Abstract: A high speed transmission system transfers data streams over a plurality of data links. Each data link may carry a number of bit streams. On the transmitting end, multiplexers serialize the bit streams, which are then transmitted to the receiving end. A clock signal is not transmitted over the optical link. Instead, an indication of the appropriate clock signal frequency and phase is embedded in the transmitted data. At the receiving end, a clock recovery circuit generates a clock signal of an appropriate frequency and phase based on the embedded indication. The new clock signal is used to sample and reconstruct the original data streams.

Abstract: The invention relates to a method for flow control in a switch and a switch controlled thereby. In order to ensure that no or few packets are dropped in a switch because of a congested internal memory, pause frames or stop command messages are sent to upstream senders. When to send pause frames are determined by monitoring the buffer contents of the switch and estimating the total expected contents of the links between the senders and the switch. The pause frames are sent to the most offending senders, i.e. the senders causing the largest queues in the switch.

Abstract: Telecommunications switching systems that require real-time computer control can be controlled using remotely located computers coupled to the switching systems via data links. By coupling several switching systems to one or more centrally located control computers, maintenance staffing can be reduced while increasing overall system reliability by providing back up control computers in multiple centralized locations. Centrally located control computers can be backed up with redundant computers at the central control site.

Abstract: Disclosed is an RF transmitting device of a mobile radio communication base station system in a CDMA system capable of digital-modulating baseband signals which are converted into band spread signals by using the same path which three frequency assignment frequency signals have for an RF in a multi-carrier mobile radio communication system supporting three frequency assignment, digital-coupling the modulated signals, and up-converting the digital-coupled signal into an IF signal and an RF signal in a sequential order, thereby transmitting the up-converted signal.

Abstract: A number of sensors are distributively deployed in a network, either integrally disposed in a number of routing devices of the network or externally disposed and coupled to the routing devices, to monitor and report on network traffic routed through the routing devices. A director is provided to receive network traffic reports from the sensors for the routing devices, and to determine whether moderating actions are to be taken to moderate an amount of network traffic, based at least in part on some of the network traffic reports received from the sensors. In one embodiment, upon determining moderating actions are to be taken, the director further determines what kind of moderating actions are to be taken, including where the moderating actions are to be taken. In one embodiment, the director further instructs appropriate ones of the sensors to cause the desired moderating actions to be applied on the network traffic going through some of the routing devices.

Abstract: In a data packet router, a method for redirecting packets destined for a port comprises steps of monitoring port status on a continuing or periodic basis, updating a port-status table, listing port status as active or failed and an alternative destination for each port, checking the table by circuitry along a packet route for a packet en route, and sending the received packet to the predestined port if the port is listed in the table as active, and sending the received packet to the alternative destination if the port is listed in the table as failed. The method can be implemented essentially anywhere along a routing path where circuitry may support a table look-up and re-tagging packets for alternative destinations. In one embodiment the automatic protection switching is performed in a fabric card, and in another on a line card.

Abstract: A multiplexing equipment included in an ATM network to transmit control line signals for interfacing data communication terminals. The transmission of the control line signals is realized by reserving a field in a payload in a cell format for the control line signal transmission between the data communication terminals, mapping RS/CD, CS, ER/DR, CI of the control line signals at intervals based on a terminal speed, multiplexing the mapped control line signals at the transmission side, and separating the multiplexed control line signals at reception side.

Abstract: Narrowband based telephony services and associated value added services are provided transparently in a network providing ATM switching and no STM switching is required in an ATM network (625) to which units (601, 603) requiring such services are connected. This is obtained by means of, when a call enters the ATM network (625), first finding the output port (619) from the ATM network (625), then returning the address of that port to the entry port (617) and thereafter ATM switch the connection directly through the ATM network (625). Hereby bandwidth resources are more efficiently used since all switching is done by ATM regardless of application. Heavy investments in providing intelligent services support by existing systems can be reused in an efficient way and thus reduce time to market for the introduction of the value added services.

Abstract: To provide a transmitter/receiver and a method for a multiplexing transmission and reception of transmission signals of Gigabit Ethernet, without needing a great buffer memory, nor processes for adding channel identification numbers to frames or for removal, at a multiplexed signal transmitter in which data signals input from a plurality of channels of Gigabit Ethernet are multiplexed to be transmitted, a particular 10-bit data word is transmitted before transmission of a data input from a particular channel, and at a multiplexed signal receiver, the particular channel is identified by the 10-bit data word to be present or not.

Abstract: A digital-to-phase or digital-to-time-shift converter (100) includes a delay line (106), a multiplexor (108) and synchronization circuit (110). In the converter (100) the clock edges of a reference signal are shifted in response to the value of a multi-bit digital word, IN (104). The synchronization circuit (110) gates the output of the multiplexor (108) such that a pulse appears at the synchronization circuit's (110) output port (114) only when the circuit is gated by a signal at input TRIG (112). The synchronization circuit (110) creates a time aperture for the multiplexor output.

