Abstract: A communication system includes multiple network interfaces interconnected using synchronous transport resources, such as a SONET ring. These interfaces couple to various communications networks and provide access for these networks to the synchronous transport resources. In response to relatively simple commands, these interfaces may couple attached asynchronous networks to the synchronous transport resources. With appropriate messages communicated to two of these interfaces, this system provides for the provisioning of synchronous transport resources between two asynchronous networks to support network-to-network communications.

Abstract: An Asynchronous Transfer Mode switch and method which facilitate priority arbitration of point-to-point and point-to-multipoint transmission are disclosed. To execute point-to-multipoint operation a bandwidth arbiter maintains a first list of connections and bit vectors indicating designated destination ports. The list maintained by the bandwidth arbiter is then compared to an unassigned output port bit vector to determine matches therebetween at which point-to-multipoint transmission may be made by utilizing instantaneously unused bandwidth within the switch. To execute point-to-point operation each input port maintains a list of connections associated with each output port, and those lists are used in conjunction with output port request information per input port in the bandwidth arbiter to match requests to the unassigned output port bit vector. The bandwidth arbiter may also assign priority to connections in the list.

Abstract: A water resistant enclosure providing protection to electrical or electronic equipment contained therein includes a three-sided removable cover pivotally coupled to a wall mounting bracket that includes a back panel-base plate combination. The three-sided removable cover further includes an enclosure door that covers the front opening. The three-sided removable cover also includes features to provide for water resistance. These features include an overhang extension from the top side wall of the three-sided removable cover extending to partially cover the front opening and in particular to cover the seam created between the enclosure door and the removable cover, and a gutter surrounding the front opening to divert water therefrom. In addition, the three-sided removable cover and the wall mounting bracket include elements to provide for the proper alignment and orientation thereof when being mated together.

Abstract: In a usage parameter control device for an asynchronous transfer mode communications system, a determination is made as to whether either of the respective storage elements maintaining values for (1) the time of arrival of a cell (TTA and (2) the time value at which the “bucket” will have drained to an empty condition (TTAT) has wrapped relative to the other. The wrap determination is made prior to the comparison between the TTA and TTAT values which is made in order to determine whether the user is complying with his or her contracted parameters. If one of the storage elements has wrapped relative to the other, the comparison between the TTA and TTAT values is modified accordingly.

Abstract: A method of facilitating traffic engineering services by communicating application objects over soft state process messages includes receiving an external soft state process initiating message at an ingress node to a core cloud, the core cloud comprising a plurality of nodes associated with a central processor, and generating an internal soft state process initiating message including an appended first application object. The method further includes communicating the internal soft state process initiating message to an egress node of the core cloud, receiving at the ingress node an internal soft state process confirming message including an appended second application object, and providing a traffic engineering service based, at least in part, on the first or second application data.

Abstract: An electronic chassis providing front access for printed circuit board insertion and removal and for cable connectors. The electronic chassis includes a backplane assembly and a shelf assembly. The backplane assembly includes a motherboard having a first plurality of connectors for receiving respective daughter cards and/or modules and a second plurality of connectors for receiving signal and/or power cables. Both the first and second pluralities of connectors are mounted on the same side of the motherboard. The shelf assembly includes a housing with opposing sidewalls, a top cover, a bottom support section, and a front cover. The backplane assembly is coupled to the shelf assembly such that the first plurality of connectors is disposed in the housing of the shelf assembly opposite the front cover, and the second plurality of connectors is external to the shelf housing.

Abstract: A method of transporting asynchronous transfer mode cells and time-division multiplexed information over a common fiber ring includes receiving a plurality of incoming signals comprising asynchronous transfer mode cells, legacy data, or time-division multiplexed information, formatting the plurality of incoming signals into a first plurality of incoming transport signals comprising asynchronous transfer mode cells and a second plurality of incoming transport signals comprising time-division multiplexed information, constructing from the first plurality of incoming transport signals a first outgoing synchronous transfer mode signal comprising at least one asynchronous transfer mode cell, constructing from the second plurality of incoming transport signals a second outgoing synchronous transfer mode signal comprising time-division multiplexed information, and transmitting the first and second outgoing synchronous transfer mode signals over a common fiber ring.

Abstract: A system for automatic program generation which receives a number of input format descriptors and a number of output format descriptors. The system generates a program for converting an input data sequence having a format described by input format descriptors to an output data sequence having a format described by the output format descriptors. The program may then be executed responsive to an input data stream, wherein a portion of the input data stream corresponds to the input data sequence. The input data sequence and output data sequence consist of a number of data type indicators. In an exemplary embodiment, the input data type indicators correspond to fields of data units received by a forwarding device, and the output data type indicators correspond to fields of corresponding data units forwarded by the forwarding device.

