CA2434698C - Multicasting method and apparatus - Google Patents

Abstract

A scalable architecture is disclosed for delivery of real-time information over a communications network. Embedded into the architecture is a control mechanism (10) that provides for the management and administration (60) of users (40) who are to receive the real-time information. A user (40) chooses to tune in or tune out a particular channel, but does not choose the time at which the channel distributes its information. Advantageously, interactive (two-way) information can be incorporated into the system, multiple streams of information can be integrated for delivery to a user (40), and certain portions of the information being delivered can be tailored to the individual user (40).

Description

MULTICASTTNG METHOD AND APPARA~S
i~ Field of the =avention ...This relates to a method and apparatus for.provid'ing' audio and/or visual c~mmunication servi~;es, ..in real--time to a multiplicity of identifiable ~ users'~on a communications ' network, such as the Internet. In a preferred embodiment, the.inventi.on monitors which users.are receiving signals on which one of . a plurality of channels- arr~ modifies the :content .of a~~ least . some .signals ~in response th~:reto~. ~3 particular .
application ,is to provide services akinvto multi~channel radio or television with commercial, programming content adjusted in accordance~with the identity of the individual user.

3. Background of the Invention Systems such as the ~Int.ernet typically are point-to-point (or unicast, .systems in which -a message, is~ converted into a series ~f addressed packets that are routed .from a . 3p. source .node through a plurality, of roisters ~ to a~ destination node. In most communication protocols the packet~.includes a' header that containa'the addresses of the source and the destination nodes as well as a sequence number that specifies the packetls order in the message:. ..
25 In.general, these systems do not have td~e capability of broadcasting a message from a'source node,.to all the other nodes in the ~ettaork because such a capability is rarely of much~use and could easily overload the network.
However, there are situations where it is desirable for, one 30 node to communicate with some subset of all~the nodes. For example, mufti-party conferencing capability, analogous to that found iw the public telephone system and broadcasting to a.limited number of nodes, is of considerable interest to users of packet-switched networks. To satisfy such demands, 35 packets destined for several recipients have been .
encapswlated in a unicast packet and forwarded from a source.
to a point in a network where the~packets have been replicated and~~forwarded on to all desired recipients. This technique is known as IP Multicasting a~xl the network over which such packets are routed. is referred to as the Multicast Backbone or MBONE.-. More recently, routers~.have become 5:avai.lable that can route the.mu3ticast addresses (clas~ D
addresses),provided for.in communication protocols such a~
TCP/IP and UDP/~P. A multicast address is essentially an address for a group of host computers who have indicated', ~~ their desire to participate in that~group. Thus, a multicast i0 packet can be r~ut~d from a source, node through a plurality of multicast roisters for mrouters) °to one or more devices receiving thc~ multicast packets. From there the packet is distributed to.all the~host computers that are members of the multicast group~.
i5 ~ These techn~.ques ha'~re been used to provide on the Internet~audio and video conferencing as well as radio-like broadcasting to groups of interested parties. See, for example, K. Savets,et al~ MF30NE Multicastina Tomorro~,!s Interns (IDG Books Worldwide xno:, 199fs). .
20 Further details concerning technical aspects of multicasting may be found in the. Internet. documents Request for Comments (RFaC) 1112 and 1458, which are reproduced at Appendices A and ~ ~f the Savetz bo~k and in D.P~ Brutaman et s,x., "MBONE provides Audio axrd Video Across the Internet,"
25 IEEE Comuuter, Vol. 27, No. 4, pp. 3°-36 (April 1~~4), Citation of the foregoing documents is.not to~be construed as an admission that any of such documents is a prior art publication relati~re to the present invention.
sa ~ ~ s , a~ the x~~reat~omm The present invention is-a scalable architecture for delivery of real-time , information. over a communications network. ~nbedded into the architecture is a control 35 mechanism that provides for the management and administration of users who are to receive the real=time information.
o ~ P

~, In the preferred embodiment, the infor$iation being delivered~is high-quality audio. However, it could.also be video, graphics, text or any other_type of infor~atiori that can be transmitted over.a digital netwoyk. ,'his information is delivered in real-time to any number of widely:distributed users. ~It is real-time.in.that for a given channel of information, approximately the same information is being sent at appraximately the same tide to everyone who is:enabled to receive. the information.
to : . Preferably, there are multiple charui~3s' of .
informatio~a available simultaneously to be delivered. to users, each channel consisting of an independent.stream o~f information. A user ~ chooses to tune in or ~ tune out a particular channel, but does not choose the time~at which the ~5 channel distributes its infoz~ination..Advaritageously, interactive (two--way) information can, be incorporated into the system, multiple streams of information can be integrated for delivery to a user, and certain portions'..of~t~e' infozmation being delivered can. be tailored to the 3.ndividual 2o user.
Brief Descripti~a of the DrarrfaQ .
These and other objects, features and.advantages of our invention will be more readily apparent frosi the x5 following Detailed Description of a F~c°efex°red Embodiment of our invention in which: .
Fig. 1 is a schematic diagram depicting ~ari overview of the system of the present invention;
Fig. 2 is a schematic diagram~depicting the network 30 control center for the system of_.Fig. 1~:
Fig. 3 is a sohematic~diagtam depicting a unicast distribution structure;
Fig. 4 is a schematic diagram depicting a multicast distribution structure;
35 Fig. 5~is a schematic diagram depicting the connection. between the media server and the user in the system of Fig. 1;

Figs. 6-1?.are timing diagrams that depict various aspects of the operation of the system of Fig. 1; and Figs. 18 and 19 depict the user interface,for control of the system of. Fig. i: .
Where the sa~ie reference numerals appear ~ in multiple drawings, the numerals refer t~ the same or corresponding structure in such drawings.
5. Detailed Description of- the preferred Embod3.ment Referring to Fig. 1, the syste~a of the present invention comprises a Network Control Center 10, a plurality of Primary Servers 20, Media Servers 30, Users 40 and Control Servers 50 and an administration Server 60. The servers are interconnected by a~coadmunications network, which in..the 15 preferred embodiment is the global connected internetwork - known as.the Internet. The NetworkwControl Center 10 is the source of the information being distributed. It receives audio feeds from satellite, over the air broadcast or in other ways and processes this information for delivery over ~o the network on multiple channels of info~.~nation.. This processing consists of optionally recording the information for future broadcast and dynamically inserting paid commercial advertisements.
Far each channel of information, there is a~Primary 35 Server 20 hat receives the .streax4 of inforaaation from the Network Control Center to and compresses the information Stx'eam t~ allow for more efficient tranSmlsslon. 'fhe Prlm8ry Servers 20 are directly connected. to the network.
The Primary Servers forward information via the 30 network to a number of Media Servers 30. There may be a large number of Media Servers~vand in fact there may be many levels of Media Servers. For examgle, a Media Server that receives a stream of information from a primary Server may forward that stream via the network to another Media Server 35 that then forwards it to a User 4n: This multilevel hierarchical structure is described~:~in more detail below.

