US20120237032A1 - Two-stage block synchronization and scrambling - Google Patents
Two-stage block synchronization and scrambling Download PDFInfo
- Publication number
- US20120237032A1 US20120237032A1 US13/485,749 US201213485749A US2012237032A1 US 20120237032 A1 US20120237032 A1 US 20120237032A1 US 201213485749 A US201213485749 A US 201213485749A US 2012237032 A1 US2012237032 A1 US 2012237032A1
- Authority
- US
- United States
- Prior art keywords
- bits
- synchronization
- module
- pseudo random
- random number
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Abandoned
Links
- 238000000034 method Methods 0.000 claims description 31
- 230000008569 process Effects 0.000 claims description 16
- 230000006870 function Effects 0.000 claims description 11
- 230000005540 biological transmission Effects 0.000 claims description 8
- 238000011084 recovery Methods 0.000 claims description 4
- 238000012546 transfer Methods 0.000 claims description 4
- 238000010586 diagram Methods 0.000 description 14
- 238000004519 manufacturing process Methods 0.000 description 10
- 230000001360 synchronised effect Effects 0.000 description 10
- 238000012545 processing Methods 0.000 description 8
- 230000008878 coupling Effects 0.000 description 6
- 238000010168 coupling process Methods 0.000 description 6
- 238000005859 coupling reaction Methods 0.000 description 6
- 239000000835 fiber Substances 0.000 description 3
- 238000004891 communication Methods 0.000 description 2
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 1
- 230000015556 catabolic process Effects 0.000 description 1
- 229910052802 copper Inorganic materials 0.000 description 1
- 239000010949 copper Substances 0.000 description 1
- 238000006731 degradation reaction Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 230000002349 favourable effect Effects 0.000 description 1
- 238000007620 mathematical function Methods 0.000 description 1
- 230000003068 static effect Effects 0.000 description 1
- 230000007704 transition Effects 0.000 description 1
- 238000012795 verification Methods 0.000 description 1
Images
Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L25/00—Baseband systems
- H04L25/02—Details ; arrangements for supplying electrical power along data transmission lines
- H04L25/03—Shaping networks in transmitter or receiver, e.g. adaptive shaping networks
- H04L25/03828—Arrangements for spectral shaping; Arrangements for providing signals with specified spectral properties
- H04L25/03866—Arrangements for spectral shaping; Arrangements for providing signals with specified spectral properties using scrambling
Definitions
- This invention relates generally to data communications and more particularly to synchronization and scrambling of frames of Ethernet data communications.
- Ethernet is a standard that defines data conveyance protocols for data transmissions and has multiple variations thereof depending on desired data rates and transmission mediums.
- Ethernet standards include 10 BASE-T (10 megabit-per-second (Mbps) data rate over a twisted pair), 10 BASE-F (10 Mbps over a fiber optic cable), 100 BASE-TX (100 Mbps over twisted pairs), 100 BASE-FX (100 Mbps over a fiber optic cable), 1000 BASE-T (1 gigabit-per-second (Gbps) over twisted pairs), 1000 BASE-X (1 Gbps over fiber optic cables), and 10GBase-T (10 Gbps over twisted pairs).
- an Ethernet protocol is often used in a wired local area network (LAN), which typically has a star topology, ring topology, bus topology or hub/tree topology.
- a star topology LAN typically includes a private automatic branch exchange (PABX) and/or a private digital exchange (PDX) to switch voice and/or data between end user devices and/or data terminal equipment (DTE).
- a ring topology LAN passes cable access from one user to another until the users are interconnected in a loop or ring.
- a bus topology LAN typically employs one of the Ethernet protocols to convey data within the network.
- a hub technology LAN is essentially a bus or ring topology with the wiring to a central unit.
- transmitted data must be randomized for proper timing recovery and synchronization.
- Data randomization is typically accomplished by adding digitally generated pseudo-random sequences to the data—a process known as scrambling.
- the pseudo-random sequences repeat after a large number of clock cycles and can either be of self-synchronizing or cipher-stream type.
- Self-synchronizing scramblers have the well known disadvantage of error propagation. Cypher-stream scramblers require a synchronization scheme and, in frame (or block) based transmission, must be synchronized with frame boundaries. If the frame length is not equal to the repeat length of the pseudo-random sequence, degradation of the sequence statistics can occur. This can lead to loss in performance and other undesirable properties.
- FIG. 1 is a schematic block diagram of a portion of a local area network in accordance with the present invention
- FIG. 2 is a schematic block diagram of a portion of another local area network in accordance with the present invention.
- FIG. 3 is a schematic block diagram of a transceiving module in accordance with the present invention.
- FIG. 4 is a schematic block diagram of a synchronization and scramble module in accordance with the present invention.
- FIG. 5 is a schematic block diagram of a synchronization and descramble module in accordance with the present invention.
- FIG. 6 is a schematic block diagram of another embodiment of a synchronization and scramble module in accordance with the present invention.
- FIG. 7 is a schematic block diagram of yet another embodiment of a synchronization and scramble module in accordance with the present invention.
- a two-stage block synchronization and scrambling module includes a synchronization PRNG module, a scramble PRNG module, a summing module, and a storage module.
- the synchronization PRNG module is clocked once per N+1 bit PCS frame (N arbitrary) to produce a synchronization bit and a pseudo-random starting state for the scramble PRNG.
- the scramble PRNG module is clocked N times per PCS frame to produce a cipher stream starting with a pseudo-random state from the synchronization PRNG.
- the summing module is operably coupled to sum the cipher stream and a PCS frame payload to produce scrambled payload.
- the storage module is operably coupled to store the scrambled payload with the synchronization bit.
- Synchronization bits from successive frames are a running bit-serial representation of the synchronization PRNG state and are used by the receiver to synchronize with the transmit scrambler.
- FIG. 1 is a schematic block diagram of a portion of a local area network (LAN) that includes a first device 12 , a second device 14 , and a LAN connection 16 .
- the LAN connection 16 provides local area network connectivity for the first and second devices 12 and 14 to a local area network.
- a local area network may be configured as a star topology, a ring topology, a bus topology or a hub/tree topology.
