On congestion problems in digital cross-connect (DCS) transport networks

In today's environment where traffic demands within a network are increasing rapidly, planning and designing a network are assuming great importance. Rapidly rising traffic within the network is leading to network congestion, requiring solutions to cope with the increasing demand. We address the question of network planning and design, focusing in particular on alleviation of congestion at digital-cross connect systems (DCSs) located at the nodes of a broadband transport network. We describe a constrained routing mechanism as part of a new design strategy, employing unique dynamically changing routing constraints. Also critical in network design and planning is the knowledge of DCS capacity lost to tie-trunks, when the requirement for DCS at a given node exceeds unity, and the DCSs need to be tied together to facilitate proper cross-connects. Therefore, this paper also provides a tie-trunk analysis, leading to mathematical expressions, which can act as useful guides in the judicious planning of DCSs at the nodes of the given network.