Abstract: An example embodiment of the present invention is a method of managing network communications layers on a network. The example embodiment (i) selects nodes in a network normally configured with server layer resources (e.g., SONET/SDH) to support client communications on a communications path between source nodes and destination nodes and (ii) instantiates client layer resources (e.g., Ethernet or IP) to support communications at branch nodes among the selected nodes at which communications paths from a common source node split to take different paths toward different destination nodes or at which communications paths toward a common destination node merge from different source nodes. Dynamic configuration of client layer resources is thus provided, and the given node may operate in an autonomous manner, instantiating client layer resources on an as needed basis.

Abstract: A method and apparatus for determining a communication path over a network are provided. The method involves generating a spanning tree having connection devices over a network as vertices and having links among the connection devices as edges; allotting predetermined vertex information to each vertex on the spanning tree; detecting all circuits having a plurality of communication paths among the connection devices over the network corresponding to the spanning tree; and applying rapid ring spanning tree protocol (RRSTP) to links corresponding to the detected circuits and applying rapid spanning tree protocol (RSTP) to links not corresponding to the detected circuits.

Abstract: A method for traffic engineering of connectionless virtual private network (VPN) services. The method comprises receiving physical connectivity data for a connectionless VPN including service nodes and links between the service nodes. One or more of the service nodes are also edge nodes. Logical connectivity data for the edge nodes is received. A restricted topology is created in response to the physical connectivity data and to the logical connectivity data. The restricted topology includes a single path between each pair of the edge nodes and each path includes a plurality of the service nodes and one or more of the links. A bandwidth requirement for each link in the restricted topology is calculated. The bandwidth requirement is reserved on each link in the restricted topology. The method further comprises directing routing software to force a packet received from an edge node through one of the paths in the restricted topology.

Abstract: The invention relates to a method and apparatus for disseminating Virtual Local Area Network (VLAN) membership information across computer networks defining multiple spanning trees. An intermediate network device configured in accordance with the invention includes a plurality of ports and a plurality of spanning tree engines each associated with one or more VLAN designations defined within the network. The spanning tree engines transition the ports among a plurality of port states, including a forwarding state and a blocked state. For each port, a separate Generic Attribute Registration Protocol (GARP) participant is also established and each GARP participant includes a multiple spanning tree (MST) GARP VLAN Registration Protocol (MST-GVRP) application component and an associated GARP Information Declaration (GID) component.

Abstract: A communications system in which a first node is connected to a plurality of second nodes for controlling the operation of the second nodes. The plurality of second nodes is arranged in one or more logical interconnects, the topology of the one or more logical interconnects being distinct from the topology of the physical interconnection of the nodes. Each second node sends status messages to its logical successor node and monitors the status messages received from its logical predecessor node for determining the status thereof.

Abstract: A method and apparatus relating to the behavior of border nodes within a high performance serial bus system is disclosed. A method is disclosed for determining a path to a senior border during the Self-ID process in a full-duplex communications system having at least one border node comprising the acts of: marking the border node as the senior border; determining whether the border node has received a Self-ID packet that does not contain a Speed Code on a parent beta port of the border node; marking the port on said border node as the path to the senior border node if the border node has received a Self-ID packet that does not contain a Speed Code on a parent beta port of the border node; and canceling the border node's own status as a senior border node.

Abstract: A method relating to the behavior of border nodes within a high performance serial bus system is disclosed. A method is disclosed for determining a path to a senior border node comprising the acts of: determining whether a B PHY has received a Self-ID packet without a Speed Code on at least one port; and marking the at least one port on the B PHY that was last to receive a Self-ID packet without a Speed Code as the path to the senior border node and canceling by the B PHY of any other ports within the node that have been marked as the path to the senior border node if the B PHY has received a Self-ID packet without a Speed Code on the at least one port.