- Each of the devices 12 and 14 may be a computer, a printer, a filer server, a web server, an email server, an application server, and/or any other type of server including terminal servers. Regardless of the particular construct of the devices 12 and 14 , each device 12 and 14 includes a processing module 18 , 28 , memory 20 , 30 , and a transceiving module 22 , 32 . Each of the processing modules 18 , 28 may be a single processing device or a plurality of processing devices.
- Such a processing device may be a microprocessor, micro-controller, digital signal processor, microcomputer, central processing unit, field programmable gate array, programmable logic device, state machine, logic circuitry, analog circuitry, digital circuitry, and/or any device that manipulates signals (analog and/or digital) based on operational instructions.
- the memory 20 , 30 may be a single memory device or a plurality of memory devices.
- Such a memory device may be a read-only memory, random access memory, volatile memory, non-volatile memory, static memory, dynamic memory, flash memory, cache memory, and/or any device that stores digital information.
- the processing module 18 , 28 implements one or more of its functions via a state machine, analog circuitry, digital circuitry, and/or logic circuitry
- the memory storing the corresponding operational instructions may be embedded within, or external to, the circuitry comprising the state machine, analog circuitry, digital circuitry, and/or logic circuitry.
- Each of the transceiving modules 22 , 32 includes a transmit module 24 , 34 , and a receive module 26 , 36 .
- the transmit module 24 , 34 which will be described in greater detail with reference to FIGS. 3 , 4 , 6 and 7 , is operably coupled to transmit scrambled and synchronized frames on the LAN connection 16 , where the scrambling and synchronization is in accordance with the present invention and the frame formatting is in accordance with one or more LAN standard or other proprietary scheme.
- the frame formatting may be in accordance with IEEE P802.3 an (10GBASE-T), which prescribes a 10Gbps Ethernet operation over 4 wire twisted pair.
- the receive module 26 , 36 which will be described in greater detail with reference to FIGS. 3 and 5 , is operably coupled to receive scrambled and synchronized frames on the LAN connection 16 , where the scrambling and synchronization is in accordance with the present invention and the frame formatting is in accordance with one or more LAN standard or other proprietary scheme.
- the receive module 26 , 36 Upon receiving the scrambled and synchronized frames, the receive module 26 , 36 descrambles the frames to recover the original frames.
- FIG. 2 is a schematic block diagram of a portion of another LAN that includes devices 12 and 14 coupled to a switch/router 25 via LAN connections 16 .
- a LAN may be a data center that may be connected to other networks.
- a data center may be viewed as a cluster of relatively high powered and capable processors (i.e., the devices 12 and 14 ) that may include any one or more of a filer server, a web server, an email server, an application server, and/or any other type of server including terminal servers that are configured in a star type configuration to an Ethernet switch/router 25 .
- the data center may be located in a region such as a building, a campus, or some other finite locale in which a number of networks interface and from which a number of end users are serviced.
- the Ethernet switch/router 25 may also be communicatively coupled to the Internet itself (via any appropriate firewall and Internet-adapted WAN (Wide Area Network) router), or any other WAN as well.
- WAN Wide Area Network
- FIG. 3 is a schematic block diagram of a transceiving module 22 , 32 that includes the transmit module 24 , the receive module 26 , and an optional splitter 45 .
- the transceiving module 22 , 32 functions in a half duplex mode, where the splitter operably couples the transmit module 24 to the LAN connection 16 when the transceiving module 24 , 34 is in a transmit mode and couples the receive module 26 , 36 to the LAN connection 16 when the transceiving module 24 , 34 is in a receive mode.
- the transceiving module 22 , 32 functions in a full duplex module such that the splitter is eliminated and the transmit module 24 , 34 and the receive module 26 , 36 are independently coupled to the LAN connection 16 .
- each coupling may include a twisted pair.
- the transmit module 24 includes a synchronization and scramble module 40 and a PCS (physical coding sublayer) frame generating module 42 .
- the PCS frame generating module 42 is operably coupled to generate PCS frame payloads from data it receives from the processing module of the associated device.
- the PCS frame generating module 42 may generate the PCS frame payload in accordance with one or more Ethernet protocols including, but not limited to, IEEE P802.3an (10GBASE-T).
- the synchronization and scramble module 40 is operably coupled to scramble the PCS frame payload and to provide corresponding synchronization information to produce the scrambled and synchronized frames that are transmitted on the LAN connection 16 .
- the corresponding synchronization information is a synchronization bit generated per frame of the scrambled PCS frame payload.
- the receive module 26 , 36 includes a synchronization and descramble module 44 and a PCS frame recovery module 46 .
- the synchronization and descramble module 44 is operably coupled to receive scrambled and synchronized frames and, based on the synchronization information, descramble the scrambled and synchronized frames to produce recovered frames.
- the PCS frame recovery module 46 receives the recovered frames and recovers original data therefrom in accordance with a standard to which the original frames were created.
- the standard may be one or more versions of the Ethernet standard including, but not limited to, IEEE P802.3an (10GBASE-T).
- FIG. 4 is a schematic block diagram of an embodiment of the synchronization and scramble module 40 that includes a synchronization pseudo random noise generator (PRNG) module 50 , a scramble PRNG module 52 , a summing module 54 , and a storage module 56 .
- the synchronization PRNG module 50 is clocked once per PCS frame to generate and insert a synchronization bit 58 per PCS frame. Synchronization bits from successive frames are a running bit-serial representation of the state of the synchronization PRNG in the transmitter. This enables verification of PCS frame synchronization and fly-wheel re-synchronization in the receive module 26 , 36 .
- the synchronization PRNG module 50 generates state information 60 to indicate at least an initial pseudo-random starting point of the pseudo random noise sequence.
- the scramble PRNG module 52 which is clocked once for each bit (or symbol) in the PCS frame, generates a cipher-scrambling sequence (i.e., a cipher stream) 62 for use within PCS frames.
- the cipher-scrambling sequence may be modulo-2 added to a PCS payload.
- the summing module 54 is operably coupled to sum a PCS (physical coding sublayer) frame payload 64 with the cipher stream 62 to produce a scrambled payload 66 .
- PCS physical coding sublayer
- the storage module 56 is operably coupled to store the scrambled payload 66 in accordance with the synchronization bit 58 .
- the synchronized and scrambled data frame is read from the storage module 56 and provided on the LAN connection 16 . Note that storing and reading operations can proceed in parallel such that the entire PCS frame need not be physically stored.
