization slot of tranmitting data register synchronizing information and multiple public time slot.
18. methods according to claim 17, wherein:
Described communications packets is contained in wireless mode or has in ray mode received communication data under specific a kind of pattern,
Described switching comprises from specific a kind of pattern described in two kinds of operator schemes and is switched to the another kind of pattern described two kinds of operator schemes, and
It is the agreement being associated with the described another kind of pattern described two kinds of operator schemes by received communication data from the protocol conversion being associated with specific a kind of pattern described in described two kinds of operator schemes that described communication further comprises (1), and transmits received communication data under (2) described another kind of pattern in described two kinds of operator schemes.
19. methods according to claim 17, wherein wired operator scheme is a part for time-division function communication system.
20. 1 kinds of devices of communicating by letter on medium, described device comprises:
For comprising the parts of communicating by letter on the medium of wireless medium and wire medium, describedly can operate in for the parts of communicating by letter: (1) wireless mode, uses wireless protocols to communicate by letter on wireless medium; And (2) have ray mode, use the modification of described wireless protocols to communicate by letter on wire medium; And
For at wireless mode with there are parts that switch between ray mode,
Wherein during one of two periods in the time slot of time-division function super frame, enter described wireless mode, wherein said time-division function super frame comprises that each public time slot has the identical duration for the synchronization slot of tranmitting data register synchronizing information and multiple public time slot.
21. devices according to claim 20, wherein:
Describedly be configured to for the parts of communicating by letter: at wireless mode or there are received communication data under the specific a kind of pattern of ray mode;
Describedly be configured to for the parts that switch: be switched to the another kind of pattern of described two kinds of operator schemes from specific a kind of pattern described in two kinds of operator schemes, and
Describedly further be configured to for the parts of communicating by letter: (1) is the agreement being associated with the described another kind of pattern of described two kinds of operator schemes by received communication data from the protocol conversion being associated with specific a kind of pattern described in described two kinds of operator schemes, and transmits received communication data under (2) another kind of pattern in described two kinds of operator schemes.
22. devices according to claim 20, wherein said wired operator scheme is a part for time-division function communication system.
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Families Citing this family (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP2175590A1 (en) * 2008-10-10 2010-04-14 Thomson Licensing Method and apparatus for communicating over multiple networks
EP2257112A1 (en) * 2009-05-29 2010-12-01 Thomson Licensing, Inc. Time slot allocation method in communication system
CN102377470B (en) * 2010-08-13 2015-08-12 中兴通讯股份有限公司 Reconfigurable radio node and the method with the collaborative work of macrocell WAP (wireless access point)
RU2567873C2 (en) 2011-05-20 2015-11-10 Нек Корпорейшн Transmission device and processing method therefor
US8665704B2 (en) 2011-11-25 2014-03-04 Hewlett-Packard Development Company, L.P. Parallelly coupled stackable network switching device
JP6114027B2 (en) * 2012-12-27 2017-04-12 パナソニック株式会社 Frequency band switching control method and radio communication apparatus
US9661634B2 (en) * 2013-11-01 2017-05-23 Qualcomm Incorporated Systems and methods for improved communication efficiency in high efficiency wireless networks
CN103607662A (en) * 2013-11-21 2014-02-26 乐视致新电子科技（天津）有限公司 Method and apparatus for communication protocol control in intelligent television equipment
CN104158712A (en) * 2014-08-28 2014-11-19 耿直 Time division working method for local area network

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1747483A (en) * 2004-09-06 2006-03-15 华为技术有限公司 Wireless terminal with double mode and realization thereof

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR100403767B1 (en) * 2000-09-01 2003-11-01 주식회사 모리아테크놀로지 Method and system for providing wireless multimedia services by using bluetooth
US7237719B2 (en) * 2003-09-03 2007-07-03 Stmicroelectronics, Inc. Method and apparatus for a USB and contactless smart card device
JP4367941B2 (en) * 2005-01-25 2009-11-18 キヤノン株式会社 Relay device, image supply device, printing system and control method thereof

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1747483A (en) * 2004-09-06 2006-03-15 华为技术有限公司 Wireless terminal with double mode and realization thereof

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