End-to-end self-healing SDH/ATM networks

Abstract

In considering end-to-end self-heding capabilities, various network evolution scenarios have to be looked at. Network evolution scenarios, such as an embedded SDH/SONET network migration to a hybrid STM/ATM network or deployment of a new all-ATM access, have different architecture characteristics, and thus may lead to different self-healing solutions for providing network survivability. This paper reviews the self-healing schemes for the end-to-end network architecture evolution, introduces some new schemes for ATM networks and segment based self-healing strategies to provide flexibility of deploying various survivable network architecture scenarios, and provides a perspective on guiding current and future self-healing network architecture planning.

ATM scenarios for SDH/SONET networks

“…In the event of a failure affecting the ATM traffic, the separate ATM modules within the NEs (hybrid SNCP, hybrid MSSPRING) or outside them perform VP reroute/protection switching. 7 ATM VP protection switching could restore the ATM-specific defects, such as loss of cell delineation and cell routing map corruption. However, a largescale defect, such as a facility or node failure, will cause a defect on each virtual channel, leading to hundreds or thousands of separate detection/processing/ protection operations.…”

An overview of broad-band access technologies

“…The TMN tools facilitate a flexible and preventive network reconfiguration, when necessary, with the help of a set of statistics given by the three management levels mentioned just above [37]. This is why many carriers consider an adaptation of SDH to the feeder network, which interconnects the public switched network and the access network itself.…”