- FIG. 5 is a schematic block diagram of an embodiment of the synchronization and descramble module 44 that includes a recover synchronization PRNG module 70 , a descramble PRNG module 72 , a subtraction module 74 , and a storage module 76 .
- the operation of the synchronization and descramble module 44 is the inverse of the operation of the synchronization and scramble module 40 .
- the synchronized and scrambled data frame received via the LAN connection 16 is stored in the storage module 76 .
- the recover synchronization PRNG module 70 receives a resynchronization bit 78 , which corresponds to the synchronization bit inserted into the PCS frame and is a running bit-serial representation of the state of transmitter synchronization PRNG 50 . Based thereon, the receiver synchronization PRNG 70 can be synchronized with the transmitter PRNG 50 to generate state information 80 .
- the descramble PRNG module 72 uses the state information 80 to produce a cipher-descrambling sequence (i.e., a decipher stream) 82 for interpreting the scrambled PCS frames.
- the cipher-descrambling sequence may be mod-2 added to a PCS payload and will correspond to the cipher-scrambling sequence produced by the scramble PRNG module 52 .
- the subtraction module 74 subtracts the decipher stream 82 from the scrambled payload 86 to produce recovered PCS frame payload 88 .
- the summing module 54 and the subtraction module 74 may be more complex mathematical function elements.
- the summing module 54 may perform an interleave function and the subtraction module 74 may perform the corresponding deinterleaving function.
- the summing module 54 may function as an encoder where the PCS frame is encoded based on the cipher stream 62 and the subtraction module 74 may be a decoder decoding the scrambled payload based on the decipher stream 82 to recover a PCS frame.
- the summing modules 54 and 74 may implement finite field arithmetic in the case of multi-bit scrambling schemes.
- FIG. 6 is a schematic block diagram of an embodiment of the synchronization and scramble module 40 that includes a 1 st production module 90 , a 2 nd production module 92 , a combining module 94 , and the storage module 56 .
- the synchronization and scramble module 40 may be used in any system in which information is transmitted in frames. For every frame, the synchronization and scramble module 40 conveys one synchronization bit 100 , N payload bits 104 and other bits onto the LAN connection.
- the 1 st production module 90 produces a new synchronization bit 100 for each frame and thereby transitions to a new state. Further at the beginning of each frame, the 2 nd production module 92 is initialized with state bits 98 of theist production module 90 .
- the 2 nd production module 92 is then clocked N times to produce N stream scrambling bits 102 , which are combined with N payload bits 104 of the frame by the combining module to produce a scrambled frame 106 .
- the storage module 56 stores the scramble module 56 for subsequent transmission on the LAN connection.
- FIG. 7 is a schematic block diagram of an embodiment of the synchronization and scramble module 40 that includes a 1 st production module 90 , a 2 nd production module 92 , a combining module 94 , and the storage module 56 .
- the 1 St production module 90 may be realized by a synchronization pseudo random number generator (PRNG) module 52 , which may include a continuously operating Maximum Length Shift Register (MLSR) 110 ;
- the 2 nd production module 92 may be realized by a scramble PRNG module 52 , which may include a continuously operating Maximum Length Shift Register (MLSR) 112 ;
- the combining module 94 may include a modulo-2 adder 114 .
- the Maximum-Length Shift Registers (MLSR) 110 and 112 have feedback connections that are determined by primitive polynomials of degree m 1 and m 2 , respectively, where m 1 and m 2 may be identical.
- the continuously operating MLSR 110 and 112 with primitive-polynomial feedback of degree m, generates a pseudo random binary sequence with period length 2 m -1 comprising 2 m ⁇ 1 ones and 2 m ⁇ 1 -1 zeros.
- the m state bits are the m preceding output bits, and within one period the m-tuple of state bits cycles through all 2 m -1 non-zero binary m-tuples.
- the initialization of the Scramble PRNG 52 defines the starting point of the subsequence of N scrambling bits within the 2 m 2 1-periodic sequence that would be produced in continuous operation.
- the transfer of state bits from the Synchronization PRNG 50 to the Scramble PRNG 52 should occur in a manner such that the subsequences of N scrambling bits start at pseudo-randomly distributed starting points. This can be accomplished in various ways. One possibility is to let the two primitive polynomials be identical with degree m, and reverse the order of the m state bits transferred from the Synchronization PRNG 50 to the Scramble PRNG 52 .
- the Synchronization PRNG 50 generates a 2 m -1-periodic sequence, and the Scramble PRNG 52 produces subsequences of length N starting at pseudo-randomly distributed points within the same 2 m -1-periodic sequence. Since the state bits of the Synchronization PRNG 50 cycle through all 2 m -1 non-zero binary m-tuples, the length-N subsequences will start all 2 m -1 possible starting points.
- the m-bit state of the synchronization PRNG 50 is transmitted in a bit-serial manner, one bit per frame, as the synchronization bit 58 , 100 .
- a similar effect will be achieved by choosing two primitive polynomials of same degree m with time-reversed coefficients relative to each other, and not reversing (i.e., maintained) the order of the transferred m state bits.
- the list of choices may be continued, for example, with pairs of primitive polynomials of same degree and non-time reversed coefficients, or primitive polynomials of different degrees and various ways to transfer state bits.
- the term “substantially” or “approximately”, as may be used herein, provides an industry-accepted tolerance to its corresponding term and/or relativity between items. Such an industry-accepted tolerance ranges from less than one percent to twenty percent and corresponds to, but is not limited to, component values, integrated circuit process variations, temperature variations, rise and fall times, and/or thermal noise. Such relativity between items ranges from a difference of a few percent to magnitude differences.
- operably coupled includes direct coupling and indirect coupling via another component, element, circuit, or module where, for indirect coupling, the intervening component, element, circuit, or module does not modify the information of a signal but may adjust its current level, voltage level, and/or power level.
- inferred coupling i.e., where one element is coupled to another element by inference
- inferred coupling includes direct and indirect coupling between two elements in the same manner as “operably coupled”.
- the term “compares favorably”, as may be used herein, indicates that a comparison between two or more elements, items, signals, etc., provides a desired relationship. For example, when the desired relationship is that signal 1 has a greater magnitude than signal 2 , a favorable comparison may be achieved when the magnitude of signal 1 is greater than that of signal 2 or when the magnitude of signal 2 is less than that of signal 1 .
