Abstract: A system operable to communicate time-division multiplexed information and asynchronous transfer mode cells includes a primary rate switching fabric operable to receive a first plurality of transport signals and to switch the first plurality of transport signals at a first level, a sub-rate switching fabric operable to receive a second plurality of transport signals carrying time-division multiplexed information and to switch the second plurality of transport signals at second level that is a more granular level than the first level, and an asynchronous transfer mode switching fabric operable to receive a third plurality of transport signals carrying asynchronous transfer mode cells, and to switch asynchronous transfer mode cells among the third plurality of transport signals carrying asynchronous transfer mode cells.

Abstract: A system operable to communicate time-division multiplexed information and asynchronous transfer mode cells includes a primary rate switching fabric operable to receive a first plurality of transport signals and to switch the first plurality of transport signals at a first level, a sub-rate switching fabric operable to receive a second plurality of transport signals carrying time-division multiplexed information and to switch the second plurality of transport signals at second level that is a more granular level than the first level, and an asynchronous transfer mode switching fabric operable to receive a third plurality of transport signals carrying asynchronous transfer mode cells, and to switch asynchronous transfer mode cells among the third plurality of transport signals carrying asynchronous transfer mode cells.

Abstract: A system includes a communication device that includes a number of interface cards and a switching complex. Upon receiving a data signal, an input card modifies header bits of the data signal to identify an input port on which the data signal was received. The switching complex uses the modified header bits to communicate the data signal to an output card and associated output port. In a particular embodiment, the switching complex may also modify header bits to identify the input card.

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 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 method for protecting virtual channel connection (VCC) traffic in a telecommunications system includes receiving a virtual path connection (VPC) at a destination node. The virtual path connection (VPC) is received on each of a working transmission link and a protection transmission link. The virtual path connection (VPC) includes a plurality of virtual channel connections (VCCs) A protection switching status is received for the working and protection transmission links. The virtual channel connections (VCCs) are selected from the working and protection transmission links for processing by selecting the virtual path connection (VPC) from one of the working and protection links based on the protection switching status for at least one of the working and protection transmission links.

Abstract: A hybrid protection circuit (10) operatively couples a plurality of communication paths in ingress cables (12) to a plurality of communication paths in egress cables (13). A line selector (31) effects protection switching of communication paths in one cable relative to communication paths in another cable, producing an output which is supplied to each of two switching sections (36, 37). The switching sections respectively effect switching according to a synchronous transport mode (STM) protocol, and an asynchronous transport mode (ATM) protocol. A multiplexer (57) selectively combines signals from the two switching sections, and supplies the result to a bridge circuit (61), which performs protection switching of these signals relative to communication paths in the respective egress cables (13).

Abstract: Methods and apparatus are provided for handling asynchronous transfer mode (ATM) cells sent from first user equipment through a plurality of ATM nodes and destined for second equipment, when the second equipment does not support ATM operations and maintenance (OAM) functionality. In particular, an ATM node connected to the second equipment is configured as an OAM proxy connection end-point for the second equipment such that ATM data cells which are destined for the second equipment are sent in a usual fashion, but ATM OAM cells destined for the second equipment are terminated and acted upon by the ATM node and are not forwarded to the second equipment. The proxy connection end-point functionality is preferably obtained by providing a user-friendly management information database (MIB) which stores configuration information for the ATM node.

Abstract: A method for identifying and declaring a physical loopback condition upon running an OAM loopback test is provided. The method modifies ITU-T Recommendation I.610. According to the method, an OAM loopback test cell is generated with a correlation tag and a loopback indication value representing an outbound (forward) test cell, with the correlation tag being stored. Upon receiving back an OAM loopback test cell, the value of the loopback indication is determined, and the correlation tag of the incoming OAM loopback test cell is compared with the stored correlation tag. If the correlation tags match and the value of the loopback indication represents a forward test cell, a physical loopback condition is declared. On the other hand, if the correlation tags match and the value of the loopback indication represents a backward test cell, a successful OAM loopback condition is declared.