Abstract:
An apparatus that provides access (Fig. 5) between an enterprise network and at least one of a metropolitan area network and a wide area network. The apparatus includes an enterprise area network connection, a controller coupled to the enterprise area network connection, the controller providing Layer 1 and Layer 2 service (Fig. 4), and a central office connection coupled to a central office, the central office providing Layer 3 and Layer 4 service (Fig. 4).
Abstract:
The invention relates to a method for producing a computer-assisted real-time system that comprises at least one processing unit. Data exchange between said processing unit and the environment or one or more additional processing units is synchronous or asynchronous. At least one real clock is allocated to the processing unit to correlate data exchange, said clock being defined by the following relation (a).
Abstract:
Described is a method for managing flow of protocol information in a node of a hierarchical network in which the protocol information is communicated between network nodes in topology state elements. The method comprises checking topology state elements generated by the node to identify protocol information encapsulated therein, and selectively allowing transmittal of the topology state elements from the node to lower levels of the network based on the protocol information identified.
Abstract:
Various binding information techniques are provided for a telecommunications network (20) having separated call and connection layers. In a first embodiment of the invention, binding information is associated with connection endpoint information for a first connection end point (36A) at a first end node (22A) of the network. In a second embodiment, an ATM end system address (AESA) is associated with a first connection end point at the first end node and is transmitted in the call layer to the second end node, and included in connection layer signaling sent from the call layer to the connection layer. Upon receipt of the connection layer signaling at the first end node, the first end node uses the AESA to through connect the ATM switch in the physical layer to the first connection endpoint. In a third embodiment, a dynamic ATM end system address (AESA) is associated both with a first end node of the network and with a first connection end point at the first end node. Since the dynamic AESA is reusable for association with other connection end points at the first end node, a table maintained at the first end node keeps track for which end point the dynamic AESA is currently used. In a fourth embodiment, connection endpoint information for a first connection end point of a first end node of the network is included in a vacant or otherwise unused field in an ATM end system address (AESA) of the first end node.
Abstract:
A method of optimizing access network utilization is provided. The access network includes a plurality of integrated access devices (42) coupled to a segment and reassembly device (40), where each segment and reassembly device has a plurality of channels, X. The method includes the steps of providing a plurality of subscriber lines, (m i ) coupled to the integrated access devices, providing a plurality of integrated access device lines, (n i ) between the integrated access devices and the segment and reassembly device, multiplexing the plurality of subscriber lines by the integrated access device onto the plurality of integrated access device lines, such that Σmi,= Σni = X, and providing a reorder tone to any subscriber whose call is blocked.
Abstract:
A signal router routes N inputs to M outputs. All inputs signals are ultimately applied to a data buss by spreading across multiple buss lines and time multiplexing. The data are read from the buss and written in identical images to K random access memories. The memories are addressed and read according to a different schedule for each of K output signals that are ultimately demultiplexed to M outputs. As each RAM image is read, another RAM image is written and vice versa. Since each RAM image contains the same data, the generation of signals from each RAM to supply each of the respective K output signals can be done at a rate that is substantially more independent of the input, buss, or RAM write operations than prior art techniques permit.
Abstract:
A method is given for deriving a backup path routing spare capacity template that is feasible, scalable, adaptive, much faster, and near global optimal in redundancy reduction. The method includes determining working paths, aggregating the working paths into a first matrix, determining backup paths, aggregating the backup paths into a second matrix, and deriving the template from the first and second matrices. A method is also given for successively approximating the optimal spare capacity allocation needed for a network. The method includes, determining the link cost associated with a selected traffic flow's backup path, determining an updated link cost that is less than the current link cost, determining a backup path with the updated link cost, and notifying the rest of the network of the backup path.
Abstract:
A technique is described for providing service to multiple ports sharing common scheduling resources. According to one implementation, the scheduling technique of the present invention may be used to dynamically balance the frequency of needs of different client flows to the resource availability of the scheduling process for client flows which have relative time sensitive needs of service. Moreover, according to a specific implementations, the scheduling technique of the present invention may be used to provide efficient allocation of switching and/or scheduling resources across multiple ports even in the presence of dynamic port bandwidth changes.
Abstract:
A system and method for simulating a networked system for testing of embedded software on an emulated hardware device. The system provides for automated generation of a simulated hardware and facilitates testing of embedded software response to simulated error conditions created by the simulated hardware. Communications from the embedded software are intercepted at a low software level and redirected from the emulated hardware device to the simulated hardware.
Abstract:
The present invention relates to an interface device an, in particular an interface device for providing communication security services. The problem of providing communication security services to, for example, a pair of host computers that must communicate over an insecure public network is a widely addressed one. It is known to provide cryptographic functionality to a host computer such that data traffic transmitted by the host computer can be secured. However a major weakness of known methods is that such cryptographic processing is either carried out on the host or such that, following passing the data to be secured to an additional cryptographic accelerator device plugged into the host, the cryptographically processed data is passed back to the host before subsequent transmission. Both such methods give rise to a situation where, in the event of the host operating system being subverted, the original data and the cryptographically processed data are able to be simultaneously gathered on the host, giving rise to the classic "known plaintext" attack on the cryptographic key used in the encryption operation. According to the present invention however, an interface device is provided comprising a first interface for receiving data from a first zone in a first zone data format; means for processing said received data through performance of a cryptographic operation on at least a portion thereof; a second interface for sending said processed data to a second zone in a second zone data format; and means arranged to pass said processed data exclusively from said processing means to said second interface. In this way, in enforcing a unidirectional flow of information through the device and isolating all the necessary functionality (including, for example, the cryptographic key) on the device, the problems of the prior art are advantageously avoided.