Abstract: A content addressable merged queue (camQ) architecture for high-speed switch fabrics reduces the memory requirement for crossbar switch input and output queues using memory cells and age tag comparators. CamQ emulates VOQ FIFO for each supporting priority, eliminating HOL blocking. Multiple QoS levels are supported cost effectively at higher traffic bandwidth limits. Content addressable memory (CAM) cells store payload destinations, which can be addressed by cell priorities. Once a priority for QoS is decided, all the cells with the selected priority in the payload can make connection requests to destination ports directly through the CAM structure. An age tag is assigned to incoming cells and fast age tag comparators provide FCFS features by selecting the oldest cell. Small memory sizes prevent the bottlenecking in ingress and egress queues. A CIOQ crossbar has a fast switching speed, emulating a FIFO output queue switch. Age and priority are interleaved to schedule switching.

Abstract: A technique is presented for compressing data which leverages the frequency of an escape symbol for better compression. The prefix of a data string is evaluated and the probability of all characters that might succeed it is predicted in tabular form. Symbols are designated “Hit” or “Miss” based upon whether they are in the table. A binary tree is generated by partitioning nodes into Zero and One groups based on a single bit value. A partition bit is chosen to maximize the difference of probability sums of Hit symbols in Zero and One groups, with exceptions for partitions having non Hit symbols in one of the groups. A probability value is assigned to each branch, based on the probabilities of Hit and Miss symbols. Encoding or decoding a symbol is facilitated by encoding or decoding the branch probabilities on the shortest path from the root to the leaf node containing the symbol using arithmetic encoding or decoding method.

Abstract: A first transceiver (4, 30) can position itself by forming an ad hoc network (20) of transceivers which assist the first transceiver in acquiring its position. A dedicated infrastructure such as GPS satellites is not required. The first transceiver (4, 30), once it has acquired its position, can be involved in a network (20) by another transceiver (32, 34, 36, 38, 40) to assist in the positioning of that transceiver. The acquisition of the position may involve factors such as the trustworthiness of the transceivers in the network and/or the positions of transceivers with which the first transceiver cannot directly communicate.

Abstract: The present invention relates to a method for optimization of demands in a packet switched communication network, especially, though not exclusively, for the optimization of demands in a Multi Protocol Label Switching (MPLS) packet switched communication network. The present invention provides a method to enable network nodes, such as routers to be clustered into components, with the components organised in a hierarchical fashion, and with the network “core” at the root of this hierarchy. Demands that originate or terminate at components outside the core, but that traverse the core, are temporarily replaced by demands that originate and terminate within the core component. Having optimized the resulting set of demands it is then shown how to use the solution to satisfy the original demands. Multi-access networks cause some complications, and these are taken into account.

Abstract: Disclosed is a method, apparatus and computer-readable medium for selecting a root bridge when a spanning tree is configured in an Ethernet network including a plurality of legacy switches and a plurality of synchronous switches. The method comprises the steps of providing in advance identification information in a configuration BPDU message of the synchronous switch, the identification information representing that a corresponding switch is an AV switch, broadcasting configuration BPDU messages by the legacy switches and the synchronous switches; and receiving configuration BPDU messages by the synchronous switch from other switches, confirming bridge priorities according to the synchronous switches through the received configuration BPDU message and the identification information to select a synchronous root bridge, receiving configuration BPDU messages by the legacy switch from other switches, and confirming bridge priorities through the received configuration BPDU messages to select a legacy root bridge.

Abstract: The present invention refers to a gateway (MGW1) in a telecommunication system (TS1) enabling connections to be effectively established between various networks (N1, N2, N3) in the telecommunication system. The gateway comprises resources from different nodes (RNC1, MSC1, IP1, VX1) of the various networks. Servers (S1-S6) from the networks are connected to the gateway (MGW1) and co-utilize the resources, which contributes to the effective utilization of the resources. This effective utilization of the resources is supported by the resources being divided into resource groups. Specific ones of these resource groups can be utilized by solely each one of the servers. Consequently, important services such as alarm services and security services can always reach the necessary resources in the gateway. Other resource groups can be co-utilized by only a small number of the servers while additional resource groups may be co-utilized by all of the servers (S1-6).