Landscapes
- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Spectroscopy & Molecular Physics (AREA)
- Power Engineering (AREA)
- Computer Networks & Wireless Communication (AREA)
- Signal Processing (AREA)
- Synchronisation In Digital Transmission Systems (AREA)
- Time-Division Multiplex Systems (AREA)
Abstract
Description
- The present U.S. Utility Patent Application claims priority pursuant to 35 U.S.C. §120, as a continuation, to the following U.S. Utility Patent Application which is hereby incorporated herein by reference in its entirety and made part of the present U.S. Utility Patent Application for all purposes:
- 1. U.S. Utility application Ser. No. 11/255,698, entitled, “Two-Stage Block Synchronization and Scrambling” (Attorney Docket No. BP4242), filed Oct. 21, 2005, pending, which claims priority pursuant to 35 U.S.C §119(e) to the following U.S. Provisional Patent Application which is hereby incorporated herein by reference in its entirety and made part of the present U.S. Utility Patent Application for all purposes:
-
- a. U.S. Provisional Application Ser. No. 60/624,557, entitled, “Two-Stage Block Synchronization and Scrambling” (Attorney Docket No. BP4242), filed Nov. 3, 2004.
- 1. Technical Field of the Invention
- This invention relates generally to data communications and more particularly to synchronization and scrambling of frames of Ethernet data communications.
- 2. Description of Related Art
- As is known, Ethernet is a standard that defines data conveyance protocols for data transmissions and has multiple variations thereof depending on desired data rates and transmission mediums. For example, Ethernet standards include 10 BASE-T (10 megabit-per-second (Mbps) data rate over a twisted pair), 10 BASE-F (10 Mbps over a fiber optic cable), 100 BASE-TX (100 Mbps over twisted pairs), 100 BASE-FX (100 Mbps over a fiber optic cable), 1000 BASE-T (1 gigabit-per-second (Gbps) over twisted pairs), 1000 BASE-X (1 Gbps over fiber optic cables), and 10GBase-T (10 Gbps over twisted pairs).
- As is also known, an Ethernet protocol is often used in a wired local area network (LAN), which typically has a star topology, ring topology, bus topology or hub/tree topology. A star topology LAN typically includes a private automatic branch exchange (PABX) and/or a private digital exchange (PDX) to switch voice and/or data between end user devices and/or data terminal equipment (DTE). A ring topology LAN passes cable access from one user to another until the users are interconnected in a loop or ring. A bus topology LAN typically employs one of the Ethernet protocols to convey data within the network. A hub technology LAN is essentially a bus or ring topology with the wiring to a central unit.
- Regardless of the LAN topology, transmitted data must be randomized for proper timing recovery and synchronization. Data randomization is typically accomplished by adding digitally generated pseudo-random sequences to the data—a process known as scrambling. The pseudo-random sequences repeat after a large number of clock cycles and can either be of self-synchronizing or cipher-stream type. Self-synchronizing scramblers have the well known disadvantage of error propagation. Cypher-stream scramblers require a synchronization scheme and, in frame (or block) based transmission, must be synchronized with frame boundaries. If the frame length is not equal to the repeat length of the pseudo-random sequence, degradation of the sequence statistics can occur. This can lead to loss in performance and other undesirable properties.
- Therefore, a need exists for a method and apparatus which permits cipher-stream scrambling to be used in frame based data transmission systems with a method for synchronization and a method for maintaining the desired random properties of the scrambling sequence.
- The present invention is directed to apparatus and methods of operation that are further described in the following Brief Description of the Drawings, the Detailed Description of the Invention, and the claims. Other features and advantages of the present invention will become apparent from the following detailed description of the invention made with reference to the accompanying drawings.
-
FIG. 1 is a schematic block diagram of a portion of a local area network in accordance with the present invention; -
FIG. 2 is a schematic block diagram of a portion of another local area network in accordance with the present invention; -
FIG. 3 is a schematic block diagram of a transceiving module in accordance with the present invention; -
FIG. 4 is a schematic block diagram of a synchronization and scramble module in accordance with the present invention; -
FIG. 5 is a schematic block diagram of a synchronization and descramble module in accordance with the present invention; -
FIG. 6 is a schematic block diagram of another embodiment of a synchronization and scramble module in accordance with the present invention; and -
FIG. 7 is a schematic block diagram of yet another embodiment of a synchronization and scramble module in accordance with the present invention. - In general, a two-stage block synchronization and scrambling module includes a synchronization PRNG module, a scramble PRNG module, a summing module, and a storage module. The synchronization PRNG module is clocked once per N+1 bit PCS frame (N arbitrary) to produce a synchronization bit and a pseudo-random starting state for the scramble PRNG. The scramble PRNG module is clocked N times per PCS frame to produce a cipher stream starting with a pseudo-random state from the synchronization PRNG. The summing module is operably coupled to sum the cipher stream and a PCS frame payload to produce scrambled payload. The storage module is operably coupled to store the scrambled payload with the synchronization bit. Synchronization bits from successive frames are a running bit-serial representation of the synchronization PRNG state and are used by the receiver to synchronize with the transmit scrambler.