The topology of the Internet dictates the ideal placement of Media Servers, the fan-out of each. Media Server and. the number of ~ levels of Media. Servers between the Pricaary -vServer and Users. For example, the Media Servers that~feed from a Primary Server might be placed at major'goints of presence (POPS) of each of the large Internet service.
providers.. These Media Servers might also be placed, near clouds that serve as high bandwidth~exchange points between the major.carriers. Similarly, Media Servers that~~feed to 1~ Users might be placed~on or close to networks.that have a large'number of subscribers to minimize the distance and number of data streams being transmitted.
Control. Servers 50 are responsible for ~Ceeping.
. track of which users are listening. ,to Which charnels and for ~5 directing the Med~awServers to start and stop st.reaias of information to those Users. The Controh~Sezvers are also responsible for handling other interactions among the various components of the system.as will be described in more~detail belo~r. Each Control Server is responsible for. managing a 2A clustes'of Media Servers; and each.Media Server is~managed by a single Control Server, at any given time: As a result, the Control Servers are distributed throughout the Internet, preferably located close to the Media Servers.
The Administration server 60 is responsible for 25 registering neW users:, authenticating users who want to log.
onto the system, and maintaining audit logs for how many Users'are li,stening~to which channels and at which ;times.
Maintaining audit logs and,, gathering statistics-are features critical to monitoring the delivery of paid commercial 30 messages as well as for other purposes. 'For example, .for purposes of assessing copyright r~yalties, the audit logs.cari record the number of listeners for each musical o~c video selection.that is distributed by the system. Another application is to determine the percentage of listeners who 35 are interested in listening to a particular musical selection.
by determining how many listen~to the entire selection at~d hOW many turn it Off~
s 5. w CA 02434698 2003-07-21 .
The system of the present invention can Jbe. .
considered a distribution architecture integrated with a control architecture. The distribution architecture handles scalable real-time delivery of information.to any number of Users on a.packet switched networks such as the Internet.
The control architecture represent~,a~second scalable system integrated with the distribution architecture for.ananaiging and administering the delivexy of that information.
.The remainder.of this description is divided into Ip three~sect~ions. In the pert sectiors~the distribution architecture will be described in ~aore'detail. ~ ~~llowing that, the control architecture will be.described. In the third section the user interface will be illustrated.
t5 I. Distribution i~rchit~cture The distribution, architecture provides~for'the delivery of real-time infor~datiori to any number of Users distributed throughout a network. ~,s will be described in 20 detail below, the distribution architecture~is scalable t~
allow for efficient delivery of multiple simultaneous information~channels in real-time to a urge number of Users.
In the preferred embodiment, the information that is being distributed consists of high-quality audio in~
i5 addition to other information'. It should be appreciated that ' the basic architedture and other general principles set forth herein would~also apply to the delivery of video, graphics, text or any other'type of informatiorA that can be delivered over a digital network. In addition; it should be 3~ appreciated that an information, stream carp consist of audio with supplemental information such as text and graphic images and commands to control software running on the User~s c~mputer a ~ _ , .
The source of inforanation in the preferred 35 embodiment is the Network Control. Center 10, depicted in'the schematic diagram of Fig. 2. Control c:entsss of this type of design,are available from Braadcast Electronics, Inc, and are similar to what would be found in a conventional radio station serving multiple frequencies.
Referring to Fig. 2, the incoming signal can be received in a variety of ways such as from a satellite, over-the-air broadcast, cable or hard disk. It is then processed by Receiver/Decoder 210, which decodes the signal and provides an incoming audio stream. Routing Switcher 120 is respansible for routing the incoming audio feed from the Receiver to either Delay Recording Workstation 340 or to one of the Playback/Control Workstations 130. Real-time insertion of paid commercial advertising takes place at the Playback/Control Workstations and the resulting integrated audio stream is delivered to the Primary Servers. The Delay Recording Workstation is responsible fox recording an i5 incoming broadcast so that it can be played back at a later time.
Supervisory Workstation 154 is responsible for managing and controlling the Playback/Control Workstations, Delay Recording Workstations and other computers as may be connected to the local area network within the Network Control Center. Production Workstation 160 and AudioVAULT-NFS Server 170 are used to manipulate audio samples, such as commercial messages for use by the Playback/Contral Workstations. The audio being delivered can consist of syndicated TV or radio programsf such as would be received over satellite or cable and delivered as described above.
These can be delivered live and/or played bank at a later time. Tt is also possible for the delivery of information, such as music, to take place from information that is all stored locally such as on a hard disko A new play list and its associated music data can then be downloaded periodically to update the channel. Additionally, it is possible to deliver commercial-free programming, for example public service announcements or label-specific music"
In the preferred embodiment the Primary Servers are responsible for compressing the audio stream using an advanced perceptual technique developed and licensed by AT&T
7 _ Corp. and Lucent Technologies, Inc. This highly sophisticated algorithm is used to maximise the benefit of the bandwidth available. Advantageously, two bitrates are available, a first rate of approximately 2oKbps and a second rate of approximately 56Kbps. Using the perceptual technique, the quality of the first rate is similar to FM
monaural (with a sampling rate of approximately 22,00~ 16-bit samples per second) and the second rate is close to CD
quality stereo (with a sampling rate of approximately 32,000 16-bit samples in stereo each second). The signals at the two different bitrates comprise two differen°t audio channels and thus require two different compression p~roaesses.
The computational requirements of compressing an audio stream in real time using techniques such as the advanced perceptual technique are approximately 100% of a Pentium-Pro 20oMhz computer and the computat~.onal requirements of decompressing an audio strewn' in real time are approximately 30% of a Pentium 75Mhz computer. Future improvements and/or changes to the algox°ithm could 24 significantly change these requirements. For the present, a dedicated computer is required within the Primary server to compress the audio stream. The decompression process takes place on end Users' computers and preferably would use only a portion of the computers' computational requirements, ~5 allowing the computers to be used for other tasks while they are processing the audio stream.
It is important to appreciate that 'the compression and decompression techniques employed by the present invention are not critical to the overall operation of the 30 system and the advantages obtained therefrom could be obtained with other compression methodologies.
Advantageously, the identity of the compression technique used can be encoded into the audio stream in the packet header. This makes it possible to identify to the receiver s5 the nature of the decompression algorithm to use~ and thereby make it possible for the computer within the F~rimary Server _ g ._ to select an optimum compression algorithm defending on the nature of the audio stream to be compressed.
The remainder of the distribution architecture comprises the multilevel hierarchy of data transmission originating at the Primary Server 20 and terminat3.ng at the Users 40 as shown',in Figure.3. In the preferred embodiment, the network is the global connected Internet. 7Ct can also include private networks that are~connected to the Internet and it could be implemented on any packet switched.network, 1,0 cable=modem-based or satellite-based cable system~~ It is possible that certain links within the overall system, for example, the link between the Primary Server and the first level of Med3.a Servers, are private data links that carry ~only.data associated with this.system. This could also be true of other data transmission_paths in the distribution architecture. . The User receiving ;the information preferably can be anyone who has access to the Internet with~sufficient bandwidth to receive the resulting audio data.
It should be appreciated that the distribution 2~ architecture of ahe present invei~tio~ provides for scalability. Using such a structure~ any ~ number of tlse~~
and as widely distributed as necessary, can be accommodated.
In the preferred embodiment, the fan-out at each level.o~~.
Media Server cgiven~the state of technology today) is on the order of ten,~but.the same structure could be applie8v.with other fan-outs. The location and fan~out of the Media.
Servers is chosen to minimize overall iietwork~bandwidth consumed.
The -flow of information fro~i Primary Server ~0 through network to User ~0 is based can the delivery of av continuous sequence~of individual pieces of information, or packets. Thus the distribution architecture implements a form of multicast packet delivery to a group. The group in this case is the set of all Users who are listening to a given channel at a given time. Group membership is dynamic;
users can start and stop listening to a channel at any time.
~ g Multicasting can be implemented in a variety of ways, any or, all of which can be used~in the present invention. Tn the preferred embodiment, .the Media Servers receive unicast packet stieams and they then duplicate thess streams into mope unicast streams to ~ther Media Servers that are in the membership group for that stream. The lowest level Media Servers use hardware broadcast, multicast and/or unicast to reach all Users served by that~Media Server.
gp If the Media Server is directly connected.t~ the same physical network as the. User, hardware broadcast or multicast can be used to transmit the packet.strea~a,to ali Users listening at that time on that network. In this case the Media Servers can translate the inco~aing packets into t5 broadcast or multicast packets for transmission on the local network:, Only a single packet is transmitted at-a=time.on the local network..and any computer directly connected t~ the local network can receive that packet. Hardware multicast'is built into most networks and it is lower iw overall overhead Z0 than hardware broadcast since.computers riot interested in a transmission do not have to process the~packets. In the case that a Media Server is serving a tTser who is not on the same physical network,va unicast transmission is used to reach that User, which requires a.separate packet transmission for 25 each User so connected. In. the preferred embpdiment, the.
assignment of Users to Media Servers is done using cbntrol transactions among the User ~f; Control Servers 5~, and Administration Server 60. This system will be described~more fully in the following section.
3o Multicasting can also be implemented within t3ie~
Internet at the IP level,usxng~Il? class D addresses and the 7~GMP group control protocol. Fig. 4 illustrates how the multilevel hierarchical distribution architecture would operate using IP multicast delivery. Under this~system, a 35 packet is transmitted Wi_th~a multicast address for a destination and each router,maintains group membership lists for each interface that it is connected 'to and will forward packets across the Internet to other routers such that all Users within the global group eventually receive a copy of the,packet. Unless and until all rnuters within the Internet understand multicasting in this way, it is necessary to supplement it with ~P,tunneling in which multicast packets are encapsulated in unicast.packets and xouted by unicast routers to multicast routers. The present invention can and will be able to take advantage of IP multicasting as it becomes widely available. Each chanaiiel of information would io be given its own class D address and the Media Server would then simply transmit packet-s.using the appropriate IP
destination address. In this case no Media Servers would-be used as this function would be accoanplished by the routers in.' use to stare and forward other IP packets.
Thus it can be appreciated that the implementation . of the multicast delivery structure can be implemented using.
a~combination of IP unicast, IP multicast and hardware multicast or any other system that provides for distributed delivery of infor.°matio=a .to a specif;:c group of~ destinations.
It is expected that special relationships with Internet . providers will be established so~that delivery of. the audio steams can take place with~a~guaranteed.bandwidth and iw the most efficient way possible.
In the preferred embodiment, packets c~f information for distribution use the UDP protocol under IP rather. than the TCP protocol. TCP provides for reliable stream delivery but at the cost~of retransmission and delays. For real-time information, it is usually more appropriate to use.ilDP since the information is time critical and. low latency is more important that reliability. Since TCP is a point-to-point protocol, it is incompatible with IP multxcasting. However TCP could be used on the IP unicast links between Media Servers that are.expected to have very ~.ow packet loss.. In order to handle out. of order;"lost, duplicate and corrupted packets, the ilDP packets are serialized~' w In the preferred embodiment the size of the~audio packets.being transmitted is variable and can change on a packet by packet'basis. It is expected 'that when using compression schemes that have a fixed bit rate, .such as ADPCM, all packets for that stream-would be the same size.
Alternatively when:using a variable.bit rate compressiow algorithm, it ~.s expected that packet,si~e would wary so°as~
to establish approximately the same amount of time for each sample.v. For example, ~.f each packet corresponds.to a 20 millisecond segment of speech, this could. correspond to.100 bites duriaig one time period and 200 .bytes during another.
to Additionally, the Media Server'may choose to dynamically vary the packet size to accommodate~changes i~a network conditions.
Since the resulting playback of audio information is sensitive to packet loss and network congestion, software .running on the various computers that, make up this system i5 monitors the ongoing situation and adapt to it in the best possible way.: This may, involve using different Media Servers and/or lowering the data rate to the User. For example, similar to analog dynamic s3gnal'quality negotiation present in many analog radio receivers,~the User.software may request 2o a lower bitrate until the~situation is improved...Also, note that .the audio information being delivered to the User its preferably . ,inter~.eaved , so that, a contiguous segment ~of the audio stream is distributed for trarismiseion ov~.r.several ~.
packets. As.a result, the loss of one packet'is spread out 25 over multiple audio~swmples and causes minimal degradation in audio.. Advantageously, a small degree of redundancy may be incoz~porated~ within ~ the audio strew to i'urther guard against"
packet loss. .
Preferably, there are two citrate options available 3o to the User fog audio delivery:,.. These are approximately 2oKbps for standard audio and approximately 56Rbps~for high quality audio. Thus, a 28.8Rbps modem connection over"an analog phone line is sufficient to listen to standard audio .
broadcasts. To listen t~o high quality audio, an ISDN .
35 connection to the Internet is required, or some .other connection with greater than 56Rbps bandwidth. It should be appreciated that higher bandwidths are currently~becoming w 12 available to end Users. In particular the use of cable modems and residential fiber networks are enhancing the bandwidths available to Users and thus making broadcasts of higher bitrates more practical.
In addition to the content of the audio channel being delivered, it is also possible to deliver out of band of side-bar information such as graphics, images and text.
This side-bar information is synchronized with the audio channel. This may only involve small increases in bandwidth requirements, such as 1-2Kbps. For example a music program could deliver images of an album cover, the text of song lyrics, or URLs for use by a Web browser. The User can preferably choose to have the side-bar information show up automatically or be hidden. It is also possible to incorporate two-way interactioninto the system, such that for example Users can participate in a global chat session during the audio broadcast. These and other details are explained in more detail below under the description of the User interface.
The delivery of paid commercial advertising information is an important aspect of the present invention.
Advertising may be incorporated into the audio stream within the Network Control Center as described above. It may also be incorporated into the audio stream at the User level, or at some intermediate point in the distribution architecture.
In addition, the side-bar information discussed above can also include advertising content. Fig. 5 illustrates the provision to the User of two separate streams 32, 34 of packets, one of which may be used for advertising. In this case the insertion of the stream of commercial advertising into the non-commercial stream occurs on the User's computer. Fig. 5 also illustrates packet stream 36, which identifies the User to the system. This enables the system to monitor which Users are listening to which channels and also allows the system to vary, for example, the advertising content delivered to a User.

