Abstract: Limiting or controlling access to various services thereby performing a firewall function. An access router may permit or deny a packet based on at least a portion of a unique bit string (or context information) which replaced layer 2 header information (e.g., the layer 2 (e.g., MAC) address). Further, a particular quality of service may be indicated by at least a part of the unique bit string (or context information). The service provided to a group of customers, that group of customers being defined by at least a portion of the unique bit string (or context information), may be monitored. Multicast groups may be supported by checking at least a part of the unique bit string (or context information) to determine whether or not a customer associated with that port is permitted to join the multicast group.

Abstract: An IP multicast aware switched digital method and apparatus are provided in a settop unit wherein packet streams containing reference information are multicast while a select set of program information is routed to the settop units so that multicast streams can be identified and full content can be routed individually to the settop unit for decoding. Specific or preferred embodiment applications include simultaneous output and interactive communication with a television (true video on demand), computer (Internet access), videophone and telephone.

Abstract: A system and method are provided for framing messages in a data streams encoded with redundant information for transmission and recovering the messages at a receiver. The transmission method accepts an energy waveform representing N words at a first bit rate, encoded with redundant information, where each word includes P number of bits. The N words are transformed, creating N transcoded words, where each transcoded word includes Q number of bits, and where Q<P. The N transcoded words are mapped into M lanes in a buffer memory, where M>1 and each lane receives a frame of N/M transcoded words. A frame alignment marker is generated and mapped into each frame. Each frame is represented as an energy waveform that is transmitted on a corresponding physical lane at the first bit rate divided by M.

Abstract: A network switch includes an input layer to receive a data stream with a set of cells. Each cell includes data and a header to designate a destination device. The input layer includes a set of input layer circuits. A selected input layer circuit of the set of input layer circuits receives the data stream. The selected input layer circuit includes a set of queues corresponding to a set of destination devices. The selected input layer circuit is configured to assign a selected cell from the data stream to a selected queue of the set of queues. The selected queue corresponds to a selected destination device specified by the header of the selected cell. An intermediate layer includes a set of intermediate layer circuits, each intermediate layer circuit has a set of buffers corresponding to the set of destination devices.

Abstract: A system and method for communication channel and device control via an existing audio channel. A combined communication signal is received from a communication device comprising an audio signal and a modulated carrier signal via an audio channel. The audio signal is separated from the carrier signal. Digital data is extracted from the carrier signal. Device control is performed utilizing the extracted digital data.

Abstract: A system and method for remotely controlling an increased number of subsystems having an onboard locomotive control unit (LCU) and two associated operator control units (OCUs) on a single wireless channel. A time slot is assigned to each subsystem for making two-way transmissions to control the locomotive. A signal from an external timing source synchronizes each subsystem to minimize interference between transmissions from different subsystems. Time slots are assigned manually or automatically over a wireless network or by the LCU after monitoring the channel. The LCU automatically selects the direct or repeater transmission path depending upon whether or not it receives polling message responses from its associated OCUs. A GPS receiver in each subsystem receives the synchronization signal and provides geographic positioning data so the LCU can determine when to execute predefined, position-based commands. The secondary OCU may be turned off and rejoined to the subsystem without ceasing operation.

Abstract: The present invention relates to a method and a system of flow control in a communication network. The method comprises determining if at least one sender buffer has a sufficient number of credits. The sufficient number of credits informs the sender buffer if the receiver buffer has an available buffer space corresponding to at least one data packet. The method further comprises transmitting the at least one data packet to at least one receiver buffer, if the at least one sender buffer has the sufficient number of credits. If the sufficient number of credits in the at least one sender buffer are absent, a data packet is transmitting speculatively to the at least one receiver buffer. If a negative acknowledgement is received for the transmitted data packet, a copy of the data packet can be retransmitted to the receiver buffer.

Abstract: A multiprocessor system used in a car, home, or office environment includes multiple processors that run different real-time applications. A dynamic configuration system runs on the multiple processors and includes a device manager, configuration manager, and data manager. The device manager automatically detects and adds new devices to the multiprocessor system, and the configuration manager automatically reconfigures which processors run the real-time applications. The data manager identifies the type of data generated by the new devices and identifies which devices in the multiprocessor system are able to process the data.

Abstract: A method that changes the selection of a 2:1 multiplexer that receives a first output signal from a first framer and a second output signal from a second framer. The first output signal is the same as the second output signal. An apparatus having a framer and a 2:1 multiplexer that receives an inbound signal from the framer. A first multiplexer receives at least one signal from another framer and the 2:1 multiplexer has an input coupled to an output from the first multiplexer. A second multiplexer receives at least one signal from the other framer and the second multiplexer has an output coupled to an input of the framer for an outbound signal.

Abstract: A variable rate transmission system where a packet of variable rate data is transmitted on a traffic channel if the capacity of the traffic channel is greater than or equal to the data rate of the packet. When the rate of the packet of variable rate data exceeds the capacity of the traffic channel, the packet is transmitted on a traffic channel and at least one overflow channel. Also described is a receiving system for receiving and reassembling the data transmitted on the traffic channel and at least one additional overflow channel.

Abstract: A method for providing a push-to-talk communication session includes facilitating a push-to-talk communication session among a full duplex endpoint supporting simultaneous two-way communication and a plurality of half duplex endpoints. Communications are received from and transmitted to the full duplex endpoint along a two-way communications path. The method includes blocking communications received from the full duplex endpoint while one of the plurality of half duplex endpoints has floor control in the communication session and receiving from the full duplex endpoint in the two-way communications path a floor control signal comprising a request to transmit communications in the communication session. The method includes, in response to receiving the floor control signal, providing floor control to the full duplex endpoint and transmitting to the plurality of half duplex endpoints communications received from the full duplex endpoint.

