Classifications

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  • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
  • H04L12/00—Data switching networks
  • H04L12/28—Data switching networks characterised by path configuration, e.g. LAN [Local Area Networks] or WAN [Wide Area Networks]
  • H04L12/2801—Broadband local area networks
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  • H04L12/2854—Wide area networks, e.g. public data networks
  • H04L12/2856—Access arrangements, e.g. Internet access
  • H04L12/2858—Access network architectures
  • H04L12/2859—Point-to-point connection between the data network and the subscribers
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  • H04L12/00—Data switching networks
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  • H04L12/2854—Wide area networks, e.g. public data networks
  • H04L12/2856—Access arrangements, e.g. Internet access
  • H04L12/2869—Operational details of access network equipments
  • H04L12/287—Remote access server, e.g. BRAS
  • H04L12/2872—Termination of subscriber connections
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  • H04L12/00—Data switching networks
  • H04L12/28—Data switching networks characterised by path configuration, e.g. LAN [Local Area Networks] or WAN [Wide Area Networks]
  • H04L12/2854—Wide area networks, e.g. public data networks
  • H04L12/2856—Access arrangements, e.g. Internet access
  • H04L12/2869—Operational details of access network equipments
  • H04L12/2898—Subscriber equipments
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  • H04L41/08—Configuration management of networks or network elements
  • H04L41/0803—Configuration setting
  • H04L41/0806—Configuration setting for initial configuration or provisioning, e.g. plug-and-play
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  • H04L41/50—Network service management, e.g. ensuring proper service fulfilment according to agreements
  • H04L41/5003—Managing SLA; Interaction between SLA and QoS
  • H04L41/5019—Ensuring fulfilment of SLA
  • H04L41/5022—Ensuring fulfilment of SLA by giving priorities, e.g. assigning classes of service
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  • H04L47/00—Traffic control in data switching networks
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• • H—ELECTRICITY
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  • H04L47/20—Traffic policing
• • H—ELECTRICITY
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  • H04L47/00—Traffic control in data switching networks
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  • H04L47/24—Traffic characterised by specific attributes, e.g. priority or QoS
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  • H04L47/00—Traffic control in data switching networks
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  • H04L47/2416—Real-time traffic
• • H—ELECTRICITY
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  • H04L47/00—Traffic control in data switching networks
  • H04L47/10—Flow control; Congestion control
  • H04L47/24—Traffic characterised by specific attributes, e.g. priority or QoS
  • H04L47/2441—Traffic characterised by specific attributes, e.g. priority or QoS relying on flow classification, e.g. using integrated services [IntServ]
• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
  • H04L47/00—Traffic control in data switching networks
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  • H04L47/32—Flow control; Congestion control by discarding or delaying data units, e.g. packets or frames
• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
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  • H04L47/00—Traffic control in data switching networks
  • H04L47/70—Admission control; Resource allocation
• • H—ELECTRICITY
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  • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
  • H04L47/00—Traffic control in data switching networks
  • H04L47/70—Admission control; Resource allocation
  • H04L47/72—Admission control; Resource allocation using reservation actions during connection setup
  • H04L47/724—Admission control; Resource allocation using reservation actions during connection setup at intermediate nodes, e.g. resource reservation protocol [RSVP]
• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
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  • H04L47/78—Architectures of resource allocation
  • H04L47/788—Autonomous allocation of resources
• • H—ELECTRICITY
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  • H04L47/70—Admission control; Resource allocation
  • H04L47/80—Actions related to the user profile or the type of traffic
  • H04L47/801—Real time traffic
• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
  • H04L47/00—Traffic control in data switching networks
  • H04L47/70—Admission control; Resource allocation
  • H04L47/80—Actions related to the user profile or the type of traffic
  • H04L47/805—QOS or priority aware
• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
  • H04L47/00—Traffic control in data switching networks
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  • H04L47/82—Miscellaneous aspects
  • H04L47/822—Collecting or measuring resource availability data
• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