Abstract: A wireless multi-node communication network which includes a coordinator, and a plurality of vehicle nodes which are configured to communicate information back and forth with said coordinator. The system may include a plurality of clusters, each of which comprises a plurality of devices such as sensors. One of the devices of each cluster is configured to receive information from the other devices in the cluster, and transmit information to the coordinator. The coordinator not only receives information about the network, but may also be configured to route the information to other networks. The network could be disposed on a tractor-trailer, wherein the devices comprise different sensors, such as pressure sensors, temperature sensors, voltage sensors and switch controls, all of which are located in areas relatively close to each other.

Abstract: Methods and apparatus for bridging network protocols are disclosed. A protocol bridge may be used to function as a target for a network processor while performing a target mode operation, while functioning as an initiator on behalf of the network processor while performing an initiator mode operation. In one embodiment, the protocol bridge determines the mode of operation based on information in a received frame's header. In another embodiment, the protocol bridge couples a Fiber Channel device to a storage processor on a packet-over-SONET network.

Abstract: Methods and apparatus provide PCI Express support on a programmable device. A device includes a hard-coded transceiver that supports functionality associated with the PCI Express physical layer and link layer. The hard-coded transceiver can also support part of the PCI Express transaction layer. Soft-coded logic is used to support higher layer functionality including a portion of the transaction layer to allow custom configuration of PCI Express features such as virtual channels, buffers, prioritization, and quality of service characteristics. The hybrid solution reduces logic resource cost and provides an effective custom configurable solution.

Abstract: A method for conveying a security context, including creating and assigning a virtual address to a client process, issuing a first Internet Protocol version compliant packet wherein the first Internet Protocol version compliant packet comprises a security context, prepending an issued packet with a second Internet Protocol version header producing a second Internet Protocol version compliant packet, forwarding the second Internet Protocol version compliant packet to a recipient, stripping away the second Internet Protocol version compliant header from the second Internet Protocol version compliant packet producing a stripped packet at the recipient, decrypting and authenticating the stripped packet using a particular method as indicated by the security context producing a decrypted and authenticated packet, and routing the decrypted and authenticated packet to a recipient process using the virtual address.

Abstract: A process for merging and using the Mediation Device Protocol with a network layer protocol. Under the merged protocol, each device joining a network enters into two stages: the Set-Up Stage and the Normal Operational Stage. During the Set-Up Stage, the device identifies its neighbors, builds a neighborhood list, obtains a Logical ID, and picks a parent node in the network. After the Set-Up Stage is complete, the device enters the Normal Operational Stage where it will send/receive control and data messages, invite and help new nodes to join the network, recover from broken links or topology changes, and other normal network operations.

Abstract: A route update method includes: storing information on route insertion sequence by each routing protocol in respective entries in a routing table; performing a prefix search according to the stored route insertion sequence upon a restart of a routing module, and updating a corresponding routing entry upon a prefix matching occurring as a result of the prefix search, and performing a search according to a general Trie structure upon a prefix matching failure to succeed occurring as a result of the prefix search. Accordingly, the route search time is reduced upon a route update.

Abstract: A client-server based system for providing location related information and services to mobile users is disclosed. A plurality of servers, wherein a server is a provider of information and services related to a specific predefined geographical coverage area, operate in a tree-shaped network. An operating mobile client, preferably operating in a mobile phone or PAD of a mobile user, establishes upon connection to the network an association, based on client location information, with one server at a time. A server association can be transferred from one server to another on an existing network connection as the user relocates from one server coverage area to another, and a user profile stored with the client or a special user profile server is applied to the standard user interface in the current server to provide the client with a personal user interface adapted at any time to the requirements of the user and to the information and/or services available at the current server.

Abstract: A method for restoring traffic in a network. The network includes plural distinct nodes interconnected by plural distinct spans, each span having working links and spare links. Each node has a digital cross-connect switch for making and breaking connections between adjacent spans forming span pairs at a node. Cross-connections between spare links in adjacent spans are made such that sets of successive nodes through which the adjacent spans form span paths form closed paths. A method of finding and construction closed paths is described in which statelets are broadcast through the network. In a preferred method of implementation of the method, the statelet broadcast occurs not in response to a network failure, but across the entire network before any particular span failure and may be carried out during normal network operations as a continual re-configuration of the network.