One advantage of this alternative is to allow . targeted commercial delivery based on the individual User.
That is, an individual User would receive the main audio feed plus a particular advertising stream unique too his demographic group. Note that the advertising stream typically is lower in overall bitrate and generally does not require real-time delivery, thus lowering the overall load on the network. For example, the advertising stream could be delivered to the User in advance of the regular programming, stored in a buffer in the User s computer and inserted into the stream of regular programming upon receipt of a cueing signal embedded in the stream of regular programming~ Thus, a substantial number of targeted groups, perhaps 10 or 100 or even more could be accommodated without an impractical increase in network load.
II. Control Architecture The control architecture described in this section is responsible for managing and administering the Users who are receiving the information being delivered by the distribution architecture described in t:he previous section.
The control architecture handles new User registration, User login, the starting and stopping of audio streams and the monitoring of ongoing transmissions. The control architecture is scalable just as is the distribution architecture so that any number of Users can be managed.
This section describes the control. protocol, which consists of the format and sequence of control messages that are exchanged among Users, Control Servers, Media Servers, 3~ Primary Servers and the Administration server. These messages are in the form of ~bjects, which have specifis data formats. Objects are exchanged preferably using the TGP
protocol although other options are possible. Below we describe the sequence of objects passed among the various computers and detail the internal structure of each object.

