Abstract: Domains are defined to incorporate a subnet including a plurality of base stations and routers. Base stations are used by mobile devices to attach to the wired portion of a packet-based network, such as the Internet, and exchange packets thereover with a correspondent node. Local mobility between domain base stations is provided by including and updating routing table entries at domain routers and base stations for forwarding packets having a mobile device's address as a destination address to the mobile device. Packets are delivered to the mobile device regardless of the domain base station to which the mobile device is attached. When a mobile device is attached to a base station included within a foreign domain, a care-of address is assigned, and packets are tunneled for delivery of packets to the mobile device. Only one care-of address is required per mobile device per foreign domain.

Abstract: A system and method are provided for managing information concerning a network flow comprising packets sent from a source entity to a destination entity served by a network interface. A network flow is established for each datagram sent from the source entity to the destination entity. A flow key, identifying the source and destination entities, is stored in a data structure along with information concerning validity of the flow, sequence of data in the flow datagram and how recently the flow was active. Once a flow is established, it is updated each time a packet containing data from the flow's datagram is received. When such a packet is received, an operation code is generated for identifying whether the packet is suitable for a particular network interface function. An operation code may, for example, indicate that a packet contains data to be re-assembled with other data from the same flow. Another operation code may indicate that a packet is not suitable for data re-assembly.

Abstract: Method and apparatus are disclosed for an optoelectronic network interface device allowing reconfiguration of ports in a Local Area Network (LAN). More particularly, the optoelectronic interface device is integrated to include optical ports for communicating with a network, electronic circuits for providing an interface to end-users and a controllable electronic switch between the optical ports and electronic circuits. In response to a control signal, the switch dynamically reconfigures the connection between selected optical ports and selected electronic circuits.

Abstract: Nodes notify each other of the availability situation of links, whereby the link availability situation is reflected in the network topology information held by each node. The designated routing information of a packet which arrives at a local node for subsequent transfer is updated on the basis of the topology of a network from which the following have been removed: any nodes which a packet arriving at the local node for subsequent transfer has already passed; any links directly connected to such nodes; and any congested or faulty links.

Abstract: An asynchronous transfer mode (ATM) switch is configured to automatically generate Operations, Administration and Management (OAM) cells for a loopback test at a first connection whenever the first connection is not receiving user data traffic. The ATM switch may include a switch management module which generates the OAM cells that are transmitted from the first connection whenever a control processor initiates the loopback test.

Abstract: An optical line termination in an asynchronous transmission mode includes a downstream frame processing unit for receiving and churning an asynchronous mode cell to generate a downstream frame, and converting a parallel data of the downstream frame into a serial data thereof, a wavelength division multiplexing unit for performing an electro/optical conversion of the serial data of the downstream frame and performing a wavelength division multiplexing thereof, an upstream frame processing unit for extracting data from the wavelength division multiplexing unit, searching an overhead field, delineating a slot boundary, and processing a PLOAM cell and a divided slot separately, a control signal generation unit for performing a MAC protocol and generating variables and timing signals used for the downstream frame processing unit and the upstream frame processing unit, and a control unit for controlling the downstream frame processing unit and the upstream frame processing unit by using the variables and the timing

Abstract: A method, system and article of manufacture to prevent signaling congestion in a connection-oriented network node in situations where a plurality of network-attached data terminal equipments (source DTEs) concurrently request a connection to at least one network-attached data terminal equipment (destination DTE), each of the source DTEs sending call setup messages (CSMs) through the network node to the at least one destination DTE. The CSMs having to be processed by the network to establish the connections requested.

Abstract: A circuit comprising a plurality of communication devices each configured to receive and transmit one or more data packets in response to one or more control signals and a control circuit configured to generate the one or more control signals in response to the one or more data packets.

Abstract: A method for transmitting data packets having a heading followed by a data field. The data of the field is transmitted by groups of symbols. According to the OFDM technique, subcarriers modulated by the groups are generated. A frequency modulation of a carrier signal delivered by a linear ramp generator is produced with a set of modulated subcarriers. When the signal is received, mixing with a linear ramp results in subcarriers which are separated and then demodulated for supplying data. This is useful for transmitting data packets particularly in wide band networks.

Abstract: A method for testing a data path of a server operably connected between at least one peripheral device and at least one client device via a network includes independently testing one of a peripheral interface portion of the data path and a network interface portion of the data path, and generating a status report indicating the result of the test.

Abstract: A modular multi-service telecommunication access device includes a controller card and card slots for six peripheral cards and a power supply. Any of several types of peripheral cards can be inserted into the six card slots. A card present/protocol scheme allows an inserted card to recognize its address and communicate same as well as its communication protocol to the controller card via a PCM highway. The controller card sends both signaling information and management information to the peripheral cards via another PCM highway. A unique communication protocol allows for both real time signaling information and non-real time management information to be sent on the same channel. A microprocessor on the controller card includes an algorithm for managing messages to the various peripheral cards in the various card slots. A unique tributary addressing scheme allows for a simplified address used by external users to be converted to a more detailed internal address.