Abstract: A mobile router is configured for attaching to a selected router in a mobile network based on identifying a network topology model of the mobile network from received router advertisement messages that include tree information option fields specifying attributes of the network topology model. The mobile router selects which router advertisement originator to attach to based on correlating the attributes of the router advertisement originators relative to identified priorities, and orders the router advertisement originators within a default router list based on the identified priorities.

Abstract: A mobile router is configured for attaching to a selected router in a clustered network (e.g., a mobile ad hoc network) based on identifying a network topology model of the clustered network from received router advertisement messages that include tree information option fields specifying attributes of the network topology model. The mobile router selects which router advertisement originator to attach to based on correlating the attributes of the router advertisement originators relative to identified priorities, and orders the router advertisement originators within a default router list based on the identified priorities. If the mobile router detects a router from a second clustered network, the mobile router advertises to the attachment router that the second clustered network is reachable, enabling the two clustered networks to communicate using a point-to-point link between the respective attachment routers.

Abstract: In flow control apparatus formed of a network of switching hubs in a hierarchy configuration for performing data packet transfer within each of a plurality of respectively separate groups of terminals, based on use of group identifiers contained in the data packets, occurrence of congestion of the output section of a port of a switching hub is judged respectively separately for each of the terminal groups, and one or more congestion notification packets for effecting a pause in data packet transmission are generated and transmitted from that switching hub, directed only to one or more terminals of a group relating to the congestion. As a result, the effects of port congestion and of congestion control operations are limited to the terminal group concerned.

Abstract: A mobile ad hoc network may be established between a plurality of devices that have common contacts on their contact lists. The contact lists may be conventional contacts stored in a list of contacts on a scheduling and information management or other software packages in one embodiment. Communications with various devices is limited to those devices listed on the list of contacts. Modification of those lists of contacts is controlled on a password-protected basis in one embodiment. Thus, a parent, for example, may limit the ability of child users to contact or be contacted by and communicate with unauthorized persons.

Abstract: A method for providing communications systems and network connection services is disclosed. Via a portal, user requirements data are entered, which are determinative of a configuration of the communications system. The user requirements data are translated into configuration data, which is stored in a storage location in electronic communication with the portal. The configuration data is provided to a manufacturing agent, which manufactures the communications system. The step of manufacturing the communications system includes loading the configuration data into the communications system, and the communications system operates based on the configuration data. The communications system is provided to a customer, and the communications system is operative to provide voice and data communications to a plurality of users in accordance with the configuration data.

Abstract: Prefix searches for directing internet data packets are performed in a prefix search integrated circuit. The integrated circuit includes an array of search engines, each of which accesses a prefix search tree data structure to process a prefix search. An SDRAM is dedicated to each search engine, and SDRAMs share address and control pins to plural search engines on the IC chip. Internal nodes of the tree data structure are duplicated across banks of the SDRAMs to increase bandwidth, and leaf nodes are stored across the SDRAM banks to reduce storage requirements. Within each search engine, data stored in a data register from an SDRAM is compared to a prefix search key stored in a key register. Based on that comparison, an address is calculated to access further tree structure data from the SDRAM. Packet descriptors containing search keys are forwarded to the search engines from an input queue and the search results are forwarded to an output queue, the same packet order being maintained in the two queues.

Abstract: A method and apparatus for intelligent packet forwarding utilizing virtual ports defined by a grouping of one or more STS-1s allocated to source and destination I/O devices (client) connected to an NxSTS-1 SONET network. A data flow path for transporting the client data is established from one virtual port at the source port to another virtual port at the destination port. The data flow path is established by notifying each of the ports of the data flow path and providing to the source port an address identifying the destination port and providing to the destination port an address identifying the source port.