  • H04L47/00—Traffic control in data switching networks
  • H04L47/70—Admission control; Resource allocation
  • H04L47/82—Miscellaneous aspects
  • H04L47/829—Topology based
• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
  • H04L61/00—Network arrangements, protocols or services for addressing or naming
  • H04L61/50—Address allocation
  • H04L61/5007—Internet protocol [IP] addresses
• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
  • H04L61/00—Network arrangements, protocols or services for addressing or naming
  • H04L61/50—Address allocation
  • H04L61/5007—Internet protocol [IP] addresses
  • H04L61/5014—Internet protocol [IP] addresses using dynamic host configuration protocol [DHCP] or bootstrap protocol [BOOTP]
• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
  • H04N21/00—Selective content distribution, e.g. interactive television or video on demand [VOD]
  • H04N21/60—Network structure or processes for video distribution between server and client or between remote clients; Control signalling between clients, server and network components; Transmission of management data between server and client, e.g. sending from server to client commands for recording incoming content stream; Communication details between server and client 
  • H04N21/61—Network physical structure; Signal processing
  • H04N21/6106—Network physical structure; Signal processing specially adapted to the downstream path of the transmission network
  • H04N21/6118—Network physical structure; Signal processing specially adapted to the downstream path of the transmission network involving cable transmission, e.g. using a cable modem
• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
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  • H04N21/00—Selective content distribution, e.g. interactive television or video on demand [VOD]
  • H04N21/60—Network structure or processes for video distribution between server and client or between remote clients; Control signalling between clients, server and network components; Transmission of management data between server and client, e.g. sending from server to client commands for recording incoming content stream; Communication details between server and client 
  • H04N21/61—Network physical structure; Signal processing
  • H04N21/6156—Network physical structure; Signal processing specially adapted to the upstream path of the transmission network
  • H04N21/6168—Network physical structure; Signal processing specially adapted to the upstream path of the transmission network involving cable transmission, e.g. using a cable modem
• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
  • H04N7/00—Television systems
  • H04N7/10—Adaptations for transmission by electrical cable
• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
  • H04N7/00—Television systems
  • H04N7/16—Analogue secrecy systems; Analogue subscription systems
  • H04N7/173—Analogue secrecy systems; Analogue subscription systems with two-way working, e.g. subscriber sending a programme selection signal
  • H04N7/17309—Transmission or handling of upstream communications
• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04Q—SELECTING
  • H04Q3/00—Selecting arrangements
  • H04Q3/0016—Arrangements providing connection between exchanges
  • H04Q3/0029—Provisions for intelligent networking
  • H04Q3/0045—Provisions for intelligent networking involving hybrid, i.e. a mixture of public and private, or multi-vendor systems

Definitions

• the Gigabit Ethernet data is processed and switched onto the appropriate drop port(s) 26A, 26B, 26C, 26D and/or forwarded to the downstream SAS (or, possibly, DS) on port 24B based on the entry for the corresponding Routing ED in a routing table kept at the SAS.
• the I and Q channels are digitized and passed on to the QAM-to-byte mapper 629 for conversion to a byte-wide data stream in the PHY device 606 (FIG. 10).
• Carrier and clock recovery for use in synchronization at symbol and frame levels, are performed during periodic training periods described below.
• a carrier recovery PLL circuit 668 provides the I and Q carriers to the multipliers 656, 658.
• a clock recovery delay locked loop (DLL) circuit 676 provides clock to the QAM-to-byte mapper 629.
• DLL delay locked loop
• the receiver 604B At the falling edge of the carrier recovery period 675, the receiver 604B counts a programmable delay, then the receiver 604B enables the clock-recovery DLL circuit 676. This timing recovery occurs in relation to the symbol timing recovery signal 677.
• the SYNC timing circuit closes switch 673 to connect the carrier recovery PLL circuit 668 and clock recovery DLL circuit 676. Following these short update periods, the receiver is in a normal operational mode in which it receives data frames 620.
• the receive section 606B includes receive Mu 690, byte and symbol sign descrambler word generator 692, byte descrambler 694, Gray decoder and symbol sign descrambler (demapper) 696 and PHY deframer 698.
• the demapper 696 corresponds to the QAM-to-byte mapper 629 (FIG. 14).
• the QoS bits are used to prioritize traffic.
• the Control bits and QoS bits are described further herein.
• packets can be routed to the appropriate DS, SAS or NIU. All user data is transmitted by the NIU onto the Home LAN using standard Ethernet frames.
