Abstract: A method is described for path selection in communications networks with multiple QoS metrics. This method takes an additive metric (say, cost) as a path minimization target and a concave metric (say, bandwidth) as a minimum requirement for each link. A potential objective is to find a path between a source node and a destination node in a communications network such that the bandwidth of each link in the path exceeds a bandwidth requirement and the cost of the path is minimized. The method eliminates from consideration those links whose available bandwidth does not exceed a required bandwidth. The method then reassigns the cost of those links whose available bandwidth does not exceed a function of the required bandwidth. A path from the source node to the destination node is then selected, using only links still under consideration, corresponding to a path wherein cost is minimized.

Abstract: A node in a packet network such as an ATM network receives a plurality of traffic classes and outputs them to an output link. The invention relates to a technique of scheduling the traffic classes in a time linked fashion at the node based on the bandwidth allocated to each traffic class. Traffic scheduling based strictly on priority may not satisfy delay and loss guarantees of traffic classes when there are many classes with many different priority levels. The rate based scheduling in a time-linked fashion solves these problems by limiting the bandwidth to which each class is accessible. According to one embodiment, the invention uses timeslot values and a linked list of the traffic classes.

Abstract: In the Intelligent Networks environment, where multiple Service Providers and multi-Vendor equipment are involved in new service offering, the risk of overloading the network elements are real and managing the traffic is a challenge. Network traffic overloads could result from equipment failures, major equipment outages, or widespread loads above engineered levels. To solve the problem of network traffic overload, a direct link interconnect feature between the two SCPs that are deployed in load sharing mode in the network is provided. The communications link interconnects the two SCPs within the load sharing group, whereby the SCPs may exchange information on their congestion levels and controls as well as route queries to the SCP that is not overloaded.

Abstract: An improved add/drop multiplexer in which groups of working channel tributaries have associated groups of protection channel tributaries is provided. Traffic is added by receiving it from an external service, and transmitting it on a configured group of working channel tributaries unless a protection event has occurred requiring it to be transmitted on the associated group of protection channel tributaries. Traffic received from protection or working channel tributaries is either dropped at the multiplexer if addressed to it, or transmitted on tributaries of the same type, be it working or protection. If working channel tributaries for use in the transmission relate to a physical link which is down, then the traffic is transmitted on the associated group of protection channel tributaries. In this way, all the working channel tributaries can be shared among users, rather than having a dedicated working channel tributary for each user.

Abstract: An access control system for a network manager system provided with a plurality of building blocks (BBs), each specialized for executing a plurality of functions on a plurality of resources of the network, and with a graphical user interface (GUI). Each BB comprises a database for storing access control data pertinent to said component including all resources accessible to the BB, all functions executable by the BB and all users that have the right to use the BB, according to privileges allocated to each user. The BB also comprises an access control library for writing and reading the access control data to and from the database for execution of a network operation according to the respective privileges. The access control system further comprises an access control user interface connected to the access control library of each BB, for viewing and editing the access control data on the GUI.

Abstract: A server provides a channel for previewing multimedia and a plurality of full screen multimedia channels. A client displays plural preview screens representing available multimedia channels from the server. Selection of a particular one of the plural preview screens at the client signals the server of the desired channel. The server then initiates streaming of the desired channel to the client. The server tracks the address of the user, the name of the stream and when the clip was started. After the client is finished viewing the stream another TCP connection is made to the server to unsubscribe. The server can therefore keep track of who has viewed which streams, for how long and at what time of the day. This method of tracking could also be used to track preview viewing.

Abstract: Methods and apparatus for control of a multi-class digital network are described. The network supports a plurality of digital services using dynamically-configured service bands to support various transport modes and qualities of service. Flexible controls with two degrees of freedom are used at the node level to dynamically configure the transport bands. The first degree of freedom is realized using adaptive alternate routing to balance the traffic intensity across the network and, hence, increase the efficiency of the band. The second degree of freedom is achieved through adaptive network partitioning to provide elasticity to the band structure. This permits band capacity to be adaptively reconfigured as connections are added and dropped. The switching nodes use rate controllers to divide the capacity of each link among the connection classes according to rules which ensure consistent service attributes for each band across the network.

Abstract: A telecommunication system and method of signalling are disclosed which enable service providers to integrate broadband network capability into their existing narrow band networks while being substantially transparent to existing narrow band signalling infrastructures such as the Common Channel Signalling System Number 7 (CCS7), currently in use. Significant advantages are realized through such a network system. Service providers, for example incumbent local exchange carriers (ILECs) now have access to BB connectivity while retaining the use of their extensive CCS7 signalling networks and Advanced Intelligent Network (AIN) resources. Investment in the CCS7 signalling infrastructure is hence not lost and the proven robustness and reliability of these networks is retained. Service providers can continue to take advantage of Intelligent Network capabilities in providing a large variety of voice services, but also to make available some of the current service features for future BB services.