The major objects used in the present embodiment ~f . the invention are set forth in Table 1. For each object, Table 1. provides a brief description of its tEunction, identification of the names of the fields in the object, their types and a brief description of irheir function.
Channel Activation Object T1~,13 .~
Contains information used for charmed activatio~~zldeactivatian. It is sent s o to li~edia and Primary Servers to tell them to carry or stop carrying a specific channel. Media Servers get the channel from another server in the system hierarchy and Primary Servers get and encode the feed from the actual input source.
Field Name Field ~'ype itemar&s ZS Token Security Token Object Moniker Moniker Object unique channel identifier activate lnt action flag (activateldeactivate) CompressType Int type of compression to use Host Host Object host carrying the channel Channel Guide Object Contains analytical and descriptive information for an item requested that is uniquely identr; fled by a moniker. It is usually the reply to a Channel Guide Request object.
Field Name lE~eld 'Type Remarks Token Security Token Object Type Int type of content Result the content daea itself Channel Guide Request Object Conveys a request for analytical and descriptive information about an s o item uniquely idenh~ed by the contained moniker. The reply is in the form of a Channel Guide object.
Field Name held Type Remarks Token Security Token Object inherited from base class Type Int type of content Monaker Moniker Object unique identifier ~ 1~ _ Table 1 (continued) -Host Object Encapsulates the attributes of a networked computer related to the operation or services it offers or requests.
Field Name Meld Type Remar%s Token Security Token ~bject HostName String computer name and domain PortNumber Int port number for service DisplayNume String descriptive computer name s o gin Information Object E~«apsulates the name and password by which a fleet is known to the sysyem.
Field Naare Field Type Rettaarks Token Security Token ~bject I ogin String User's system login name Password String Use:r's system password (possibly encrypted) Medda Control Interface (MCI) Request Object ~ Encapsulates a multimedia control command, such as play and stop, and any extra information that may be necessary to perform the requested service.
Field Name Field Type Rennarks Token Security 'Token ~bject 2 5 C~mmand Int multimedia command String String cotr~mand-specific extra info Moniker Object A moniker encapsulates the name of an object or process with the intelligence necessary to work with that rrtame. In other words, it 3 o pr~yides naming and' binding services. 1'he Moniker Object is used in the system f~r unique identification of various components, parts or -- features, such as a channel, a directory, or ~a computer list.
Field Name Field Type Remarks Token Security Token ~bject 3 r ID String unique string identifier DisplayName String User-readable name _ 1~ _ T'a6le 1 (continued) Ping Object Ping is the name given to the "Are-You-Alive?" operation useful in determining if a specific computer is up and running. This object is 5 used in the system when a server has to be queried for its operational status. dt can also provide timing informatdon jbr statistical purposes and quality of service evaluations, Field Name Field Type Remarks Token Security Token Object Date Date system date 1 ~ fiime Time system time Protocol List Object encapsulates a general purpose collecdion object.
Field Name Field Type Remarks Token Security Token Object Type Int type of object list Idesult Message Object 2 o Acts as the acknowledgment for a requested service successfully carried that out or reports errors that occur in the system during a clientlserver transaction.
Field Name Field Type Remarks Token Security Token Object 2 5 bode lnt result code Message String message corresponding to code Security Token Object Contains the authorization key for a transaction. The key must be validated before any service is performed"
Field Name Field Type Ren'arks ID String authorisation keyltransaction ID.

Table d (continued) Server Activation Object Contains information used in the server activationldeactivation process.
Used for announcement as well as command purposes (e.g., a server can n~tt; fy the administration database that is now activated or a server can be instructed to manage someone else).
Field Name Field Type Remarks Token Security Token Object Active Int action flag (activate/da:.activate) Manage Int control flag (managelassociate) Type Int server type Host Host Object host to be controlled ,Server List ~tequest Object Encapsulates a request for a list of available server resources for an identt~ed service (e.g., a request for a list of Control Servers for a specified channel).
Field Name Field Type Remarks Token Security Token Object Type Int type of service Moniker Moniker Object contentlchannel unique identifier Host Host Object local host information Statistics Object Contains system-related information that a:an be used by load balancing algorithms and for statistical purposes.
2 5 Field Name Field Type Remarks Token Security Token Object Load Int load on the system Threads Int number of threads running Users Int number of iJsers being Uptime Int serviced 3 0 NumberManaged Int amount of time running NumberAssociated Int number of managed servers number of associated servers gfl _ Statistics Request Object Encapsulates a request for system-related information that can be used by load balancing algorithms and statistical purposes.
Field Name Field Type Remarks Token Security Token Object Load Int request flag (onlof~

Threads Int request flag (onloff) Users Int request flag (on/off~

Uptime Int request flag (on/of~

NumberManaged Int request flag (on/off) g ~ NumberAssociaeed Int request flag (on/off~

User Object Users and Servers use this object to register themsedves with the administration database. They provide the information for subsequent logins (name, password] and other system-related info. The end Users ~5 provide personal, demographic, and system-related information.
Field Name Field ~'ype Remarks Token Security 'Token Object Login Login Information login information(name, Object password) FirstName String User's first name LastName String User's last name TFtle String User's job title Company String User's employer Addressl String User's home street address Address2 String User's address extra City String city, village State String state, province or foreign country ZipCode String zip or postal code Age String User's age 2 5 Gender String User's gender PhoneNumber String telephone number FarNumber String fax number En:.a; l String email address Deanographlcs Dictionary market-targeting extra User info Sysremdnfo Dictionary system-related information 3~