Abstract: A method for wirelessly connecting a computer network to a destination device located at an unknown location in response to a request from a requesting device. The method of the present invention creates a more versatile wireless computer network by enabling devices within the computer network to efficiently wirelessly connect to mobile devices that are not connected to the computer network but are in range of at least one wireless access point. Therefore, the network can efficiently dynamically adjust to the movement of particular wireless devices throughout the network. Likewise, the method effectively increases the capabilities of the network by enabling devices within the network to efficiently connect with devices that are not actively communicating with the network. The method includes a series of searching routines which are performed at each access point to locate the destination device.

Abstract: In an apparatus, there are provided an IP transmitting and receiving unit for transmitting and receiving an IPv4 packet and an IPv6 packet; an IP header converting unit for performing a mutual conversion of the IPv4 packet and the IPv6 packet by an IP header conversion; a DNS substituting unit for receiving a domain information capturing request sent from an IPv4 terminal or an IPv6 terminal and substituting its process; an IPv4 address capturing unit for capturing an IPv4 address from a DHCP server; and an IP address conversion information holding unit for holding an IPv6 address of the IPv6 terminal and the IPv4 address captured by the IPv4 address capturing unit in correspondence to each other. Thus, a communication with the IPv4 terminal can be executed without preliminarily fixedly allocating the IPv4 address to the IPv6 terminal.

Abstract: A media access controller (MAC) is configured with a header creator circuit. The header creator circuit is configured with logic for receiving a data packet and determining whether the received data packet has an existing packet header prepended thereto. The header creator circuit is further configured to determine if the length of the received data packet includes a cyclic redundancy code. Still further, the header creator circuit is configured to determine a packet header length field value for the received data packet. If the header creator circuit determines that a cyclic redundancy code needs to be included with the received data packet, then the header creator circuit is able to generate a CRC flag. If the data packet needs to be encrypted, then the header creator circuit will generate an encryption flag if it is determined that the received data packet should be encrypted. Finally, the header creator circuit generates a packet header having a plurality of fields.

Abstract: A method and apparatus for analyzing traffic arriving at and/or departing from a traffic aggregate defined as a given IP-related protocol, a given port associated with a given protocol, an IP address or subset of IP addresses, or by other traffic aggregation, during a given time interval, to determine whether there is a significant increase or decrease in traffic aggregate's traffic volume as compared to the traffic aggregate's expected traffic volume are disclosed. In one embodiment, the present method defines a traffic share ratio threshold associated with a given protocol or a given protocol port or a given IP address or a given subset of IP addresses or other traffic aggregation using said collected volumetric traffic data. The present method also defines a current traffic share, a baseline traffic share and a traffic share ratio to be evaluated for the said traffic aggregate.

Abstract: Disclosed is a method and apparatus for improving LAN availability and robustness employing adjacency status self-discovery on segment-to-segment communications paths. In some embodiments, the method and system may employ Logical Link Control Type 1 test frame messages between segment nodes to determine status. Adjacent node status may be determined by waiting a period of time for an acknowledgment message and marking the tested link as “down” if no response is received. Also disclosed is a method for compacting data transmitted over a network to reduce overhead.

Abstract: A method for managing data traffic in nodes in a fabric network, each node having internally-coupled ports, follows the steps of establishing a managed queuing system comprising one or more queues associated with each port, for managing incoming data traffic; and accepting or discarding data directed to a queue according to the quantity of data in the queue relative to queue capacity. In one preferred embodiment the managed system accepts all data directed to a queue less than full, and discards all data directed to a queue that is full. In some alternative embodiments the queue manager monitors quantity of data in a queue relative to queue capacity, and begins to discard data at a predetermined rate when the quantity of queued data reaches the threshold. In other cases the queue manager increases the rate of discarding as the quantity of queued data increases above the preset threshold, discarding all data traffic when the queue is full.

Abstract: First to N-th circuit interface units 1041 to 104N corresponding to first to N-th circuits 1031 to 103N include an input traffic counter unit 1141, etc. and an output traffic counter unit 1151, etc. for counting the traffic of input and output. A traffic counter monitor block 123 in a control unit 105 specifies an input traffic counter unit 114 and an output traffic counter unit 115 of two circuits 103 through a switch unit 102 in a specific packet flow, and periodically obtains the count values, based on which the utilization rate, the discard rate, etc. of the corresponding circuit 103 are obtained to monitor the traffic. This makes it possible to monitor packet signal traffic when a plurality of circuits are to be switched without capturing each packet signal.

Abstract: A method and system for automatic modem bandwidth detection. The method includes the step of transmitting a plurality of probe packets from a router to an aggregator via a modem. A plurality of reply packets are the detected wherein the reply packets are transmitted from the aggregator to the router via the modem in response to the probe packets. An upstream data transmission rate of the modem is then determined based on a relative rate of transmission of the probe packets transmitted by the router to the reply packets received by the router.

Abstract: A demand-based connection management satellite communication network includes a plurality of geographically distributed earth stations, each earth station having a frame relay protocol-based switch for interfacing message signals between terminal devices and modem unit. One of the earth stations is a hub station whose modem unit includes plural demodulators tuned to carrier frequencies transmitted from other, remote stations. Each remote station has at least one hub-programmable demodulator and/or a programmable modulator. When an originating station receives a request from a terminal device for connectivity with a terminal device at a destination station, it transmits a connectivity request message to the hub station. In response, the hub station checks a demodulator and/or modulator frequency assignment database for demodulator availability.