• the 12-bit RED allows the system to address 4096 entities which can be used to indicate an entity (Unicast), a group of entities (for Multicast) or all entities (for Broadcast).
• the different REDs are specified as follows in Table 8.
• a sequence of events leading to RED and EP Address assignment in the present system is described as follows and shown in FIG. 22.
• a newly installed or initialized network element e.g., DS 114, SAS 116 or NIU 119; FIG. 3 broadcasts a DHCPDISCOVER message looking for the Tag/Topology server 132.
• the options field 826 (FIG. 21) in the DHCPDISCOVER is populated to differentiate between a network element and other user devices.
• All "registered" devices in the upstream path between the initialized network element and the ODS 112 (FIG. 3) append their MAC Address and Physical Port numbers to the DHCPDISCOVER message in options field 826. This is done in order to construct a topology of the Access Network and is described further herein.
• a relay agent of the router 110 (FIG. 3) relays this message to all known DHCP servers.
• the end of the options field is indicated by the END option 842.
• the Tag/Topology server tracks and constructs a network topology.
• the Tag/Topology server can also request the Network Management Systems (NMS) 134 (FIG. 3) to prompt individual network elements to re-send their topology information at any time.
• NMS Network Management Systems
• Initial topology discovery takes place using standard DHCPDISCOVER messages. As a network element boots up, it broadcasts a DHCPDISCOVER request as described above. The control bits are set as described further herein.
• Access Network servers These are special control messages that are meant for a network element and, for security reasons, should not reach the end user.
• the control bits are also useful for dynamically determining the NIU that serves an end device as described further herein.
• the routing ED (RED) of a DS or SAS uniquely identifies the device. Hence, any frame that has the unique RED of the DS or SAS is forwarded to the processor 610 (FIG. 10) associated with that DS or SAS. All frames with Broadcast RED are forwarded to the processor and to all downstream egress ports. All downstream messages to the DS/S AS are processed by the TCP/IP stack.
• the control bits have no significance at the DS/SAS as indicated in Table 10.
• the NIU maintains a clock, which is used for updating the state of the token buckets for all service instances, the NEU also maintains a state variable, X, for each token bucket. At the end of each clock period of duration T ms, the NEU updates the state variable, X. It does this using the following update equations:
• Packet size restrictions can also be enforced at this stage. For instance, if a service instance is set up with a limit on the maximum packet size, a packet belonging to that service instance can be dropped at this stage if its size exceeds the corresponding limit. (Alternatively, packet size restrictions may be enforced at the traffic policing stage.)
• the packet processing stage 1306 also includes some service independent processing that all packets need to undergo. This service independent processing follows service specific processing, and includes such things as the attachment of a Access Network label, with the QoS field filled with the QoS class associated with the packet's service instance, and recalculation of the packet's Ethernet check-sum. At the end of this processing, a packet is ready to go out and is handed to the egress buffer control stage 1310.
• the transmission scheduler uses these values in its scheduling decisions Because of the fact that once packets are handed to the hardware (the DMA controller, in particular) for copying them into the modem buffer they cannot be stopped from being transmitted, tight coordination is required between the transmission scheduler and the hardware to ensure that only a manageable quantity of packets is handed to the hardware at any time. This is achieved as follows.
• the modem buffer 1314 has a limited amount of buffer space e.g., 3200 bytes. Periodically, e.g., every 100 microseconds, the hardware writes into a designated register the amount of memory space available in the modem buffer at that instant, and sends an interrupt to the CPU. The CPU processes this interrupt at the highest priority, and as part of this interrupt processing calls the function representing the transmission scheduler task.
• the upstream packet handling features ensure low latency for the delay sensitive, high priority packets while keeping the overall throughput high and maintaining fairness in the treatment of the traffic belonging to the lowest (UBR) priority class.
• an intelligent transmission scheduling discipline is used at the intermediate network elements. This scheduling discipline, which combines priorities with weighted round robin scheduling, provides for low delays for high priority traffic and fairness in the treatment of UBR traffic.
• the transmission scheduling discipline for intermediate network elements is defined such that for each such device, each of the top three QoS classes (i.e., ⁇ Classes 1,2 and 3) have a common queue while there are per link queues for the fourth (UBR) class (i.e., Class 4).