-
FIG. 1 is a schematic block diagram of a portion of a local area network (LAN) that includes afirst device 12, asecond device 14, and aLAN connection 16. TheLAN connection 16 provides local area network connectivity for the first andsecond devices - Each of the
devices devices device processing module memory module processing modules memory processing module - Each of the
transceiving modules transmit module receive module transmit module FIGS. 3 , 4, 6 and 7, is operably coupled to transmit scrambled and synchronized frames on theLAN connection 16, where the scrambling and synchronization is in accordance with the present invention and the frame formatting is in accordance with one or more LAN standard or other proprietary scheme. For example, the frame formatting may be in accordance with IEEE P802.3 an (10GBASE-T), which prescribes a 10Gbps Ethernet operation over 4 wire twisted pair. - The receive
module FIGS. 3 and 5 , is operably coupled to receive scrambled and synchronized frames on theLAN connection 16, where the scrambling and synchronization is in accordance with the present invention and the frame formatting is in accordance with one or more LAN standard or other proprietary scheme. Upon receiving the scrambled and synchronized frames, the receivemodule -
FIG. 2 is a schematic block diagram of a portion of another LAN that includesdevices router 25 viaLAN connections 16. Such a LAN may be a data center that may be connected to other networks. Generally, a data center may be viewed as a cluster of relatively high powered and capable processors (i.e., thedevices 12 and 14) that may include any one or more of a filer server, a web server, an email server, an application server, and/or any other type of server including terminal servers that are configured in a star type configuration to an Ethernet switch/router 25. The data center may be located in a region such as a building, a campus, or some other finite locale in which a number of networks interface and from which a number of end users are serviced. The Ethernet switch/router 25 may also be communicatively coupled to the Internet itself (via any appropriate firewall and Internet-adapted WAN (Wide Area Network) router), or any other WAN as well. - In such data centers, a common means of connectivity between devices is via hard cabling. The IEEE P802.3an (10GBASE-T) Task Force has been particularly commissioned to develop and standardize a copper 10 Giga-bit Ethernet standard that runs over 4 wire twisted pair cables. This is particularly appropriate for data center applications including the connectivity between end-devices (e.g., any of the servers depicted above and/or network authentication servers) and an Ethernet switch/router within the data center. Such interconnectivity requires very high speed operation for proper support of the traffic within and through the data center.
-
FIG. 3 is a schematic block diagram of atransceiving module module 24, the receivemodule 26, and anoptional splitter 45. In one embodiment, thetransceiving module module 24 to theLAN connection 16 when thetransceiving module module LAN connection 16 when thetransceiving module transceiving module module module LAN connection 16. For example, each coupling may include a twisted pair. - As is also shown, the transmit
module 24 includes a synchronization andscramble module 40 and a PCS (physical coding sublayer)frame generating module 42. The PCSframe generating module 42 is operably coupled to generate PCS frame payloads from data it receives from the processing module of the associated device. The PCSframe generating module 42 may generate the PCS frame payload in accordance with one or more Ethernet protocols including, but not limited to, IEEE P802.3an (10GBASE-T). - The synchronization and
scramble module 40 is operably coupled to scramble the PCS frame payload and to provide corresponding synchronization information to produce the scrambled and synchronized frames that are transmitted on theLAN connection 16. In one embodiment, the corresponding synchronization information is a synchronization bit generated per frame of the scrambled PCS frame payload. The synchronization andscramble module 40 will be described in greater detail with reference toFIGS. 4 , 6 and 7. - The receive
module module 44 and a PCSframe recovery module 46. The synchronization and descramblemodule 44 is operably coupled to receive scrambled and synchronized frames and, based on the synchronization information, descramble the scrambled and synchronized frames to produce recovered frames. The PCSframe recovery module 46 receives the recovered frames and recovers original data therefrom in accordance with a standard to which the original frames were created. For example, the standard may be one or more versions of the Ethernet standard including, but not limited to, IEEE P802.3an (10GBASE-T). -
FIG. 4 is a schematic block diagram of an embodiment of the synchronization andscramble module 40 that includes a synchronization pseudo random noise generator (PRNG)module 50, ascramble PRNG module 52, a summingmodule 54, and astorage module 56. Thesynchronization PRNG module 50 is clocked once per PCS frame to generate and insert asynchronization bit 58 per PCS frame. Synchronization bits from successive frames are a running bit-serial representation of the state of the synchronization PRNG in the transmitter. This enables verification of PCS frame synchronization and fly-wheel re-synchronization in the receivemodule synchronization PRNG module 50 generatesstate information 60 to indicate at least an initial pseudo-random starting point of the pseudo random noise sequence. - The
scramble PRNG module 52, which is clocked once for each bit (or symbol) in the PCS frame, generates a cipher-scrambling sequence (i.e., a cipher stream) 62 for use within PCS frames. The cipher-scrambling sequence may be modulo-2 added to a PCS payload. - The summing
module 54 is operably coupled to sum a PCS (physical coding sublayer) frame payload 64 with thecipher stream 62 to produce a scrambledpayload 66. - The
storage module 56 is operably coupled to store the scrambledpayload 66 in accordance with thesynchronization bit 58. In the transmit mode, the synchronized and scrambled data frame is read from thestorage module 56 and provided on theLAN connection 16. Note that storing and reading operations can proceed in parallel such that the entire PCS frame need not be physically stored. -
FIG. 5 is a schematic block diagram of an embodiment of the synchronization and descramblemodule 44 that includes a recoversynchronization PRNG module 70, adescramble PRNG module 72, asubtraction module 74, and astorage module 76. In general, the operation of the synchronization and descramblemodule 44 is the inverse of the operation of the synchronization andscramble module 40. - In operation, the synchronized and scrambled data frame received via the
