Digital cross-connect (DXC) systems are used at major network nodes to cross-connect a number of inbound and outbound circuits. The cross-connecting of circuits is done when circuits are provisioned, but, typically, cross-connects are also used to implement various schemes for protection switching and network restoration. In the SDH market, the abbreviation “DXC” is used for digital cross-connects, whereas they are referred to as “DCSs” in the SONET world.