Abstract: The invention is directed to techniques for maintaining a map of node relationships for a network of nodes (e.g., network of computers). In one example, the map of node relationships represents relationships overlaying and typically different from the network of physical connections among the nodes. Each child node periodically checks in with its parent nodes, and the parent nodes can thus determine when a child node has terminated a relationship with the parent or created a new relationship with a new parent. Changes in relationships propagate upward through the network of nodes so that each node maintains a map of the relationships among the descendants of that node. A root node receives the propagated change relationship information and maintains a map of the entire network and valid pathways through the network.

Abstract: A routing control system comprising a spanning tree producing portion provided in a master node of a radio access network. The spanning tree producing portion produces a spanning tree of the network whenever it receives connection information sent from slave nodes of the network. The spanning tree is delivered to each slave node. A memorizing portion is provided in each of the nodes and memorizes the spanning tree as a routing table. A health check portion is provided in each of the nodes and transmits the connection information to the spanning tree producing portion when topology change of the network is detected. The said health check portion updates the routing table in cooperation with those of adjacent nodes.

Abstract: Methods and arrangements for repositioning at least one node in a distributed network. Upon detection of a failed node in the network, subscription information relating to each direct child node of the failed node is retained at each direct child node.

Abstract: A method for optimizing a communications network such as a wireless telecommunications network, having central switch nodes and intermediate base station transport nodes, via a non-hierarchical clustering technique is provided. At least one of the central switch nodes may be fixed in location, the remaining central switch nodes being moveable. After an initial network configuration is obtained, distances from each base station to each central switch node are calculated and the nearest central switch node to each base station is determined. Each base station is assigned to its nearest central switch node. Thereafter, the moveable central switch nodes are relocated to the location minimizing the sum of the distances between each base station assigned to the switch and the switch.

Abstract: A method of expandable network slot addressing to provide topological information for a network. The method includes providing a platform having addressable slots for data communication. A first tier device is located in one of the slots in the platform. At least one second tier device is connected to the first tier device. An extendable address is assigned to each of the first and second tier devices, with each address including a slot address segment which indicates which slot each of the devices resides in or is connected to at the modular platform, a depth segment which indicates a layer in the topology at which the device is located and a number of address bytes that are present, and an address byte segment which indicates where in the topology the device is located and provides each of the devices with a unique address so that each of the devices attached to the platform can be addressed and its topological position can be inferred from the address.

Abstract: A system and method prevents the formation of loops that are not detected by the Spanning Tree Protocol (STP). An intermediate network device preferably includes a plurality of ports for receiving and forwarding network messages and a STP engine in communicating relationship with the ports. The STP engine transitions the ports among a plurality of spanning tree port states, including a discarding state, a learning state and a forwarding state. The device further includes a loop guard engine that is in communicating relationship with the STP engine and the ports. The loop guard engine monitors the receipt of configuration bridge protocol data unit (BPDU) messages by the ports. If a given port stops receiving BPDU messages, the loop guard engine prevents the STP engine from transitioning the given port to the forwarding state. Instead, the loop guard engine preferably causes the port to transition to a new state in which networks messages are explicitly blocked from being forwarded or received.

Abstract: Various aspects of an interactive multimedia system and associated methods. In general, the multimedia system employs central and peripheral hubs that function to provide services to a plurality of clients of a call manager server, or manager subsystem. The hubs and subsystem cooperate to serve requests originating in the plurality of clients. The client-server-client architecture allows for distributed processing and resource management. Redundant connections between the various network subsystems and hubs provide survivability. Each subsystem or hub is provided with the ability to initialize or recover from systemic errors, thereby distributing initialization and recovery. Certain of the distributed resources are capable of being managed from other subsystems, thereby allowing sharing of the resources. An open numbering plan allows efficient call treatment of dialed numbers. Call processing is sharable between multiple manager subsystems.

Abstract: Systems and methods provide very fast protection switching while leaving selected traffic unprotected. When a link fails, only certain pre-selected paths are rerouted at the point of failure. Other traffic is left unprotected or protected at another layer. Signaling of the failure and the rerouting is performed for the link as a whole rather than for the individual paths. Signaling occurs at a first layer of a digital transmission hierarchy while path rerouting switching occurs at a second hierarchical layer above the first layer. In certain implementations, K1/K2 bytes are used in signaling at the optical line layer (OC-n), while only protected High-Order paths (STS) and Low-Order paths (VT) are protected by the protection switch.