Abstract: An ATM cell multiplexer is arranged so that in the up direction from the terminal equipment to the ATM switchboard cells from a cell terminal portion in CLAD units are held in a cell holding portion through a Utopia Level 2 interface under the control of a communication controller in the CLAD units, and an ATM bus scheduler makes the cell holding portion transmit the cells to an ATM bus by assigning a transmission right for every cell holding portion of the CLAD units in accordance with a preset schedule table based on at least one of predetermined service categories and a traffic control corresponding to a traffic quantity, while in the down direction from the ATM switchboard to the terminal equipment the cells are broadcast from the ATM bus to the cell holding portion of each CLAD unit for a cell transfer and the communication controller makes the cell holding portion transfer the cells to the cell terminal portion through the Utopia Level 2 interface to decide whether or not the cells are addressed to itse

Abstract: A flow control process for a switching system having at least one switch core connected through serial communication links to remote and distributed Protocol Adapters or Protocol Engines through Switch Core Access Layer (SCAL) elements. For each input port i, the SCAL element contains a receive Protocol Interface corresponding to the adapter assigned to the input port i and a first serializer for providing attachment to the switch core by means of a first serial communication link. When the cells are received in the switch core, they are deserialized by means of a first deserializer. At each output port, the cells are serialized again by means of a second serializer and then transmitted via a second serial communication link, to the appropriate SCAL. The SCAL contains a second deserializer and a transmit Protocol Interface circuit for permitting attachment of the Protocol Adapter.

Abstract: A switching system having at least two switch fabrics. Each fabric has a switch core and a set of SCAL (Switch Core Access Layer) receive and transmit elements. The switch cores are preferably located in the same physical area but the SCALs may be distributed in different physical areas. Port Adapters distributed at different physical areas are connected to the switch fabrics via a particular SCAL element so that each switch core can receive cells from any port adapter and conversely any port adapter may receive data from either switch core. Control logic assigns a particular switch core to one port adapter for normal operations while reserving the other switch core for use when the first core is out of service. Each switch core has a mask mechanism which uses the value in a mask register to alter a bitmap value which controls the routing process. The mask registers in the two switch cores are loaded with complementary values.

Abstract: An architecture for capture and generation, and a set of methods for characterization, prediction, and classification of traffic in packet networks are disclosed. The architecture consists of a device that stores packet timing information and processes the data so that characterization, prediction, and classification algorithms can perform operations in real-time. A methodology is disclosed for real-time traffic analysis, characterization, prediction, and classification in packet networks. The methodology is based on the simultaneous aggregation of packet arrival times at different times scales. The traffic is represented at the synchronous carrier level by the arrival or non-arrival of a packet. The invention does not require knowledge about the information source, nor needs to decode the information contents of the packets. Only the arrival timing information is required. The invention provides a characterization of the traffic on packet networks suitable for a real-time implementation.

Abstract: There is disclosed a method and a system for multiplexing data from a plurality of user data sources across an ATM adaption layer type-2 connection, in which a multiplexed trunk group extends across a plurality of common part sub-layer protocol data unit (CSU-PDU) mini-cells, and across a plurality of ATM cells. Large trunk groups are assembled by use of a single bit continuation indicator in the service specific convergence sub-layer header (SSCS) of successive CPS-PDU mini-cells. A packet payload type field (PPT) of the common part sub-layer (CPS)/service specific convergence sub-layer (SSCS) is used to indicate timing of changes in number of user data sources in a trunk group and provides for robust error recovery on loss of a single CPS-PDU mini-cell.

Abstract: There is provided a transmission system which realizes more flexible resource allocation. A resource management means 12, upon receipt of a resource allocation request including a minimum bandwidth and a maximum bandwidth, reduces allocated resources stored in an allocated-resource request table 13 to the corresponding minimum bandwidths. As such, the request is accepted with higher probability. When releasing an allocated resource, the resource management means 12 increases the allocated-resources of the allocated-resource requests to bandwidths within a range of the corresponding maximum bandwidths. Accordingly, the resources are utilized more effectively. When releasing the resource, the resource management means 12 notifies, by broadcast, all the communication apparatuses that free resources are increased. Thus, for the communication apparatus whose request has been rejected, the resource is allocatable.

Abstract: The invention relates to a method for the transmission of an asynchronous data stream, containing useful data, via a synchronous data bus which is arranged to transmit data frames in time multiplex. The invention is characterized in that the asynchronous data stream is converted into a synchronous, continuous data stream by means of a converter circuit, that within the data frames a selectable number of storage locations is provided for the useful data of the asynchronous data stream, that a variable number of useful data can be assigned to the individual data frames by the converter circuit and in dependence on the speed of the asynchronous data stream, and that protocol data is assigned to the individual data frames by means of the converter circuit, each time in a predetermined position within the data frames, which protocol data contains information as regards the number of useful data present in the relevant data frame.

Abstract: A method and apparatus for the restart communication between network elements are described. In one embodiment, a method for restarting communication between a first network element and a second network element in a network comprises transmitting a modified hello packet to the second network element. The modified hello packet includes a time value that is greater than a time value of a hello packet that was transmitted to the second network element prior to International-System-International-System (IS-IS) network communications in the first network element becoming non-operational. The method also including updating routing information within the first network element through transmission of Complete Sequence Number Packets of the IS-IS standard to the second network element, independent of tearing down a communication link between the first network element and the second network element after IS-IS network communications in the first network element have become non-operational.

Abstract: A method and network element for feedback control for adjusting a rate of message transmission over a connection in a network is provided. The connection comprises a source and destination linked by forward and backward message paths. The source has instructions for setting a message transmission rate for the connection provided by feedback messages received, each containing an explicit rate of transmission. The method comprises steps: receiving feedback messages from the backward path; extracting an explicit rate being carried by each feedback message received; storing each feedback message received in a queue; retrieving a stored feedback message and, substantially when it is transmitted, marking it with an explicit rate determined from an extracted explicit rate pertaining to another message received more recently and a rate determined from a state of congestion of the network element; and externally transmitting the feedback message over the backward message path once so marked.