Table ~ (continued) Version Object All components of the system use this object to report their versioning information to the party they transact with in order to use a protocol s they both understand. They are also given the chance to update themselves if a newer version exists.
Field Name Fyetd Type Remarks T~ken Security Token Object Major Int major protocol version number Minor Int minor protocol version number 1~ Type Int sender type Client Version client version information Unlike traditional protocols based on state computers, the control protocol of the present invention is a light-weight, stateless protocol comprising simple sequences 15 of objects. It is light-weight in that in most sequences only two objects are involved ire the transaction and after a sequence is completed the connectian can be reused. Tt is also stateless in that the server maintains no information about the client. Every transaction is I;xandled independently 20 of the previous ones. States exist in the lower levels, for example within the TCP layer, to express logical states of a network connection but they are not actually part of the control protocol.
in the preferred embodiment, the software running 25 on the Control Servers, Media Servers and Primary Servers is programmed for Windows NT and UNIX environment using the OLE
environment. In addition, COM interfaces are used between components. The Rogue Wave system is used to transfer objects between the applications running on the various 30 Computers. The software running on the User computer is preferably programmed for a Windows 32-bit environment, so it will run on a Windows 95 or Windows NT CC)mplitE:r.
Alternatively, Macintosh and UNIX environments can be accommodated by other User software, 35 The basic process of a control transaction consists of a version sequence followed by one or more protoco.~
~ 20 -sequences. The version sequence starts after,the .computer ~~-initiating the transaction, the client, has established a connection with the computer completing the transaction, the server. The client sends a Version Object (defined in Table 1) and in response the server then sends back its own Version Object. This version sequence is used so that both client and server are aware of the version numbers of the software they are using. If a version number is older than expected, either client or server can choose to conform to the previous version or abort the transaction, depending on its needs and capabilities. If a version number as newer than expected, in most cases the current transaction can be completed since the software systems are designed to be fully backward compatible with previous versions. Additionally, in the case that the server of the transaction is tree Administration Server, the client receives information about what the latest version number is and thus the client can be informed that a software update is needed. The process of handling automatic updating of User software is described more fully below.
After the version sequence, one or more protocol sequences occur in which other objects are exchanged between client and server. When a particular protocol sequence is completed, another independent protocol sequence can be serviced. The protocol sequences that are part of the Z5 control architecture of the present invention are summarized in Table 2 and described below in conjunction with Figures 6-2~.

~°Al~~a~' St~nary o~ Protocol 8e~a~enc~s tro . eq~~ . : llettt Serveir atn O ~eCt~ : xC ang User RegistrationUser Administration Version Object and Login User Object (see Fig. Channel Guide Object 6) User Login User Administration Version Object (sue Fig. L.agin Information Object 7) Channel Guide Object Channel PlayUser Administration Version Object (see Figs Server List Object 8a, 8B, 8C) Control Version Object Server List Object Media 'Version Object MCI Objects -Ping Objets (TCP connection stays open) Token ValidationControl or Administration'Version Object or ~

(see Figs. Media or Control Security 'Token Object 9A, 9B) Primary Server Media or Administration Version Object 2 RegistrationControl I,7ser Object 5 and ~gm Server Acrivation Object (see Fig.
10) Server LoginMedia or Administration Version Object (see Fig. Control L,ogin Object 11) Server Activation Object Conerol ServerAdministration Control 'Tension Object Activation Server Activation Object (see Fig.
If lz) II

_ 2~ _ ::.., . . .:..::..::::::::.,.,;:..:,..;; , ......, - ._.
tr . en~_...-::~:: ... . ...,...-::::.:::::... "...................
::.. . . :.....:,.
:.-..... .::: . , . .:.:::::.".
-.. : . w , , teFFt..............".,..:.: ::: :..
,:y ~...;..;,"... :... _..:.,.....::::.; . - ":
, ::::.:: :::::.. .:::::..:::.;;,.;':'~;::::::..... . aim : ...::::.:::"
,:::. on ..: ,:,.::.>::.:.::.~::.;.:';::;.....-....:..:.
O .: .. .:.:CI,- .-::::.:.::.:.::.,....._.......... , ~~~
. :... ,.::,,:::::. e.... ..,. . .. .
....: :,,:: ..5..:.:_:._...... .. ~~..... ~, . . .
":;; _.: ..." . . . , ... . ..... ...,.
.....:.n~ ,,\ ........., ..... . ,.... . .....
,..~;,~,: ~:: ::v:::,:: ..: ..:._::.. .........:,r; : .~..:.,::...
.":::: :: ........, ,,. " ".............. ,~:...... ..,..,.n .. ..... ....,. ,..,........... ., ........ ..
- ~ ... >" , :...; " .. .. .....,: , .,.. .....:.
...... ........."..:.::...v; ;\..,.,::.:::.::.:.......,.,...........
..,: . .._. .....,:..n,", Media ServerControl Media 'Version Object Activation Server Activation Object (see Fig. Ping Objects 13) (TCP connection stays open) Control ChannelAdministration Control Version Objet Activation Channel Activation Object (see Fig.
14) M~ia ChannelControl Media (open TCP connection) Activation Channel Activation Objects (see Fig.
15) DistributionMedia Media or Version Object Activation Primary MCI Objects (~ Fig. 16) OPEN/PLAY/STOP/CLOSE

Ping Objects (TCP connection stays open}

Statistics Administration Control Version Object Request or (sea Fig. Media Statistics Object 17}

The User registration and login sequences are the processes by which a new User registers with the system, logs in and retrieves programming information~ The channel play sequence takes place when a User asks to listen to a particular channel. The token validation sequence is used to verify that a computer requesting a service is authorized to do so. The Server registration, login and activation sequences are used by Control and Media Servers when they become active. The Control Server and IH(edia Server activation sequences are used to manage the Control and Media Servers. The control channel, media channel and distribution activation sequences are used to cause a channel to be distributed to a Media Server. Finally, the statistics request is used for administrative purposes.