Abstract: Methods and apparatus are provided for generating a set of restrictive costs associated with directional paths between selected nodes in a group of nodes of a network system wherein each node in the group is connected by a link to at least one other node in the group, and each link has a pair of directional costs associated therewith such that each link can be considered as a pair of oppositely-directed, unidirectional links each of which extends from a source node to a destination node and has a said directional cost associated therewith. The method allows asymmetric costs, rather than merely symmetric costs, to be considered, and can be applied, for example, to generate the transition matrix for a PNNI peer group.

Abstract: Techniques are disclosed for improved monitoring and analysis of VoIP communications, multimedia communications or other types of network traffic in a network-based communication system. In accordance with one aspect of the invention, endpoint devices of the network-based communication system are configurable so as to collectively implement a distributed monitoring and analysis system which does not require a centralized testing server or other centralized controller. Distributed test units associated with the endpoint devices may be utilized in implementing the distributed monitoring and analysis system, and are preferably configured to support a web-based user interface providing access to measurement data. The endpoint devices may be advantageously organized into a hierarchy comprising a plurality of zones, with each of the endpoint devices belonging to at least one zone.

Abstract: A method of synchronizing nodes of a telecommunication network in which a master node is coupled to a Primary Reference Clock (PRC) and a plurality of slave nodes are each arranged to synchronize their internal clocks to the PRC using data received on incoming data links. The method includes propagating Synchronization Status Messages through the network from the master node, with each node through which a message passes incorporating into the message its own identity, thereby generating in each message a node path which has been followed by the message. For each incoming link of each node, the path or path length of a Synchronization Status Message received on that link is registered as an attribute for that link.

Abstract: A method and apparatus for performing classification in a hierarchical classification system performing caching are described. In one embodiment, the method comprises walking a classification tree in the hierarchical classification system to determine whether an incoming flow matches a class in the classification tree, and performing a lookup on a cache storing a data structure of multiple classes of one classification type to compare the incoming flow with multiple classes at the same time to determine whether the incoming flow matches one of the classes.

Abstract: A method for performing end-to-end “tree-based ordered multicasting” (TOM) which ensures collective integrity and consistency of distributed operations, and which is applicable to distributed multiparty collaboration and other multipoint applications. The TOM protocol performs cascaded total ordering of messages among on-tree hosts en route from senders to receivers, and does not require the building of a separate propagation graph to compute ordering information. TOM elects sequencer nodes dynamically based on address extensions of the multicast tree. Message ordering is performed by multicasting a message from each source node to receivers, unicasting a control message from a source node across a primary node to an ordering node for the designated multicast group or transmission in the tree, determining a binding sequence number for the message and a multicast to the receiver group, and delivering messages at end hosts according to the agreed-upon sequence numbers.

Abstract: Bridges (10, 12, 14) are used to interconnect local area networks transparently. In the IEEE 802.1D standard for bridges, a spanning tree is built among the bridges for loop-free frame forwarding (FIG. 10). Although this approach is simple, it does not support all-pair shortest paths. A novel bridge protocol is employed that attempts to find and forward frames over alternate paths that are shorter than their corresponding tree paths on the standard spanning tree, and makes use of the standard spanning tree for default forwarding. The proposed protocol, referred to as the Spanning Tree Alternate Routing (STAR) Bridge Protocol, is backward compatible with the IEEE 802.1D standard and has a complexity that is comparable to that of the standard and other existing protocols.

Abstract: An interconnect structure and method of communicating messages on the interconnect structure assists high priority messages to travel through the interconnect structure at a faster rate than normal or low priority messages. An interconnect structure includes a plurality of nodes with a plurality of interconnect lines selectively coupling the nodes in a hierarchical multiple-level structure. Data moves from an uppermost source level to a lowermost destination level. Nodes in the structure are arranged in columns and levels. Data wormholes through the structure and, in a given time-step, data always moves from one column to an adjacent column and while remaining on the same level or moving down to a lower level. When data moves down a level, an additional bit of the target output is fixed so data exiting from the bottom of the structure arrives at the proper target output port.