Abstract: The present invention discloses a system which comprises two endpoints (1, 2) communicating with each other by means of a packet-switched network. The endpoints (1, 2) use adaptation algorithms for estimating jitter from packet arrival times and for modifying silence period lengths according to the latest estimate. According to the present invention, the endpoints (1, 2) are able to measure a response time (?) at a certain point of time and use it as a parameter in the adaptation algorithms.

Abstract: A method of communication between communications networks in which different communication protocols are used and which are connected to each other by way of at least one intermediate node. In order to communicate easily between the networks, both the destination node and the start node are prompted to use a common communication protocol by the intermediate node in that this node transmits messages to the destination node and the start node upon reading destination node information from a data collection.

Abstract: A mobile station is coupled to a first base station via a first wireless connection while in the zone of the first base station zone. Through the first base station and in conjunction with a PPP session manager, the PPP session manager establishes a first link of a PPP session to a remote server across a data network having mobile station handoff capability. When moving into the zone of a second base station and in conjunction with the PPP session manager, the PPP session manager creates a second link of the PPP session. The first and second links take different paths through the data network. The PPP session manager releases the first link while preserving the PPP session.

Abstract: A system for use in a bi-directional path switched ring network for detecting a failed optical path and establishing a protection path so as to allow signals from the failed optical path to be re-routed via the protection path is provided. According to one aspect of the system, upon detecting a failure relating to an optical path, the destination node generates a connection request message for transmission to the source node. The connection request message is passed to the source node via one or more intermediate nodes, if any. Each intermediate node examines the connection request message accordingly reserves the requisite wavelength from the protection capacity so as to allow signals from the failed optical path to be re-routed. Upon receiving the connection request message, the source node readies its switching equipment to re-route signals from the failed optical path and generates an acknowledgment message and propagates it back to the destination node via the intermediate nodes.

Abstract: A system and method for low latency switching of data packets in a network switch. A network switch may include multiple input ports, multiple output ports, and a shared random access memory coupled to the input ports and output ports by data transport logic. Under normal operation, the data transport logic stores packet data into the memory. Later, the packet data is read from the memory and output to a destination output port. To reduce latency when the switch is not congested, the switching logic may be configured to perform a cut-through operation by routing packets directly from input ports to output ports without storing any portion of the packet in the memory. Alternatively, the switch may begin forwarding the stored packet data to the output port before the entire packet has been received or stored in the memory.

Abstract: A digital switching system includes a multiplexer for multiplexing time slots from a plurality of circuits, a switching memory for storing and switching the multiplexed data for one frame period, switching control equipment for directing the interchange of the time slots stored in the switching memory in response to a switching request from an upper layer controller in a network, and a demultiplexer for demultiplexing into the plurality of circuits the time slot data as read out using address data supplied from the switching control equipment. The switching control equipment includes a control memory unit for writing connection information from the upper layer controller to either a first or a second control memory, and sequentially reading out the stored connection information in read-out order for the switching memory, and a selection unit for selecting read-out from either the first or the second control memory in response to the switching request.

Abstract: A method for determining the validity of an n-dimensional policy table in a router. The router may include a processor, a memory (e.g. ROM, flash memory, non-volatile memory, hard disk, etc.), and two or more policy rules stored in the memory. Each policy rule may have one or more dimensions (or parameters), designated generally by the symbol n. In accord with the method, the processor may make a determination whether any particular policy rule in the table intersects any subsequent policy rule in the table in every dimension n. If no rules in the table intersect in every dimension n, then the policy table is valid, and the router may operate normally.

Abstract: A method and apparatus for implementing virtual wire signaling is described. It includes an apparatus including a first component, a bus coupled to the first component, the bus to transmit packets of data, and a second component coupled to the bus, messages passed between the first component and the second component through packets transmitted on the bus.

Abstract: Multiple streams of bits are received. One or more bits are selected from a stream of bits based, at least in part, on a space control register value and a time control register value. In one embodiment, a time control register stores a value indicating a selected bit from a sequence of bits, a counter counts bits in the sequence of bits from a predetermined bit, and a comparator is coupled to the time control register and to the counter to generate a load signal when a value stored in the time control register and a value provided by the counter are equal. The load signal causes the latch to load a value output by the multiplexer.

Abstract: A system and method are disclosed for determining when to set up or tear down such a temporary transit path so that temporary transit paths are set up when they are needed and torn down when they are no longer needed. A temporary transit path is set up when the bit rate exceeds a first threshold. The temporary transit path is torn down when the bit rate is less than a second threshold. The temporary transit path is set up or torn down between a source station's router and a next hop router. The temporary transit path is set up within a subnetwork that includes the source station, the next hop router, and an intermediate router that is interconnected by a plurality of permanent transit paths to the source station and the next hop router. In one embodiment, a method for creating a temporary path for data packet transmission in the subnetwork is disclosed. Transmission of the data packets is initiated over the permanent transit paths that are coupled between the source station and the next hop router.