Abstract: Duplicate participants (e.g., cloned subscriber units) (274) are detected in a communication network, such as a hybrid fiber/coax (HFC) cable television network or the like, by monitoring the physical layer of the network to detect transmission differences between such units. The subscriber units (14, 16, 18, 274, 276) may be cable modems that transmit upstream signals with associated identifiers to a headend (10, 200), e.g., to access the Internet or for telephony. Measured characteristics of the upstream signals can include: (1) propagation time (235), (2) frequency (240), (3) power (245), and (4) spectral characteristics (250). For propagation time, the reception time of the upstream message can be compared to a headend clock (215) and also to other messages with the same modem ID. For spectral characteristics, adjustment coefficients can be provided to the units to normalize the spectrum of the upstream signal to a baseline spectrum.

Abstract: An addressing method and a system for assigning network addresses such that access to a network resource remains local. This is accomplished by allocating a local network address in favor of a remote network address. A process executing on a processor makes a request for a network address. A local network address is located in memory of the processor executing the process. The local network address is assigned, if available. Otherwise, a remote network address located in the memory of another processor is assigned. Preferably, the network address request contains information about on which processor the requesting process is running. Using this information, the present invention is able to select a network address that resides in the local memory of that processor. The network address allocation system of the present invention includes a network address allocator that uses the method of the present invention as outlined above.

Abstract: An adjustable connection admission control method and device for packet-based switches assigns equivalent bandwidths to variable speed connections. The equivalent bandwidths of the variable speed connections are increased or reduced by a scaling factor to achieve an assigned bandwidth. The method and device determine whether to accept or refuse new variable speed connections based on whether the sum of equivalent bandwidths for existing variable speed connections and new variable speed connections exceeds the bandwidth available to variable speed connections. The connection admission control method and device also determines whether to accept or refuse new constant speed and new unspecified connections. For constant speed connections, the sum of existing and new constant speed connections is obtained. If the sum of bandwidths for existing and new constant speed connections exceeds a maximum factor, the bandwidth available to constant speed connections is reduced by a constant speed traffic factor.

Abstract: A method and apparatus for avoiding network congestion. An exemplary packet forwarding device may apply policy rules to incoming packets to assign relative drop probabilities to the packets based on the priority of the packets. In times of network congestion, packets may be selectively dropped according to their associated drop probability.

Abstract: Providing transport protocol within a communication network having a lossy link. The receiver distinguishes between packets received with non-congestion bit errors and packets having been not at all received due to congestion. When packets are received with non-congestion bit errors, the receiver sends selective acknowledgments indicating that the packets were received with bit errors while suppressing duplicate acknowledgments to prevent the invocation of a congestion mechanism.

Abstract: The frame words of the preferred embodiment are especially suitable for frame synchronization and/or channel estimation. By adding the autocorrelation and cross-correlation functions of frame words, double maximum values equal in magnitude and opposite polarity at zero and middle shifts are obtained. This property can be used to slot-by-slot, double-check frame synchronization timing, single frame synchronization and/or channel estimation and allows reduction of the synchronization search time. Further, the present invention allows a simpler construction of a correlator circuit for a receiver. A frame synchronization apparatus and method using an optimal pilot pattern is used in a wide band code division multiple Access (W-CDMA) next generation mobile communication system.

Abstract: The present invention makes it possible to efficiently transmit data for statistical multiplexing which is required for control using statistical multiplexing. By utilizing private packets, respective encoding devices transmit encoding difficulties serving as the data for statistical multiplexing to a multiplexer (4) via the same transmission channels as encoded video data and audio data are transmitted. The multiplexer (4) conducts multiplexing processing on data supplied from the respective encoding devices at a first rate R1 larger than a transmission rate on a transmission channel of a subsequent stage, and outputs a transport stream (TSd) including the private packets to a statistical multiplexing computer.

Abstract: A method and apparatus for generating a performance indicator in a high-speed communication system. A plurality of disparate communication status signals with differing formats from a transceiver are combined in a logic module to create a single link quality indicator signal. The link quality indicator signal is used to encode different operational states of the transceiver from fully operational, to marginally operational, to failed. The link quality indicator signal is advantageously employed to drive a LED creating a visual performance indicator.

Abstract: A method and apparatus comprises a controller to establish a call session between a first endpoint and a second endpoint. Without exchanging call setup signaling with the first endpoint, the controller is able to pivot the call session from the second endpoint to another endpoint so that media communication can occur between the first and other endpoints. The first endpoint remains “anchored” in the call session. The pivot is accomplished by sending a call request to the other endpoint and exchanging messages with a media portal that controls the communication of packets between endpoints. The media portal contains a network address and translation module that performs translation of addresses and/or ports of media packets communicated from one endpoint to another.

Abstract: A switched router for transmitting packetized data concurrently between a plurality of devices coupled to the switched router. The devices are coupled to the I/O ports of the switched router. The switched router is then programmed to route packets of data from various source ports to several destination ports. Different packets may be transmitted concurrently through the switched router. The packets are comprised of a command word containing information corresponding to packet routing, data format, size, and transaction identification. Furthermore, the command word may include a destination identification number for routing the packet to a destination device, a source identification number used by a destination device to send back responses, a transaction number to tag requests that require a response, and a packet type value indicating a particular type of packet.