Abstract: A telecommunications switching apparatus (10) includes optical paths (16-19) coupled to interface cards (26-29), which in turn are coupled to a switching circuit (41-42). The switching circuit is coupled to a plurality of universal connectors (71-74), each of which is coupled to an auxiliary connector (77-78). The universal connectors can each removably receive any one of several types of switching circuit cards (101-104), which each utilize a respective one of several different communication protocols. An auxiliary circuit card (107-108) may be provided in the associated auxiliary connector, in order to support switching circuit cards that use certain communication protocols. The optically transmitted information includes segments formatted according to respective communication protocols, and is converted from optical to electrical form by the interface cards.

Abstract: A system and method for topology constrained routing policy provisioning between a plurality of sites in a Virtual Private Network (VPN) is disclosed. The method comprises enabling graphically defining of relationships between the plurality of sites of the VPN; and automatically generating at least one routing rule for each site of the VPN based at least in part on the defined relationship.

Abstract: A system and method for topology constrained Quality of Service (QoS) provisioning between a plurality of sites in a Virtual Private Network (VPN) is disclosed. The method comprises enabling graphical definition of relationships between the plurality of sites of the VPN and enabling graphical definition of at least one QoS rule for at least one pair of sites of the plurality of sites of the VPN based at least in part on the defined relationship.

Abstract: A system of route target filtering includes an import filter receiving a plurality of routes having a next hop routing information. The import filter accepts a first subset of the routes according to an import target policy. The system further includes a re-export filter also receiving the plurality of routes. The re-export filter modifies the next hop information of a second subset of the routes, and distributes the modified routes.

Abstract: Metal spring gaskets for EMI shielding in linecard plug-in units are improved by coverings of conductive fabric adhered to the springs with conductive adhesive.

Abstract: Each switch along a call setup path in a network decides whether the call request should be upgraded from a non-flow-controlled service type to a flow-controlled service type. Each switch bases the decision on whether a boolean variable for the calling subscriber that appears in a management information base (MIB) is set to a value indicating that the subscriber is entitled to the upgrade. In addition, the upgrade is performed only if an interface on the route to the called party on which the call setup request is to be forwarded supports flow-controlled connections. When the call is to be upgraded, the switch replaces the service type indicator in the setup message with a value indicating a flow-controlled service type, and forwards the setup message toward the called subscriber.

Abstract: An optical system includes a number of substantially identical, tunable, wavelength-preserving, optical regenerators 10. Each of the regenerators 10 is tuned to a different wavelength so that when a regenerator 10 is tuned to a given wavelength that regenerator will generate a regenerated, reshaped and retimed optical signal at the same given wavelength. The system also includes a multiplexer 32 coupled to receive and combine regenerated optical signal from each of regenerators. A filtering system (34) is provided, either internal or external to regenerators 10, to demultiplex different wavelength signals from an aggregate WDM optical signal.

Abstract: A method for allocating transmission bandwidth to a group of real-time variable bit rate connections includes determining an acceptable cell loss probability for a real-time variable bit rate group based on quality of service requirements for real-time variable bit rate connections in the real-time variable bit rate group. An allocation bandwidth is determined for the real-time variable bit rate group from a probability density function of an aggregate cell arrival rate for the real-time variable bit rate group. The allocation bandwidth is the bandwidth that the probability of the aggregate cell arrival rate exceeding the bandwidth is less than or at least substantially equal to the acceptable cell loss probability.

Abstract: In a usage parameter control device for an asynchronous transfer mode communications system, a determination is made as to whether either of the respective storage elements maintaining values for (1) the time of arrival of a cell (TTA) and (2) the time value at which the “bucket” will have drained to an empty condition (TTAT) has wrapped relative to the other. The wrap determination is made prior to the comparison between the TTA and TTAT values which is made in order to determine whether the user is complying with his or her contracted parameters. If one of the storage elements has wrapped relative to the other, the comparison between the TTA and TTAT values is modified accordingly.

Abstract: In a usage parameter control device for an asynchronous transfer mode communications system, a time counter is divided into multiple phases to enable audits of each of the virtual connections being handled by the system to be performed on a staggered group-by-group basis rather than all at once, thereby avoiding excessive delays in cell processing.

Abstract: A network device operates to control the clumping of cells on a connection using a rate-based flow-control protocol. In each of successive intervals, a number N is calculated representing the maximum number of cells permitted to be transmitted consecutively. N is calculated as the quotient from dividing a cell delay variation tolerance (CDVT) by the difference between the reciprocal of an allowed cell rate (ACR) and the reciprocal of a link cell rate (LCR). If the calculated quotient is greater than a number NRM for the connection indicating the maximum number of data cells allowed between forward flow-control cells, then N is set equal to NRM. A value C is calculated as the largest integer factor of NRM that is no greater than N, and the interval is then divided into NRM/C sub-intervals. No more than C cells are allowed to be transmitted on the connection in each of the sub-intervals.

Abstract: A lightpipe system for transferring light from light sources on a printed circuit board (PCB), such as light-emitting diodes (LEDs), to a display includes modular lightpipes coupled together. Each modular lightpipe couples to an adjacent modular lightpipe to form an integrated lightpipe system. All or selected numbers of the lightpipes may include detachable tabs, proturbances, pegs, or other structures to ensure proper alignment of the lightpipe system and attachment of the lightpipe system to the PCB.