Abstract: Data transmission system for transmitting packets of data from a source workstation (10) to a destination workstation (40) wherein the packets of data are transmitted over at least a first IP network (14) and a second IP network (30) between an ingress node (20) connected to the source workstation in the first network and an egress node (38) connected to the destination workstation in the second network. The system comprises a local reservation server (26) in the first network accessible by the source workstation and a remote reservation server (42) in the second network accessible by the local reservation server. The local reservation server includes connection setup means for setting up a virtual connection meeting a predefined requirement of Quality of Service from the ingress node to the egress node in response to a request from the source workstation and bandwidth request means for requesting additional bandwidth in the second network to the remote reservation server.

Abstract: Methods and arrangements for facilitating the further development of a distribution tree among at least three nodes in a distributed network. A network performance measurement associated with the propagation of a message between the publisher node and the joining subscriber node is ascertained, as well as each network performance measurement associated with the propagation of messages between the publisher node and each existing subscriber node. The network performance measurement between the publisher node and the joining subscriber node is compared with each network performance measurement between the publisher node and each existing subscriber node, and a joining subscriber node is established as a child of another node based on the comparison of network performance measurements.

Abstract: A method and apparatus for adapting a network topology including at least one hybrid digital cross-connect system (DCS)/SONET ring structure such that DCS network elements are managed by a DCS element management system, while SONET network elements such as ring structures are managed by a SONET element management system. A digital link is created to separate pure DCS equipment from SONET equipment within the hybrid DCS. Based on this separation, the hybrid DCS is logically decomposed into separate DCS and SONET equipment such that a SONET ring structure including an add-drop multiplexer (ADM) included within the DCS may be managed as a homogeneous SONET ring by a SONET network element manager, while the DCS equipment is managed by a DCS element manager.

Abstract: An apparatus comprising a media access controller (MAC), a configurable packet switch, and a network protocol stack in silicon. The network protocol stack may be configured to couple the media access controller to the configurable packet switch.

Abstract: Internet protocol based transmissions have historically been transmitted on a best efforts basis. There are proposals to provide differentiated services to allow different packets to be delivered with different service qualities depending on the bandwidth requirements of a particular flow. By performing bandwidth monitoring within the core network and performing packet dropping and/or queuing at the network ingress, the need for packet dropping and/or queuing within the core network is removed and furthermore the core network resources are not used by packets which will not be delivered to their destination but will instead be dropped within the core network.

Abstract: The present invention is generally directed to a system and method for encoding a DSL information bit stream and decoding a corresponding encoded DSL symbol. In accordance with one embodiment, an apparatus for encoding a DSL information bit stream is provided having a switch with an input configured to receive a DSL information bit stream and at least two outputs. An encoder is provided and coupled to a first output of the switch. A serial to parallel converter is provided and coupled to both an output of the encoder and a second output of the switch. Finally, a mapper is provided and coupled to an output of the serial to parallel converter through multiple paths. Preferably, a first coupling path between the serial to parallel converter and the mapper is a direct path and a second coupling path includes a second encoder.

Abstract: A broadband terminal interface unit for use in an HFC communication network includes a phase-locked loop for providing a smooth transition between a CMTS-provided “national” clock and a local clock when the CMTS clock is lost (or before it is required). By controlling the tracking range of the PLL, the sensitivity of the circuit is controlled so that some drift in the national clock can be accommodated without unnecessarily reducing the performance of the components within the broadband terminal interface unit.

Abstract: An access server architecture, and methods for use of the architecture, are disclosed. The architecture and methods are designed to increase the scalability of and balance processor load for a network access server. In this architecture, packet forwarding and packet processing are distributed amongst the cards serving the low-speed access lines, such that each line card is responsible for performing forwarding and packet processing for packets associated with the low-speed ports that line card serves. As the number of line cards expands, forwarding resources are expanded in at least rough proportion. The NAS route switch controller, and the high-speed ports, are largely relieved of packet processing tasks because the egress port uses a distribution engine that performs a cursory examination on one or more header fields on packets received—comprehending only enough information to allow each packet to be distributed to the appropriate line card for full processing.

Abstract: A node, and a system including a first node, supporting message transport and segmentation in a communications network having a plurality of nodes, comprising a memory including a database for storing a plurality of segmentation support capability test results, wherein the memory further includes a program module adapted to send a first segmented message, a first segmentation support test message, and a first segmentation support response message, and to receive a second segmented message, a second segmentation support test message, and a second segmentation support response message. The system also includes a second node in electronic communication with the first node, wherein the second node is adapted to receive the segmentation support response message including the segmentation support capability result.

Abstract: In a communications system, data is multiplexed onto a transmission medium at a transmitter and demultiplexed from the transmission medium at a receiver. The clock applied to the transmitter and receiver is a multiplying delay-locked loop in which a delay line provides a multiplied clock which is applied back to its input. A delay adjustment circuit including a proportional phase comparator of low offset adjusts delay in the delay line.