LAN connection 16 is stored in thestorage module 76. The recoversynchronization PRNG module 70 receives aresynchronization bit 78, which corresponds to the synchronization bit inserted into the PCS frame and is a running bit-serial representation of the state oftransmitter synchronization PRNG 50. Based thereon, thereceiver synchronization PRNG 70 can be synchronized with thetransmitter PRNG 50 to generatestate information 80. Thedescramble PRNG module 72 uses thestate information 80 to produce a cipher-descrambling sequence (i.e., a decipher stream) 82 for interpreting the scrambled PCS frames. The cipher-descrambling sequence may be mod-2 added to a PCS payload and will correspond to the cipher-scrambling sequence produced by thescramble PRNG module 52. - The
subtraction module 74 subtracts the decipherstream 82 from the scrambledpayload 86 to produce recoveredPCS frame payload 88. As one of ordinary skill in the art will appreciate, the summingmodule 54 and thesubtraction module 74 may be more complex mathematical function elements. For example, the summingmodule 54 may perform an interleave function and thesubtraction module 74 may perform the corresponding deinterleaving function. As a further example, the summingmodule 54 may function as an encoder where the PCS frame is encoded based on thecipher stream 62 and thesubtraction module 74 may be a decoder decoding the scrambled payload based on the decipherstream 82 to recover a PCS frame. Further, the summingmodules -
FIG. 6 is a schematic block diagram of an embodiment of the synchronization andscramble module 40 that includes a 1stproduction module 90, a 2ndproduction module 92, a combiningmodule 94, and thestorage module 56. In general, the synchronization andscramble module 40 may be used in any system in which information is transmitted in frames. For every frame, the synchronization andscramble module 40 conveys onesynchronization bit 100,N payload bits 104 and other bits onto the LAN connection. The 1stproduction module 90 produces anew synchronization bit 100 for each frame and thereby transitions to a new state. Further at the beginning of each frame, the 2ndproduction module 92 is initialized withstate bits 98 oftheist production module 90. The 2ndproduction module 92 is then clocked N times to produce Nstream scrambling bits 102, which are combined withN payload bits 104 of the frame by the combining module to produce a scrambledframe 106. Thestorage module 56 stores thescramble module 56 for subsequent transmission on the LAN connection. -
FIG. 7 is a schematic block diagram of an embodiment of the synchronization andscramble module 40 that includes a 1stproduction module 90, a 2ndproduction module 92, a combiningmodule 94, and thestorage module 56. In this embodiment, the 1Stproduction module 90 may be realized by a synchronization pseudo random number generator (PRNG)module 52, which may include a continuously operating Maximum Length Shift Register (MLSR) 110; the 2ndproduction module 92 may be realized by ascramble PRNG module 52, which may include a continuously operating Maximum Length Shift Register (MLSR) 112; and the combiningmodule 94 may include a modulo-2adder 114. - In this embodiment, the Maximum-Length Shift Registers (MLSR) 110 and 112 have feedback connections that are determined by primitive polynomials of degree m1 and m2, respectively, where m1 and m2 may be identical. The continuously operating
MLSR 110 and 112, with primitive-polynomial feedback of degree m, generates a pseudo random binary sequence with period length 2m-1 comprising 2m−1 ones and 2m−1-1 zeros. The m state bits are the m preceding output bits, and within one period the m-tuple of state bits cycles through all 2m-1 non-zero binary m-tuples. - The initialization of the
Scramble PRNG 52 defines the starting point of the subsequence of N scrambling bits within the 2m2 1-periodic sequence that would be produced in continuous operation. For given primitive polynomials, the transfer of state bits from theSynchronization PRNG 50 to theScramble PRNG 52 should occur in a manner such that the subsequences of N scrambling bits start at pseudo-randomly distributed starting points. This can be accomplished in various ways. One possibility is to let the two primitive polynomials be identical with degree m, and reverse the order of the m state bits transferred from theSynchronization PRNG 50 to theScramble PRNG 52. Then theSynchronization PRNG 50 generates a 2m-1-periodic sequence, and theScramble PRNG 52 produces subsequences of length N starting at pseudo-randomly distributed points within the same 2m-1-periodic sequence. Since the state bits of theSynchronization PRNG 50 cycle through all 2m-1 non-zero binary m-tuples, the length-N subsequences will start all 2m-1 possible starting points. The m-bit state of thesynchronization PRNG 50 is transmitted in a bit-serial manner, one bit per frame, as thesynchronization bit - A similar effect will be achieved by choosing two primitive polynomials of same degree m with time-reversed coefficients relative to each other, and not reversing (i.e., maintained) the order of the transferred m state bits. The list of choices may be continued, for example, with pairs of primitive polynomials of same degree and non-time reversed coefficients, or primitive polynomials of different degrees and various ways to transfer state bits.
- As one of ordinary skill in the art will appreciate, the term “substantially” or “approximately”, as may be used herein, provides an industry-accepted tolerance to its corresponding term and/or relativity between items. Such an industry-accepted tolerance ranges from less than one percent to twenty percent and corresponds to, but is not limited to, component values, integrated circuit process variations, temperature variations, rise and fall times, and/or thermal noise. Such relativity between items ranges from a difference of a few percent to magnitude differences. As one of ordinary skill in the art will further appreciate, the term “operably coupled”, as may be used herein, includes direct coupling and indirect coupling via another component, element, circuit, or module where, for indirect coupling, the intervening component, element, circuit, or module does not modify the information of a signal but may adjust its current level, voltage level, and/or power level. As one of ordinary skill in the art will also appreciate, inferred coupling (i.e., where one element is coupled to another element by inference) includes direct and indirect coupling between two elements in the same manner as “operably coupled”. As one of ordinary skill in the art will further appreciate, the term “compares favorably”, as may be used herein, indicates that a comparison between two or more elements, items, signals, etc., provides a desired relationship. For example, when the desired relationship is that signal 1 has a greater magnitude than
signal 2, a favorable comparison may be achieved when the magnitude of signal 1 is greater than that ofsignal 2 or when the magnitude ofsignal 2 is less than that of signal 1. - The preceding discussion has presented a method and apparatus for synchronizing and scrambling frames within an Ethernet-based network. As one of ordinary skill in the art will appreciate, other embodiments may be derived from the teachings of the present invention without deviating from the scope of the claims.