Fig. ~ illustrates the User registration and logii, sequence in more detail. This seguence,takes place after the User has installed the User software on his/her computer.. It is expected.that the User will,download the software from the Internet and then invoke it, which in the preferred embodiment will use the Windows Wizard interface: This will guide the.
User through the installation process including filling out the registration form, which we wil3 describe more fully in the next section. After the User has selected a name and ~.0 password and selected the option.to register, the User ~. .
computer opens a TC1? c~nnection to the A~tministration Server.
Advantageously, the full domain name of-°the Administration Server is. embedded into the User software, although it could be discovered in other ways.' The User ahd Administration .
l5 Server then exchange version objectss with the Administration .
Server as described above. If tree version numbers vieet expectations, the User sends a Ueer Object to the Administration Server., The format of.the User Object is shown 'in Table 3. Once the'Administration Server receives ~0 the User object, it verifies that..the information is filled in properly and that the selectedUser. naive , is unique:: ~ If the User Object is invalid for any reason, the Administration Server returas:a Result Message object with a.code indicating the reason. The format of the Result Message Object is shown 25 in Table 1. If the User information is valid, the .
Administration,Server updates the global database of User names and passwords and then generates a security token f~r that User. This security token is then returned to the ~Tser.
ixr a Result Message Object.
30 .Upon receiving the Result Message Object, the User saves the security token for future use. .This.token is a~a identifier that allows the User.to request services from the Administration Server and. other computers within tire overall' system. The security-token is hot saved permanently or 35 registered on the-User computer. Na~mally, the User software then immediately sends a claannel.Guide Request Object to the Administration Server and a Channel Guide Object is returned:.
~ 24 -The format of these objects is also shown in Table. 1. Note-that in principle, this.is a separate transaction and could take place in a separate TCP connection to the Administration Server. In particular, once the User has registered and logged in, he/she can request the Channel Guide ~b~ect again since it may have been updated since the previous.re~uest.~
~At this point. the TCh~ connection to the ~rdministration'~;server is closed.
The process of User registration only net to take io place,once.for each User. However~anyone can re-register at any time, even after the software, has ~beein installed. Iti particular, it is expected that if multiple persons use a computer, each-person will register end obtain his/her own User name and password.. If the registration process is not :5 completed successfully, the User software saves ttie registration.i~aformation and asks the User if he/she .would like to try again the next time~the software is inv~oked.~
since the security~token is not permanently.sav~d by the~User software, it is lost when thd Uses software .is 2o closed, and the security token must''again be r~trieved fry the Administration Server the next time the User wants to use the system.. . T~iis~ process is the purpose of the .login sequence illustrated in Fig. .7. This sec~uen~'e is used if a .
User has already registered and needs only to retrieve~a 25 valid secu~~.ty,token. In this case.~the sequence consists of the Oser~s sending a T.ogin Information object to the Administration Server. The~Administration Server than queries the User database to validate the login rr ~ acrd password, if the loqin name and password are:corrwct, than a 3o security token~~is returned to the User. ~lormally the receipt of the security token will ianmediately be follot~ by a channel info~nation request sequence, dust ,as in the registration sequence described previously.
The control sequence that ioakes place when a.User 33 initiates a channel play operation i~s illustrated in Figs.
8A, 8B and 8C. (First the User software" requests a Control server List from the Administration Server. Dote that the Server List Request Object, illustrated in Table l.contains~~a . channel identifier. The Administration. Server generates a sorted list ~~f Control Servers based on overall system load and the location of the User on the network and returns this list to the User using a Protocol List Object. Once the Control Server List is returned to the User, the Administration Server is no longer needed and the TCP
connection is closed.
The User software then searches the list of Control 30 Servers and opens a TCP connection to the first host listed.
If that host computer does not respond, then the next Control Server on the list is tested and so forth in succession.
Upon obtaining a response from a Control Server, the User software uses a Server List Request Object to requests a Media Server List from the Control Server. :Cf the Control server is too busy to service the User, it returns a Result Message Object so indicating and the User software tries the next Control Server on the list. However, in the likely scenario that the Control Server is able to handle the User's request, a sorted list of Media Servers is generated and returned to the User computer using a Protocol List Object.
The TCP connection to the Control Server is then closed by the User software.
At this point the User software initiates a TCP
connection to the first Media Server on the list provided by the Control Server. As in the previous case, it attempts to connect to the first host on the list and if unsuccessful tries the next hosts in succession. Once the Version Objects are exchanged, the User software sends an MCI Request Object to the Media Server. An MCI Request Object can be used for four basic commands: OPEN, PLAY, STOP and CLOSE. The User software must first send an OPEN command for the desired channel. If the returned Result Message Object indicates success, the User software then sends a PLAY command.
When the Media Server receives a valid PLAY
command, it initiates the delivery of audio information to the User as described in the previous section, Dote that this could be in the form of broadcast, mul~icast or unicast packets to a specific UBP port. The TCp connection through which the MCI Request Objects were sent stays open during the audio play operation. In addition, Ping Objects are sent to the User on a periodic basis to verify that the computer is still working and active. When the User software receives a Ping object, it simply returns it. The Media Server uses the Ping Objects to measure round trip time and also to determine when a User's computer has terminated abnormally. In that case the audio stream is terminated.
In the case of normal termination of the audio stream, the User makes an explicit selection to stop and this causes a STOP command to be sent to the Media Server in an MCI Request Object. The Media Server then terminates the audio stream to that User. When the User closes the application software or selects another channel to play, the User software will send a CLOSE command to the Media Server in an MCI Request Object and the TCP connection is closed.
The initiation of the audio stream by the Meda_a Server causes a log entry to be generated and sent to the Administration Server. This information is important so that the Administration Server can update its database to indicate which Users are listening to which channels. The security token is used to identify the User initiating the audio stream. Additionally, when the audio stream is terminated to any User, another iog message is generated and sent to the Administration Server.
Fig. 9A illustrates the process by which security tokens are validated.. The Administration Server is the only server that can validate a security token. Thus, when a User requests services from a Control Server or from a Media Server, that server must go back to the Administration Server with a token validation sequence. However, Control Servers and Media Servers are allowed to cache validations of security tokens so that they do not have to validate tokens repeatedly once they have validated it the first tame. In the case where a Media Server receives a request, the token will be va7.idated with the Control Server that is managing.
that Media Server. F'ig. 9S identifies the various token validation scenarios.
Fig. 1~ illustrates the process by which a new server is registered. This process .is similar to.new User registration. zt.is expected, howwer, that the server installation will be through a Web interface rather~than a-Wizasd. The Administration Server, upon receiving a ~Tser .
Obj ect ~roin a Media Server or .Control server, validates the lo.User~name and password and generates a security token just as in the case of User~regist~ation. Normally the Server then immediately sends back a server Activation object indicating that it is ready to be used as a system resource. ~nce this process has_bee~n.completed, the TCP connection to the a5 Administration server is closed.
If a Media Servsr or Cont~°ol Server that has sent a Server Activation Object to the Administration Server becomes inactive, it will send another Server Activation object indicating this condition. In the ease of a Media Server, 2o dais object is sent to the managing Control Serve. ~In~the~
case of a Control Server, this object sent to: the Administration Server. As in the case of User;registration, Media Server and Control Server regi.~tration needs only~take place once per ~ computer. However, if the computer i~. ~ ~ .
25 restarted, the server must login and again retrieve a security token. This is the server 1~gin and activation sequence shown in Figure ih.
once a Control Server has indicated to the Administration Server that it is ready, the Administration 30 server can activate that Control Server'by sending the .»~~, Control Server a Server Activation Object ae illustrated in Fig. 12. This is a separate transaction and is used t~ tell the control Server which Media Servers it is supposed to manage. Recall that a Control Server and a numberlof Media 35 servers form a cluster-of Media Servers. The single control Server that manages that cluster must be given a list of host computers corresponding to the Media servers in that cluster.
-° 28 -The process by which a Control Server activates the Media Servers.that it manages is~illustrated in Fig, l3-. The Control Serves sends a Server Activation Object to'the Media . server indicating that it is responsible fer channel management. This TCP connection between the Contr~1 Server and, the Media Server stays open during the time that both servers are active. The Control Server periodically sends Ping objects to the Media Server.across this open TCP
connection to verify~that the Media server is~still_running.
i0 ~ Fig.' 9.~ illustrates the process by ~ which a ~ given channel is activated by the Administration Server. The Administratio~a Server opens a connection to a Control Server that its wishes to have carry a given channel and provide a Channel Activation Object. This object indicates to the i5 Control. Server Which Media or Primary Server the Control Server should direct its Mecia Servers to get the feed from.
At this point the Control Server is said to ba carrying that channel and it will..be a valid host on a list of Control Servers requested by a Chaiziiel Play sequence.
a0 Fig. 15 illustrates what. happens when a C~ntrol Server needs to provide a channel. First it sends a~Channel Activation~bject to one of the Media. Servers that it manages acrciss the,operl TCCP connection~described previously. This .
object indicates to the Media Server that it should start 25 receiving the channel identified and from where it should receive it.
~. In Figs. 16A and 1SH depict how the Media serer requests distribution of an audio channel from another_Media server or from a Primary server. Tb.is sequence is much the 30 same as that in which a ilser requests the distribution of audio information..~rom a Media ~Se~rver. ' Note that a Media Server receives a siaigle incoming stream for each channel that it is carrying and then redistributes this stream to all Users~or other Media Servers that request it.
35 Finally, Fig. IT illustrates the statistics request sequence. This secsuence is used by the Ad~ainistration Server to gather information. from the Media Servers and Control Servers in order to manage the overall system. It can use this information to detect failures and to balance load as the dynamic.conditions change. l~s indicated above, it can also~use this information to monitor which:Users are listening ~to ~ahicli channel' or whether Users stop listening 't~
a channel,at any time, such.as during the p3~ay of a particular song. 'It can also use this information to control the. advertising. content that is downloaded to'a particular User in advance of receipt of regular audio programming io and/or monitor, the delivery_of advertising to the Users.
The cantrol architecture described in this section is scalable to handle any number of Users. Note.that the User registration process only happens. once for each subscriber and the 3.ogin process~only happens once per i5 sessions These interactions, which require the Administration Server,~are eXpecte~d.to constitute a.very small ' ' percentage:of the overall system,bandwidth. If the Administration Server. were to become a bottleneck, however, ~it would ~be possible to duplicate it~and to have the database 20 it maintains distrib~xted and automatically updated to .
guarantee cansisten~r.. ~ . .
. The Control Servers are dvstributed throughout the ' network and can handle the lower level ~i~rteractions -with the .Users and the Media Servers. A single Control :Server,can 25 handle preferably on the order of ten Media Servers up t~
several hundred t3sers. The bitrate among the Users, the Control Servers and the Media-Servers is expected to be'smahl.
in comparison to the audio transmission bitrate. The Ping objects~normally only involve the User and the ne~x°est Media 3o Server. They are also low in overhead since their are small and only get transmitted infrequently.
III. User Interface The User interface is provided by. the client application 35 runni.rig ~on an individual computer .and its associated graphical interface. In the preferred embodiment the Usex interface is available for 32-hit Windows (95.and NT), Macintosh anal UNIX platforms. Preferably anyone on the Internet can freely download a copy of the client software and install it in their computer.
Figure 18 illustrates the main User screen in the preferred embodiment. The screen is composed of three sections: channel guide (upper left frame), program guide (upper right frame), and multimedia frame (lower half of screen). The channel guide lists, as a tree hierarchy, the channels that are available from the system. The User l0 selects a channel from the list of those displayed on the channel guide. The program guide provides information pertaining to the channel selected. This information can be a detailed schedule of the programming that has played or will be glaying on the channel selected. Additionally, other ~5 relevant informatiora will be displayed in this frame, for example, a notice regarding an upcoming special event on another channel. True multimedia frame provides an integrated web browser that displays information via a series of tabbed sections.
2A The information. contained in the channel guide, program guide, and the tabs of the multimedia frame is dynamically transmitted to the client. for example, if a new channel begins operation, the client application can immediately display it as being available. Furthermore, the tabs 25 displayed can be specifically relevant depending on what song is playing. For example, tabs displaying the album cover, information on the artist, song lyrics, tour dates can be displayed. Additionally, as shown in the example in figure 18, a tab caz be available allowing the User to place an 30 order for the CD or allowing the User to participate in a chat session related to the channel.
Figure ~.9 illustrates the key pull-down menus available in the main User screen in the preferred embodiment. Table 3 provides a description of each of the functions available 35 through the pull down menus, as shown in figure 19.
_ 31 As~will be apparent to those skilled in the art, w numerous modifications may be made.within the spirit arid scope ef the invention.
. ~ ~a~~~ ~ .
pulL~-Down Menu Functic~n~
Menu MeaWBub.-Cho ce besc=~.ptaon Choice , ga a Log~rt A
ows the User o og to .
__ _ _..