Abstract: A multi-point communication system that comprises a head end unit disposed at a primary site and a plurality of receivers disposed at remote sites. The head end unit includes a transmitter for transmitting OFDM/DMT symbols over a predetermined number of bins across a transmission medium. The OFDM/DMT symbols are transmitted in periodically occurring formatted symbol frames. The cyclic prefix includes a predetermined periodic signal superimposed thereon. The receivers receive the OFDM/DMT symbols over a subset of the predetermined number of bins from the transmission medium and use the superimposed signals to attain symbol alignment. In accordance with a further aspect of the present invention, the receivers apply a predetermined incremental phase shift to received samples corresponding to the received OFDM/DMT symbols to thereby compensate for phase shifts.

Abstract: An approach for supporting settlement of network usage associated with multiple network service providers is disclosed. A settlement system includes a processor that determines a settlement agreement among the network service providers. The settlement agreement specifies rate information associated with traffic exchange among the corresponding networks of the network service providers. A traffic monitor measures source traffic statistics, which is stored in a settlement database. Additionally, the settlement database stores the settlement agreement. The processor computes settlement information based upon the stored traffic statistics; the settlement information includes usage cost differential information for reconciliation of network usage among the various networks.

Abstract: A network traffic shaper provides high-speed, multi-level shaping. The traffic shaper is in communicating relationship with a forwarding engine, and includes a queue controller having a plurality of queues for storing messages, a scheduler for computing release times, at least one time-searchable memory and a corresponding memory controller. Each queue is preferably associated with a corresponding traffic specifier, and a release time is computed for each queue and stored in the time-searchable memory. When a stored release time expires, the message at the head of the corresponding queue is retrieved and is either moved into a different queue or forwarded by the network device. By moving messages through two or more queues, each having its own release time computed in response to a different traffic specifier, the traffic shaper can perform multi-level shaping on network messages.

Abstract: A method and apparatus for analyzing and monitoring packet streams in “real time”. The packet analyzer comprises an input buffer, a real-time analysis unit, a non-real-time analysis unit, a graphics unit, a monitor and a flushing circuit. A packet stream is received into the input buffer where the data is either read by the real-time analysis unit or flushed by the flushing circuit. Messages are passed between the real-time analysis unit and the non-real-time analysis unit to report on detected errors or to update packet stream information. In turn, real time packet stream information are displayed and updated on a display via the graphic unit. A method of detecting framing errors in a packet stream is incorporated by setting a 9th bit in the input buffer for each byte of data in a packet.

Abstract: In order to execute a flow control and a congestion control in a hop-by-hop manner in a data communication among computers connected to different networks, in a data communication between a client A1 and a remote server B, a communication proxy of the remote server B is located in a local server A in an LAN to which the client A belongs. A communication packet to be routed to the remote server B is stolen (received) and passed to a transport layer. A TCP communication between the client A1 and the remote server B is divided into two; a communication between the client A1 and the communication proxy of the remote server B and a communication between the communication proxy of the remote server B and the remote server B.

Abstract: A power control system for controlling the transmission power in a system wherein the transmission power may be gated or capped. The receiver employs a combination of closed loop and outer loop power control. The outer loop is frozen upon detection by the receiver that the signal has been capped or gated.

Abstract: An Orthogonal Frequency Division Multiplexing (OFDM) transmission utilizes random phases across the OFDM sub-carrier components and differential encoding so that the phase information (i.e., phase values) does not have to be explicitly transmitted to a receiver. The OFDM data symbols are differentially encoded so that the phase information on the symbols that are multiplied together in the differential encoder is the same. Assuming use of a differential phase shift keying (DPSK) system, a phase sequence is used having “V” random phase values, where ?n,k is the phase value in the nth sub-carrier in the kth OFDM symbol and is periodic in n with V as the period. A current input symbol is then differentially encoded relative to the Vth previous encoded output from the encoder so that the phase values on the symbols multiplied together in the differential encoding process are the same.

Abstract: A method of facilitating data transfers through a communication network. The method includes forwarding a first data set received from a first interconnect device to a processor. The first data set has transfer instructions and routing instructions associated therewith. The routing instructions specify a destination for the first data set. The method further includes extracting the transfer instructions at the processor and generating a first routing request for the first data set according to the transfer instructions to transfer the first data set to a second interconnect device. The second interconnect device is capable of routing the first data set to the destination. The first routing request has no association to the routing instructions.

Abstract: The invention relates to a method for selecting transmission entities for supporting services within and between networks. The problem of selecting a transmission entity, taking as well a plurality of service parameter as a plurality of transmission entities into account, is solved by sending a request including a set of parameter to a number of transmission entities. The receiver of said request check, whether they support the requested service, or if they can offer an alternative. They transmission to different transmission entities is performed offering a number of alternatives.

Abstract: The communication control system of the present invention includes a cell buffer assembly that is common to a plurality of input ports and stores cells. A writing controller and a reading controller respectively control a process of writing a cell into the cell buffer assembly and a process of reading a cell from the cell buffer assembly. A writing time management memory maps a writing time of each cell to each area in the cell buffer assembly and manages the mapping. A cell discard controller discards a cell having a long elapsed time since the writing time stored in the writing time management memory by the processing, which is independent of the processing by the writing controller and the reading controller. The arrangement of discarding the oldest cell independently of the writing and reading operations enables efficient discard of cells, while ensuring a desired communication rate.