Abstract: A method and a network for a universal transfer mode (UTM) of transferring data packets at a regulated bit rate are disclosed. The method defines a protocol that uses an adaptive packet header to simplify packet routing and increase transfer speed. The protocol supports a plurality of data formats, such as PCM voice data, IP packets, ATM cells, frame relay and the like. The network preferably includes a plurality of modules that provide interfaces to various data sources. The modules are interconnected by an optic core with adequate inter-module links with preferably no more than two hops being required between any origination/destination pair of modules. The adaptive packet header is used for both signaling and payload transfer. The header is parsed using an algorithm to determine its function. Rate regulation is accomplished using each module control element and egress port controllers to regulate packet transfer.

Abstract: In Asynchronous Transfer Mode (ATM) communications networks, certain congestion control features, such as Partial Packet Discard (PPD) and Early Packet Discard (EPD), operate on ATM cells that have been segmented from ATM Adaptation Layer #5 (AAL5) frames (packets). AAL5 frames are automatically detected by observing transitions of an indicator in the ATM cell header unique to AAL5 traffic. Automatic detection of AAL5 traffic allows enablement of packet discard techniques such as PPD and EPD.

Abstract: A fully meshed telecommunications network based on an optical core transport network having a plurality of optical nodes is described. An electronic edge switch is connected to an optical node and dedicated channels are established between all the possible pairs of electronic edge switches through their associated optical nodes and the optical core transport network. Connection paths are set up using a channel or channels between a pair of electronic edge switches which perform major functions concerning connection routes, including rate regulation, path establishment, etc.

Abstract: Congestion at a network node can be aggravated by having too many TCP connections. A simple method of avoiding the bad effects of too many TCP connections is to limit the number of connections. Limiting the number of connections is achieved by an admission control which delays or even discards the connection set-up packets. TCP traffic flows are monitored to generate packet loss characteristics and when a certain condition is met, a connection request queue is disabled.

Abstract: A fault tolerant modular computing or communications system is disclosed. The system comprises a plurality of primary processing modules and at least one spare module. These modules are preferably interconnected with a data network to switch and process network traffic. A control processing module controls overall operation of primary and spare modules. Upon failure of a primary processing module the control module senses the failure and determines if it is a recoverable fault, by preferably resetting the failed module. If fault is not recoverable, as manifested by an unsuccessful reset in a first sparing interval, data at the failed module is switched to a spare module. If the fault is recoverable and the reset is successful, data is not switched. If a subsequent failure of that module occurs in a second stability interval, data is immediately switched to the spare module. The system is particularly well suited for distinguishing software faults from non-recoverable hardware faults.

Abstract: The present invention relates to a lossy switch for processing data units, for example IP data packets. The switch can be implemented as a contained network that includes a plurality of input ports, a plurality of output ports and a lossy switch fabric capable of establishing logical pathways to interconnect a certain input port with a certain output port. A characterizing element of the switch is its ability to control the discard of data packets at a transport point within the switch. This control mechanism prevents and reduces congestion which may occur within the switch fabric and at the level of the input and output ports. The system also supports priorities, routing HI priority request data packets over the switch fabric before LO priority request data packets, and discarding LO priority data packets first when controlling congestion.

Abstract: A method is described for one-to-all route selection in Communications Networks with multiple QoS metrics. This method takes a first metric (say, delay) as a constraint and a second metric (say, cost) as an optimization target. A potential objective is to find a path between a source node and each node in a communications network such that the delay of the path does not exceed a path delay constraint and the cost of the path is minimized. The method selects a first path which is a shortest path from a source node to each node in terms of the first metric using Dijkstra's algorithm. A reachability graph is then constructed based on the first metric path constraint. Within the reachability graph, another path is found, which is a shortest path from a source node to each node in terms of the second metric, using Dijkstra's algorithm. Any path to a particular node selected within the reachability graph replaces the first path to said particular node.

Abstract: The user interface is divided into client-server portions, based on the multilevel model-view-controller (MMVC) architecture. The MMVC architecture results in a high performance user interface that addresses the problem of how to divide functionality, and introduces performance issues in a distributed or three-tier architecture. This division of concerns results in a dramatic reduction in the size of the component which runs on the user's terminal, resulting in lighter weight client interfaces, that are flexible and powerful and does not require to have a high bandwidth connection to the server. Thus, the user's terminal may be a low-end personal computer with a dial-up access to the Internet service provider. This layered structure may be built over an existing network manager provided with a graphical user interface.