Claims (20)
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US13/485,749 US20120237032A1 (en) | 2004-11-03 | 2012-05-31 | Two-stage block synchronization and scrambling |
Applications Claiming Priority (3)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US62455704P | 2004-11-03 | 2004-11-03 | |
US11/255,698 US8213611B2 (en) | 2004-11-03 | 2005-10-21 | Two-stage block synchronization and scrambling |
US13/485,749 US20120237032A1 (en) | 2004-11-03 | 2012-05-31 | Two-stage block synchronization and scrambling |
Related Parent Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US11/255,698 Continuation US8213611B2 (en) | 2004-11-03 | 2005-10-21 | Two-stage block synchronization and scrambling |
Publications (1)
Publication Number | Publication Date |
---|---|
US20120237032A1 true US20120237032A1 (en) | 2012-09-20 |
Family
ID=35708394
Family Applications (2)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US11/255,698 Expired - Fee Related US8213611B2 (en) | 2004-11-03 | 2005-10-21 | Two-stage block synchronization and scrambling |
US13/485,749 Abandoned US20120237032A1 (en) | 2004-11-03 | 2012-05-31 | Two-stage block synchronization and scrambling |
Family Applications Before (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US11/255,698 Expired - Fee Related US8213611B2 (en) | 2004-11-03 | 2005-10-21 | Two-stage block synchronization and scrambling |
Country Status (2)
Country | Link |
---|---|
US (2) | US8213611B2 (en) |
EP (1) | EP1655917B1 (en) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20140192097A1 (en) * | 2013-01-10 | 2014-07-10 | Samsung Electronics Co., Ltd. | Display driver circuit and method of transmitting data in a display driver circuit |
Families Citing this family (10)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
FR2898229B1 (en) * | 2006-03-06 | 2008-05-30 | Eads Secure Networks Soc Par A | INTERLACEE CRYPTOGRAPHIC SYNCHRONIZATION |
KR100978865B1 (en) | 2007-02-09 | 2010-08-31 | 삼성전자주식회사 | Method and apparatus for transmitting/receiving of system information in mobile communication system |
US8788552B2 (en) * | 2008-01-25 | 2014-07-22 | Tata Consultancy Services Ltd. | Deterministic random number generator for cryptography and digital watermarking |
US9124462B2 (en) * | 2012-10-25 | 2015-09-01 | Texas Instruments Incorporated | Flexible PRBS architecture for a transceiver |
US20210168131A1 (en) * | 2013-05-14 | 2021-06-03 | Kara Partners Llc | Systems and methods for variable-length encoding and decoding for enhancing computer systems |
CN104426631B (en) * | 2013-09-06 | 2018-03-06 | 华为技术有限公司 | The method and device that data are handled |
JP6740902B2 (en) * | 2014-08-20 | 2020-08-19 | 日本電気株式会社 | Authentication encryption method, authentication decryption method, and information processing apparatus |
EP3939194A4 (en) * | 2019-03-13 | 2022-06-29 | ZTE Corporation | Multi-pilot reference signals |
CN114244474B (en) * | 2021-12-20 | 2024-02-13 | 深圳忆联信息***有限公司 | Scrambling code generation method, device, equipment and storage medium |
GB2619963A (en) * | 2022-06-24 | 2023-12-27 | Data Conv Systems Ltd | A transmitter and a receiver |
Citations (14)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4214206A (en) * | 1977-09-27 | 1980-07-22 | U.S. Philips Corporation | Digital transmission system having direct bit extraction from scrambled bit streams |
US5245661A (en) * | 1992-04-21 | 1993-09-14 | Byeong Gi Lee | Distributed sample scrambling system |
US5963646A (en) * | 1997-03-10 | 1999-10-05 | The Pacid Group | Secure deterministic encryption key generator system and method |
US6052786A (en) * | 1997-07-22 | 2000-04-18 | Fujitsu Limited | Secrecy communication system |
US6069954A (en) * | 1996-05-29 | 2000-05-30 | Moreau; Thierry | Cryptographic data integrity with serial bit processing and pseudo-random generators |
US6339781B1 (en) * | 1998-05-28 | 2002-01-15 | Oki Electric Industry Co., Ltd. | M-sequence generator and PN code generator with mask table for obtaining arbitrary phase shift |
US6389138B1 (en) * | 1998-11-12 | 2002-05-14 | Lucent Technologies Inc. | Method and apparatus for generating a complex scrambling code sequence |
US20020097868A1 (en) * | 2001-01-23 | 2002-07-25 | Dai Watanabe | Pseudorandom number generating apparatus or encryption or decryption apparatus using the same |
US20020129307A1 (en) * | 2001-03-06 | 2002-09-12 | Walker Richard C. | Data communication system with self-test facility |
US6477150B1 (en) * | 2000-03-03 | 2002-11-05 | Qualcomm, Inc. | System and method for providing group communication services in an existing communication system |
US6577689B1 (en) * | 1998-04-24 | 2003-06-10 | Cirrus Logic, Inc. | Timing recovery system for a 10 BASE-T/100 BASE-T ethernet physical layer line interface |
US20050220305A1 (en) * | 2004-04-06 | 2005-10-06 | Kazuhisa Fujimoto | Storage system executing encryption and decryption processing |
US20060045136A1 (en) * | 2004-08-26 | 2006-03-02 | Motorola, Inc. | Crypto-synchronization for secure communication |
US8229108B2 (en) * | 2003-08-15 | 2012-07-24 | Broadcom Corporation | Pseudo-random number generation based on periodic sampling of one or more linear feedback shift registers |
Family Cites Families (14)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4383322A (en) | 1980-05-02 | 1983-05-10 | Harris Corporation | Combined use of PN sequence for data scrambling and frame synchronization in digital communication systems |
JPS6197746A (en) * | 1984-10-15 | 1986-05-16 | インタ−ナショナル ビジネス マシ−ンズ コ−ポレ−ション | Random number generator |
US4771463A (en) | 1986-12-05 | 1988-09-13 | Siemens Transmission Systems, Inc. | Digital scrambling without error multiplication |
JPH0783337B2 (en) | 1988-03-01 | 1995-09-06 | 日本電気株式会社 | Scramble-descramble method |
US5349611A (en) | 1992-11-13 | 1994-09-20 | Ampex Systems Corporation | Recovering synchronization in a data stream |
DE69507080T2 (en) * | 1994-06-07 | 1999-05-27 | Matsushita Electric Ind Co Ltd | Optical information recording medium, optical information recording method, and optical information reproducing apparatus therefor |
US5754651A (en) * | 1996-05-31 | 1998-05-19 | Thomson Consumer Electronics, Inc. | Processing and storage of digital data and program specific information |
US5966450A (en) | 1996-08-13 | 1999-10-12 | Lucent Technologies | Variable mask for encryption generated independently at communications stations |
US6052466A (en) * | 1997-08-28 | 2000-04-18 | Telefonaktiebolaget L M Ericsson (Publ) | Encryption of data packets using a sequence of private keys generated from a public key exchange |
