Synchronous networking-SONET and the SDH

Describes how the new synchronous transmission standards may be used to provide a managed transmission infrastructure to provide flexible allocation of transport capacity to various service networks. The general principles of the network architecture are illustrated. This illustrates a small section of a network comprising three service nodes each having a digital cross-connect system (DCS). As examples of service layer network components, two switches, an RCU, a 64 kbit/s cross connect and a flexible access system are shown. The DCSs are used under the control of the network management function to allocate circuit paths between service layer entities to form service networks