Abstract: A network device transfers variable-length data frames across a synchronous network employing a multiple-channel synchronous transport signal. Encapsulation logic encapsulates each data frame in a point-to-point frame including a body portion of the data frame and a length value located in a beginning portion of the point-to-point frame. Segmentation logic divides each point-to-point frame into fixed-sized segments, a first segment carrying the beginning portion of the point-to-point frame. Transmitting circuitry transmits the frame segments as payloads of at least one channel of the synchronous transport signal, the payloads being marked so as to be identifiable. Receiving circuitry receives payloads of at least one channel of the synchronous transport signal and from each received set of payloads regenerates a corresponding point-to-point frame using the length value from the first segment thereof.

Abstract: A method and system for a queue identification (QI) system which significantly reduces resources required to identify a process associated with receiving an incoming packet is provided. A QI mechanism is used as a TCP option. During a TCP connection establishment process, QI numbers are exchanged for both a sending port and a receiving port of the connection. After the connection is established, the destination QI's number is inserted in a Transmission Control Protocol (TCP) header on outbound packets.

Abstract: A host interface dual active fibre channel adaptive hub includes two fibre channel arbitrated loops, a loop healing switch coupled to both loops, and four loop resiliency circuits. Each loop has a controller and a host server coupled to it through a respective loop resiliency circuit. The host servers issue I/O requests to the controllers through the dual fibre channel arbitrated loops. Therefore in normal operation, with both loops active and both controllers operational, the system provides twice the bandwidth of a conventional single loop fibre channel arbitrated loop system. The loop resiliency circuits detect failures in the controllers. If a loop resiliency circuit detects a failure in a controller, the loop resiliency circuit outputs a failure signal to the loop healing switch. A failed controller also notifies the loop healing switch that it has failed. The loop healing switch then switches to couple the two fibre channel arbitrated loops into a single loop.

Abstract: A system for determining which of several satellites to tune an integrated receiver/decoder (IRD) to for receiving electronic program guide data is described. The system scans a plurality of multi-switch ports attempting to acquire a digital marker associated with a predetermined network identifier and polarity. The acquired marker contains information representing a satellite network and a satellite transponder number. In this manner, the system automatically configures the IRD to present electronic program guide information associated with available satellites while excluding guide information associated with unavailable satellites.

Abstract: In an ad-hoc radio communication system comprising a plurality of stations (100) formed into at least one network (102a,102b), each station (100) is assigned a rank representative of its suitability for performing the role of master station in a network (102a). The rank may for example be assessed depending on the performance of the station's antenna (204) or its access to mains power. It is arranged that the station (100) having the highest rank in a network (102a,102b) performs the role of master for that network, thereby improving the efficiency of communication in the network.

Abstract: Disclosed is a mobile communication system including a network constituted of at least one switching center and a plurality of base stations, and a mobile station which communicates with the base stations simultaneously. The system permits varying transmission delay between the switching center and the base stations according to the type of services available to the mobile station. The object of the present invention is to propose a communication which permits varying transmission delay according to the type of service currently employed, and to promptly recover a synchronization state even if an out-of-sync state happens. To attain the object, a memory means (mobile switching center processor 32) stores transmission delay characteristics corresponding to services which are available to the mobile station.

Abstract: In a multipoint-to-point link, packets are transmitted over a shared medium to a central node in response to permits. The central node issues permits to a multipoint node on the basis of a queue size record, held at the central node. The queue record is updated on receipt of a queue size report (request for permits) from the multipoint node. Due to the transmission delays across the link, an erroneous queue value can be recorded at the central node when permits and a request for permits are sent at about the same time. This problem is overcome and the transfer capacity improved when the central node holds a record of the permits sent during the preceding round trip delay. Any incoming reqest for permits is then adjusted by the number of stored permits before it is utilized to update the queue record.

Abstract: An apparatus for a multi-service network architecture for processing network traffic arriving on a network connection is disclosed. The multi-service network architecture has a plurality of network connection components residing on a single platform and a processor coupled to the network connection components. The processor is configured to execute a predetermined one of a plurality of software images corresponding to the type of network traffic arriving on the network connection and to selectively enable at least one of the network connection components according to the predetermined software image.

Abstract: A method of wirelessly transmitting or receiving a packet of information, and an apparatus to wirelessly transmit or receive a packet of information. In the case of transmitting, the method includes streaming a data element, including at least some of the contents of the packet, over a network link during transmit time, including encrypting the data element during the streaming in real time prior to the transfer over the network link. In the case of receiving, the method includes streaming a data element, including at least some of the contents of the received packet, over a network link during receive time, including decrypting the data element during the streaming in real time after to the transfer over the network link. The transmitting or receiving is by a station of a wireless network and the streaming is to or from the station from or to a network device coupled to the station by the network link.

Abstract: Data flows generated in accordance with a connected mode protocol and formatted in packets in accordance with a non-connected mode protocol are transmitted via an ATM network. A set of virtual circuits of the ATM network is assigned in advance to each pair of access points of the ATM network, without allocating transmission rate resources to them. When an access point receives a request, formulated in accordance with the connected mode protocol, to establish a connection between a source address and a destination address accessible via another access point of the ATM network, an available virtual circuit is selected from the set assigned to this pair of access points and a resource management cell containing a request to activate the virtual circuit is transmitted on the selected virtual circuit. When this cell is received by a node of the ATM network located on the selected virtual circuit, a transmission rate resource is allocated, if it is available, to the selected virtual circuit.