• UBR fourth
• the transmission scheduling discipline observes strict, non-preemptive priorities between the QoS classes, and uses a weighted round robin discipline to allocate the available system capacity (i.e., trunk bandwidth) in a fair manner to UBR traffic carried by different links. Packets in the same queue follow the FEFO order among them. Moreover, it does not schedule a packet for transmission if the flow control flag for the corresponding QoS class is OFF.
• the Resource_Request message When a call agent wants to reserve resources for a connection, it sends a Resource_Request message to the CAC server as shown in FIG. 37 A. All messages in this protocol begin with a message type field 1112 that is one byte long. Besides the message type field, the Resource_Request message includes an identifier 1114 of the call agent, an identifier 1116 of the connection for which resources are being requested, the EP address and port number 1117 of the end-user device attached to the Access Network that is involved in that connection, the IP address and port number 1118 of the far end device and a traffic descriptor 1120.
• the identifier of the call agent can be its public IP address.
• the identifier of the call is a four-byte integer that has been selected by the call agent to refer to that connection.
• RequestJDenial messages is filled with the same connection identifier used by the call agent in the original Resource_Request message.
• Request_Grant and Commit_Confirm Messages for Provisioned Services can include the following fields: Message type, CAC Server ID, NEU ED, Provisioned Service ED, Service type, Traffic Descriptor, Packet Classifier Information and Service specific options.
• Request_Denial and Release_Confirm Messages for Provisioned Services include ⁇ he fields Message type, CAC Server ED and Provisioned Service ED.
• a lesourceJRelease Message for Provisioned Services includes Message type, rovisioning Server ED and Provisioned Service ED fields.
• the Service Specific Options field begins with a 'TSTumber of Options" subfield 1434.
• the value contained in this field indicates how many Option entries -70-
• the Message Type field 1460 identifies this message as a Modify-Parameters message, whereas the contents of the Message Number and Connection/Provisioned Service ID fields have the same meaning as the corresponding fields in the Setup message.
• the field Modification Type 1466 specifies the kind of change the CAC server wishes to make to the connection or provisioned service identified in the Connection / Provisioned Service D field 1464. Table 18 gives the relationship between the contents of the Modification Type field and the corresponding parameter modification being sought.
• the Conn-Parameters message uses the value contained in the Message Number field of the Get-Parameters message to help the CAC server relate the response (the Conn-Parameters message) to the correct request.
• the CAC server can send a Get-Parameters message to an NIU with the connection identifier parameter set to a wildcard. In this case, the message indicates a request for parameters associated with all connections established at the NIU.
• the NIU then responds with a Conn-Parameters message carrying the parameters associated with all the connections established at the NIU. To allow for the desired flexibility in this message, it has the structure shown in FIG.
• the message format shown in FIG. 43 provides the needed flexibility to allow the NIU to respond to different versions of the Get-Parameters message and also to be able to provide the various pieces of information associated with a connection or a provisioned service that are stored in its local memory.
• the Get-Parameters message asks for the parameters of a specific connection identified by its ED, if the NIU has a connection with that identifier, it sends a -74-
• Connection ED is the same as what was specified in the Get-Parameters message, but the rest of the fields are all set to 0. Finally, if the Get-Parameters message uses a wildcard in the Connection Identifier field, the "Number of Connection Parameter Sets in Message" field in the Conn-Parameters response is set equal to the number of connections that have been established at the NEU, followed by that many sets of connection parameters. The field “Total Number of Connections" in all of these cases is set equal to the number of connections / provisioned service instances established at the NIU. The structure of the connection parameter subfields and their contents are similar to those of the corresponding fields in a Setup message.
• Connection data represents the information stored by the CAC server for each of the connections / provisioned services set up on the portion of the Access Network being controlled by the CAC server. This information enables the CAC server to respond to call agent (or provisioning server) messages involving these connections and identify the resources being used by each of them so that when one of them is terminated, the CAC server can release the resources that were set aside for that connection and update the utilization state of the critical segments involved in that connection.
• the connection data maintained in the CAC server includes the following fields: call agent / provisioning server ID, connection / provisioned service JD, connection state,service type, NEU ED, critical segments list, original traffic descriptor, derived traffic descriptor, packet classifier information and service specific options. -77-
• the CAC server reserves resources for the connection on its critical segments and updates the utilization state of these segments, the connection state is changed to RESERVED.
