Integrated Self-healing Network For STS-1/STS-3C Path Level Restoration

Recently, DCS(Digital Cross-Connect Systems) based self-healing network has been actively studied, which is applied to a mesh-type network and is based on distributed control of DCS’s. We have proposed our self-healing algorithms, called TRANS( formerly called NETRATS), where both line and path restoration can be performed. The self-healing network has such features as fast and flexible restoration, a capability to handle multiple and even node failures, and so on. In this paper, the initiation of the self-healing algorithm is discussed in a practical SONET environment, where a variety of NE’s such as DCS and ADM(Add-Drop Multiplexers) must be accommodated. The results indicate that the STS-l/3c path level restoration is preferable in such an environment, from a local algorithm initiation viewpoint. In this case, the algorithm is basically initiated in DCS’s upon detection of each STS-l/3c path AIS. Furthermore in this paper, a joint use of the ring architecture and the self-healing algorithm is proposed in order to recover from a various failure scenarios. In order to enable the integrated control, a sender and chooser information for each STS-l/3c path must be provisioned beforehand to a pair of DCS’s. Moreover, a ring initiation flag is assigned to ADM’s and DCS’s for each STS-l/3c path. Through the proposed integrated self-healing, the flexible and cost-effective network survivability can be realized. NOMS ’92 9.1.1 CH3134-419210000-0219 $3.00