 from the incoming data plane signals Regeneration or amplification if required Switching through the equipment switching fabric Multiplexing of the tributaries directed toward the same output line Addition to each multiple section of the service channel with the relevant information Naturally, it is possible that not all the aforementioned functions are really present. For example, if an OXC is connected to the client ports of a WDM system, it is the transport system that operates multiplexing and demultiplexing and the OXC has not to perform these functions again. Switching Systems: Architecture and Performances 7.7.2 Connection Management This class collects all the functions needed to run correctly the procedures and protocols needed to set up, manage, and tear down a connection. An example of connection management is given by the connection switching control. As a matter of fact, to prevent misrouting of entire physical layer connections, when network manager controls the physical layer, each connection is tagged with an ID num- ber, that is generally a field of the record containing the information about the connection. The cross-connection status is memorized into the database of the switch by a data table (at least at the logical level) relating each incoming connection ID with an input port num- ber and an output port number. The switch continuously monitors the ID of the connections entering the input ports and exiting the output ports to verify both that the arriving connections are correct (i.e., no switching errors occur in the previous switches) and that its own switch is transferring all the connections at the correct output port. This operation, if the network is managed by the ASON/GMPLS control plane, is per- formed not with IDs and ports numbers, but with generalized labels and ports IP addresses, exploiting the potential of the GMPLS protocols. However, a completely analogous control has to be done, to prevent errors. Another important connection management operation is related to the terminat