Abstract: The present invention provides a method called, the “cluster method”, for designing an efficient and low cost network that satisfies certain requirements, and in particular, that satisfies the requirement of having a prescribed number of nodes. The method first computes a provably optimal (or near optimal, in some cases) solution to small network design problems with the three following constraints. First, the network must be immune to the failure of a single link. Second, the network diameter cannot exceed a prescribed value. Third, the maximum node degree cannot exceed a prescribed value. The solutions to the small problems are combined, using an optimization technique called “dynamic programming,” to design large networks subject to the three above constraints. This cluster method is a hierarchical method, since the solutions to small problems are combined to solve a large problem. The resulting large network design meets the given survivability, diameter and maximum node degree constraints.

Abstract: System and methods for confining multicast routing trees to within single zones of a multi-zone communication systems, thereby enabling faster convergence of the trees relative to trees spanning multiple zones. Separate multicast routing trees are established using different multicast addresses in a source zone and one or more listening zones. Packets for a call distributed by routers (104, 116) of a packet network within the source zone via a source zone multicast address are received by a source zone packet duplicator (132). The source zone packet duplicator forwards the packets, via routers (116, 118, 120, 122) of the packet network using unicast routing, to various listening zone packet duplicators (136, 138). The listening zone packet duplicators, upon receiving the packets, separately distribute the packets within their respective zones via the packet network using different multicast addresses of the listening zones.

Abstract: A conferencing method not requiring additional or dedicated hardware in a processor controlled telephone terminal, nor requiring an external conference bridge, is provided by one of the terminals designating the conference, processing signals from two other conferees and delaying only two of the conferees active talkers at any given time. The two active conferees do not receive their own signal. An active conferee remains declared active during a dynamic hangover time, which varies between a minimum and a maximum corresponding to the activity time of the conferee.

Abstract: A system and method for isolating data messages received from subscribers in a CATV system are disclosed. The system includes a spectrum parallel router which receives data messages in the return spectrum of a service line at a service site. A switch at the service site directs data messages to service lines coupled to the site which have destination addresses corresponding to one of the service lines. Data messages not having a destination address corresponding to one of the service lines are provided to a transmitter for transmission to the next higher level of the CATV network over a return cable. Each service site has its own return cable which may be coupled to a distribution hub or a headend.

Abstract: A process for discovering a path from a source node to a destination node through a network by using “collisions” of randomly-propagating “feeler” packets originating from both the source node and the destination node. A discovered path is reported to the source node by the collision-detecting node where it may be stored and updated responsively to reports of new feeler packet collisions. Paths discovered and reported may be analyzed at either the collision-detecting node or the originating node to remove loops. The random collision-detecting path-discovery procedure reduces the operational traffic overhead associated with other exponentially-proliferating discovery methods. The feeler packets are propagated randomly through the network topology, thereby imposing relatively uniform path-discovery traffic effects in the network. Path discoveries arising from feeler-packet collisions always reflect current network topology and traffic conditions.

Abstract: An L bit for notifying another router of whether a self-router belongs to a connection-oriented network is newly provided in the options field of a conventional OSPF packet and the OSPF packet, including L bit is transmitted to another router. In this way, each router belonging a network can automatically recognize a router belonging to a connection-oriented network by detecting L bit. Then, by generating a routing tree, a connection-oriented network device can be identified in the routing tree and mapping between a connection-oriented network and a connectionless network can be performed in an edge device.

Abstract: The invention relates to a communications network for exchanging data packets of ATM connections in which, in network nodes of a lower network level, a data bank is provided in which connection data are kept available, wherein each data bank in a network node of a lower network level (L1) keeps available connection data for a closer environment (PGA1, . . . , PGA4, . . . , PGC), that at least one additional data bank (RSA1, . . . , RSC), which keeps available connection data for a wider environment, is provided and assigned to a network node, and that network node of a higher network level (e.g. A.1) which is responsible for a network node (A.1.