the- system.

i0 y Logout A ows the User o ogou from the system. .' Register Hsings up a a og so a the User c:an register with .

the syste~a for the (first time:

close Minimizes t a screen..

Ed t copy A ows a User to cogy a selection on ~to ~t~is clipboard.

Proper ies A ows a user o se various properties.

hudie P ay Begins playing a se ec a channel. ."' ~ s op stops p ay ng. a se ecte .
"' 2 , channel.

Mute "'~ stops a p ayang o au o "

view Too Bar W sp ay or a. a a too (providing'access to pull-down menu functions). .
--status Bar -'D~.sp~.ay or ha a a s atus bar. normally situatedl~at 25 ~ botton of the screen. ' Web sar Dasp ay or hi a a too section that provides access t~ the web browser functions.

Help ~ielp Topics -Bsings up a s o avai a a online help topics.

Abou .... Displavys summary inforcnatioa 30 ~ regarding this application, such as version number, copy-right information, arid so on.

..

- sa -

Claims (56)

What is claimed is:

1. A method for monitoring the forwarding of real-time information to at least one user having access to a communications network comprising:
generating delivery-commencement indications of real-time information forwarded to the user by means of the communications network, wherein the real-time information comprises a plurality of packets forwarded over the communications network to the user, verifying the operational status of the user's access to the communications network during delivery of the real-time information, and generating delivery-termination indications of the real-time information forwarded to the user.

2. The method of claim 1 wherein the verifying step indicates abnormal termination of the user's access to the communications network, and wherein the generated delivery-termination indications then also comprise indications of the abnormal termination.

3. The method of claim 1 further comprising updating a database with information provided by the delivery-commencement and the delivery-termination indications.

4. The method of claim 1 wherein the delivery-commencement indications and delivery-termination indications further comprise time information.

5. The method of claim 1 wherein the operational status comprises an active/working status.

6. The method of claim 1 wherein the step of verifying further comprises forwarding over the communications network messages concerning the operational status of the user's access to the communications network.