US6282181B1 (en) * | 1998-04-24 | 2001-08-28 | Ericsson Inc | Pseudorandom number sequence generation in radiocommunication systems |
US6731692B1 (en) * | 2000-03-23 | 2004-05-04 | Agere Systems Inc. | Symbol encoding and decoding architecture for trellis-coded modulation in gigabit ethernet |
US7599976B1 (en) * | 2002-11-13 | 2009-10-06 | Metrowerks Corporation | System and method for cryptographic key generation |
US7860254B2 (en) * | 2003-03-13 | 2010-12-28 | Hamdy Soliman | Computer system security via dynamic encryption |
US7206797B2 (en) * | 2003-04-14 | 2007-04-17 | M-Systems Flash Disk Pioneers Ltd. | Random number slip and swap generators |
-
2005
- 2005-10-21 US US11/255,698 patent/US8213611B2/en not_active Expired - Fee Related
- 2005-10-25 EP EP05023322.0A patent/EP1655917B1/en active Active
-
2012
- 2012-05-31 US US13/485,749 patent/US20120237032A1/en not_active Abandoned
Patent Citations (14)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4214206A (en) * | 1977-09-27 | 1980-07-22 | U.S. Philips Corporation | Digital transmission system having direct bit extraction from scrambled bit streams |
US5245661A (en) * | 1992-04-21 | 1993-09-14 | Byeong Gi Lee | Distributed sample scrambling system |
US6069954A (en) * | 1996-05-29 | 2000-05-30 | Moreau; Thierry | Cryptographic data integrity with serial bit processing and pseudo-random generators |
US5963646A (en) * | 1997-03-10 | 1999-10-05 | The Pacid Group | Secure deterministic encryption key generator system and method |
US6052786A (en) * | 1997-07-22 | 2000-04-18 | Fujitsu Limited | Secrecy communication system |
US6577689B1 (en) * | 1998-04-24 | 2003-06-10 | Cirrus Logic, Inc. | Timing recovery system for a 10 BASE-T/100 BASE-T ethernet physical layer line interface |
US6339781B1 (en) * | 1998-05-28 | 2002-01-15 | Oki Electric Industry Co., Ltd. | M-sequence generator and PN code generator with mask table for obtaining arbitrary phase shift |
US6389138B1 (en) * | 1998-11-12 | 2002-05-14 | Lucent Technologies Inc. | Method and apparatus for generating a complex scrambling code sequence |
US6477150B1 (en) * | 2000-03-03 | 2002-11-05 | Qualcomm, Inc. | System and method for providing group communication services in an existing communication system |
US20020097868A1 (en) * | 2001-01-23 | 2002-07-25 | Dai Watanabe | Pseudorandom number generating apparatus or encryption or decryption apparatus using the same |
US20020129307A1 (en) * | 2001-03-06 | 2002-09-12 | Walker Richard C. | Data communication system with self-test facility |
US8229108B2 (en) * | 2003-08-15 | 2012-07-24 | Broadcom Corporation | Pseudo-random number generation based on periodic sampling of one or more linear feedback shift registers |
US20050220305A1 (en) * | 2004-04-06 | 2005-10-06 | Kazuhisa Fujimoto | Storage system executing encryption and decryption processing |
US20060045136A1 (en) * | 2004-08-26 | 2006-03-02 | Motorola, Inc. | Crypto-synchronization for secure communication |
Non-Patent Citations (1)
Title |
---|
Schneier, Bruce; "Applied Cryptography, Second Edition", John Wiley and Sons, 1996, pp.200-201 * |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20140192097A1 (en) * | 2013-01-10 | 2014-07-10 | Samsung Electronics Co., Ltd. | Display driver circuit and method of transmitting data in a display driver circuit |
Also Published As
Publication number | Publication date |
---|---|
EP1655917A3 (en) | 2012-03-28 |
EP1655917B1 (en) | 2013-05-15 |
US20060093146A1 (en) | 2006-05-04 |
US8213611B2 (en) | 2012-07-03 |
EP1655917A2 (en) | 2006-05-10 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US20120237032A1 (en) | Two-stage block synchronization and scrambling | |
US9912442B2 (en) | Techniques to perform forward error correction for an electrical backplane | |
US9942064B2 (en) | Data processing method and apparatus | |
US7076724B2 (en) | System and method for forward error correction | |
US7724903B1 (en) | Framing of transmit encoded data and linear feedback shifting | |
US7761776B1 (en) | Method and apparatus for a modular, programmable cyclic redundancy check design | |
WO2011000257A1 (en) | Parallel frame synchronization scrambling apparatus and de-scrambling apparatus thereof | |
JP6539765B2 (en) | Flexible PRBS Architecture for Transceivers | |
JP7339954B2 (en) | Payload and preamble scrambling in 10 SPE with synchronous and self-synchronous scrambling | |
US20010008001A1 (en) | Switching system and scramble control method | |
US11115141B2 (en) | Wired communications device and method for operating a wired communications device | |
US8638895B2 (en) | Extension of Ethernet PHY to channels with bridged tap wires | |
US11108842B2 (en) | Wired communications device and method for operating a wired communications device | |
CN100477583C (en) | Method and apparatus for frame-based information transmission in system | |
US7359391B2 (en) | Multi-port network interface circuit and related method for scrambling codes of different ports with different seeds and resetting signal transmission of different ports at different times | |
TWI324000B (en) | Two-stage block synchronization and scrambling | |
WO2022017182A1 (en) | Data scrambling method, data descrambling method, and related device | |
JP3637289B2 (en) | Method for encoding a multi-bit data word | |
TWI641238B (en) | Communication system and method | |
Lee | Highly reliable synchronous stream cipher system for link encryption |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
STCB | Information on status: application discontinuation |
Free format text: ABANDONED -- FAILURE TO RESPOND TO AN OFFICE ACTION |
|
AS | Assignment |
Owner name: BANK OF AMERICA, N.A., AS COLLATERAL AGENT, NORTH CAROLINA Free format text: PATENT SECURITY AGREEMENT;ASSIGNOR:BROADCOM CORPORATION;REEL/FRAME:037806/0001 Effective date: 20160201 Owner name: BANK OF AMERICA, N.A., AS COLLATERAL AGENT, NORTH Free format text: PATENT SECURITY AGREEMENT;ASSIGNOR:BROADCOM CORPORATION;REEL/FRAME:037806/0001 Effective date: 20160201 |
|
AS | Assignment |
Owner name: AVAGO TECHNOLOGIES GENERAL IP (SINGAPORE) PTE. LTD., SINGAPORE Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:BROADCOM CORPORATION;REEL/FRAME:041706/0001 Effective date: 20170120 Owner name: AVAGO TECHNOLOGIES GENERAL IP (SINGAPORE) PTE. LTD Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:BROADCOM CORPORATION;REEL/FRAME:041706/0001 Effective date: 20170120 |
|
AS | Assignment |
Owner name: BROADCOM CORPORATION, CALIFORNIA Free format text: TERMINATION AND RELEASE OF SECURITY INTEREST IN PATENTS;ASSIGNOR:BANK OF AMERICA, N.A., AS COLLATERAL AGENT;REEL/FRAME:041712/0001 Effective date: 20170119 |