• the CAC server receives a Resource_Commit message from the call agent / provisioning server and responds to it with a Commit__Confirm message, it changes the state of the connection to COMMITTED.
• the QoS Class subfield represents the QoS class accorded to the connection / provisioned service by the CAC server.
• the Maximum Burst Size and Maximum Packet Size subfields have the same interpretation as the corresponding subfields of the Original Traffic Descriptor.
• the CAC Server determines the effective bandwidth and QoS Class associated with a connection / provisioned service as functions of the various subfields of the Original Traffic Descriptor, and uses the Derived Traffic Descriptor in its messages to the NIU. The Original Traffic Descriptor remains hidden from the NIU.
• This algorithm updates the utilization data for the critical segments in the Access Network whenever a connection is established or torn down.
• utilization is used in a rather general sense here, and, depending on the effective bandwidth computation being used, may or may not represent true utilization. If sustained throughput rate is used as the effective bandwidth of a connection, the utilization level on critical segment due a given QoS class represents the true bandwidth utilization due to that class on that segment.
• Communication with external entities such as call agents involves traffic flow over the service provider's network which is non-proprietary e.g., standard protocols such as TCP or UDP over EP.
• the CAC server implements these protocol stacks to support actual signaling that takes place between it and the call agents.
• the (higher level) signaling protocol is selected such that it is supported by the call agents interacting with the CAC server.
• the resource reservation protocol described above is intended to identify the requirements for the messages that need to be exchanged between the call agents and the CAC server for QoS management purposes. The actual protocol used depends upon what is supported by the call agents.
• the CAC server sends a DISCOVER_NIU message downstream. This message has the End Device IP Address as Destination JP Address of the IP Packet. »The Router constructs a Layer-2 frame.
• the Destination MAC Address is the End Device MAC Address.
• the ODS looks at the source IP Address, identifies this message as a control message and inserts the appropriate control bits and RED corresponding to the end point. »The packet is routed through the Access Network (based on the RID) and reaches the NEU.
• the mEN is shown in FIG. 46 and provides Gigabit Ethernet and legacy services to 100 homes, relays legacy services to 3 additional ports, and facilitates fiber-optic transmission between the headend and successive mFNs.
• the mFN subsumes the function of legacy Video, DOCSIS, and Telephony RF transmission normally performed by the Distribution Amplifier (DA) found in conventional HFC systems.
• the mFN provides Wavelength Add Drop Multiplexing (WADM) 1220 in both upstream and downstream directions.
• Ethernet traffic from optical transceivers is combined/separated from legacy HFC RF signals traveling to/from the subscriber.
• MAC and QoS operations are performed by an ASIC within the mFN.
• a very powerful aspect of the Access Network of the present system is that it affords many ancillary monitoring, management, auto-configuration, -84-
• Downstream linlc establishment includes complementary transmission at east port modems and default transmission on drop port modems (complementary transmission on all four DS ports).
• carrier and frame SYNC are followed by loop-back through each child.
• East port modem linlc inactivity timeouts triggers BIST, but drop modem link inactivity does not.
• FLASH memory is used to store element configuration settings for possible rapid recovery after disruptions such as those caused by, e.g., power hits.
• slope equalization is performed using a Quadrature Nulling (QN) technique starting at 1620.
• QN Quadrature Nulling
• the QN technique involves a four- way handshake, which is facilitated by the parent initially sending only hi-Phase Data.
• the QN technique involves adaptively adjusting the slope equalizer until Q-Channel integrated data power is at a local minimum. Beyond initial slope adjustment during -90-
• the correct carrier frequency is known a priori. Therefore, the local oscillator frequency is set to f (which is the same carrier received during the upstream boot operation) in the case of the east modem.
• QN-based slope equalization can be performed. Successful slope equalization will be conveyed to the child by transmitting Q-Channel data as well as I-Channel data.
• the frame recovery process can begin at 1716 as was done in the upstream boot procedure.
• Post boot coaxial cable slope drift will be corrected in exactly the same manner as described in the upstream boot procedure.

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• Computer Networks & Wireless Communication (AREA)
• Multimedia (AREA)
• Data Exchanges In Wide-Area Networks (AREA)
• Optical Communication System (AREA)

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• 2001
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