7. The method of claim 6 wherein the messages concerning the operational status of the user's access to the communications network are initiated by the user.

8. The method of claim 6 wherein the messages concerning the operational status of the user's access to the communications network are received by the user and responded to by the user.

9. The method of claim 6 wherein the communications network further comprises at least one server computer, and wherein the messages concerning the operational status of the user access to the communications network are initiated by the server computer.

10. The method of claim 1 wherein the indications of delivery-commencement and of delivery-termination are stored on the server computer.

11. The method of claim 1 wherein the delivery-commencement indications and the delivery-termination indications are stored at the user.

12. The method of claim 11 wherein the delivery-commencement indications and the delivery-termination indications that are stored at the user are later forwarded over the communications network to the server computer.

13. The method of claim 1 further comprising a step of determining the total delivery time of the real-time information to the user from the delivery-commencement and the delivery-termination indications.

14. The method of claim 13 further comprising a step of determining the content of the real-time information delivered during the total delivery time.

15. The method of claim 13 wherein the total delivery time is determined as the total elapsed time between delivery-commencement and delivery-termination indications during which the user's access to the communications network was also verified to be in an active/working operational status.

16. The method of claim 1 wherein the real-time information comprises audio information, or video information, or advertising information.

17. The method of claim 1 further comprising generating indications of the content of the real-time information.

18. The method of claim 1 wherein an identifier is provided for the user.

19. The method of claim 18 wherein commencement and termination indications are associated with the identifier.

20. The method of claim 1 wherein the communications network includes the Internet.

21. The method of claim 1 wherein the communications network includes a satellite network.

22. The method of claim 1 wherein the communications network includes a cable TV network.

23. The method of claim 1 wherein the communications network includes a private data network.

24. A method for monitoring the forwarding of real-time information to at least one user having access to a communications network comprising:
generating delivery-commencement indications of real-time information to the user, wherein the real-time information comprises a plurality of packets comprising audio information, or video information and is forwarded over the communications network to the user, and wherein the delivery-commencement indications further comprise time information, verifying the operational status of the user's access to the communications network during delivery of the real-time information, wherein the operational status includes abnormal termination, generating delivery-termination indications of the real-time information to the user, wherein the delivery-termination indications further comprise time information and indications of any abnormal termination, and updating a database with information provided by the delivery-commencement and the delivery-termination indications.

25. The method of claim 24 wherein the step of verifying further comprises forwarding over the communications network messages concerning the operational status of the user's access to the communications network.

26. The method of claim 24 further comprising a step of determining the total delivery time of the real-time information to the user from the delivery-commencement and the delivery-termination indications.

27. The method of claim 26 wherein the total delivery time is determined as the total elapsed time between delivery-commencement and delivery-termination indications during which the user's access to the communications network was also verified to be in an active/working operational status.

28. The method of claim 24 further comprising generating indications of the content of the real-time information, and wherein the database is updated with information provided by the content indications.

29. A method for forwarding real-time information to one or more users having access to a communications network comprising:
processing one or more streams of audio or visual information into one or more streams of packets for forwarding over the communications network, wherein at least one stream of packets comprises audio or video information, forwarding the digital packets to the users in response to information selection signals received from the users, verifying the operational status of the users access to the communications network during delivery of the real-time information, and updating a database with indications of:
(i) which streams of packets were received by which users, (ii) the time when delivery of each stream to each user commenced, and (iii) the time when delivery of each stream to each user terminated.

30. The method of claim 29 wherein the operational status includes abnormal termination, and wherein the termination time of each data stream further comprises indications of any abnormal termination.

31. The method of claim 29 wherein the step of verifying further comprises forwarding over the communications network to the users messages querying the operational status of the users access to the communications network.

32. The method of claim 29 wherein the messages concerning the operational status of the users' access to the communications network are initiated by the users.

33. The method of claim 32 wherein the messages concerning the operational status of the users' access to the communications network are received by the user and responded to by the user.

34. A method for a user having access to a communications network to obtain real-time information comprising:
forwarding selection signals over the communications network from the user indicating the real-time information desired, receiving one or more streams of packets forwarded to the user over the communications network in response to the selection signals, wherein at least one stream of packets comprises audio or video information, and verifying the operational status of the communications network access during delivery of the real-time information.

35. The method of claim 34 wherein an identifier is provided by the user.

36. The method of claim 34 wherein the step of verifying further comprises responding to messages forwarded to the user concerning the operational status of the user's access to the communications network.

37. The method of claim 34 further comprising the step of forwarding termination signals from the user indicating that termination of the streams of packets is requested.

38. The method of claim 37 wherein the termination signals from the user are voluntary.

39. The method of claim 37 wherein the termination signals from the user are involuntary.

40. A system for a user to obtain real-time information over a communications network comprising a programmable device, wherein the programmable device has access to the communications network, and wherein the programmable device includes user software for causing the programmable device to forward selection signals from the programmable device indicating the real-time information desired, receive one or more streams of packets forwarded to the programmable device in response to the selection signals, wherein at least one stream of packets comprises audio or video information, and verify the operational status of the programmable device during delivery of the real-time information.

41. The system of claim 40 wherein the programmable device comprises a personal computer, or a personal digital assistant, or a telephone, or a mobile phone, or a terminal device, or a television set-top box, or a game console.

42. The system of claim 40 wherein the user software further causes the programmable device to initiate and forward over the communications network messages concerning the programmable device's operational status.

43. The system of claim 40 wherein the user software further causes the programmable device to respond to messages forwarded to the programmable device concerning the programmable device's operational status.

44. The system of claim 40 wherein the user software forwards over the communication network a unique identifier.

45. The system of claim 44 wherein the identifier is provided by the programmable device.

46. The system of claim 44 wherein the identifier is provided by the user software.

47. The system of claim 40 wherein the user software comprises an Internet browser.

48. The system of claim 40 wherein the user software further causes the programmable device to display a channel guide, a program guide, or a multimedia frame.

49. The system of claim 40 wherein the programmable device's operational status comprises its access to the communication network.

50. A software product comprising user software on a computer readable medium for causing a programmable device having access to a communications network to forward selection signals from a user indicating real-time information desired, receive one or more streams of packets forwarded to the user in response to the selection signals, wherein at least one stream of packets comprises audio or video information, and verify the operational status of the programmable device during delivery of the real-time information.

51. The product of claim 50 wherein the user software further causes the programmable device to respond to messages forwarded to the programmable device concerning the programmable device's operational status.

52. The product of claim 50 wherein the user software further causes the programmable device to initiate and forward over the communications network messages concerning the programmable device's operational status.

53. The product of claim 50 wherein the user software forwards over the communication network a unique identifier.

54. The product of claim 50 wherein the user software comprises an Internet browser.

55. The product of claim 50 wherein the user further causes the programmable device to display a channel guide, a program guide, or a multimedia frame.

56. The product of claim 50 wherein the user software is provided in a form that is downloadable over the communications network.