Research On Signaling Based Survivability In Intelligent Optical Network

The introduction of the generalized multi-protocol label switching (GMPLS) along with the RSVP-TE makes it possible to realize a series of intelligent functions such as rapid service provisioning and fast recovery, whose characteristics can be summarized as service-oriented. However, due to the problems in current restoration mechanisms, such as fast restoration and active restoration, the implementation of signaling schemes still faces some technical challenges, in terms of survivability, scalability. The research presented in this dissertation focuses mainly on three topics as follows:the impact of signaling mechanism to the restoration performance, the local node based fast restoration schemes, and the active fault alarm based restoration mechanisms. The mechanisms and algorithms presented in this dissertation have been emulated in the distributed intelligent optical network simulation platform. The simulation platform is aimed to do research of signaling based restoration technologies.The main innovations in this dissertation can be summarized as follows:(1) An OSNR-aware restoration lightpath provision mechanism (OSNR-LPM) for intelligent optical networks is proposed to reduce the blocking probability of distribuned wavelength assignment to solve the problem of false-success in restoration signaling which fails to take data plane performance parameters into consideration.(2) A local node based fast loop-back restoration mechanism and a sub-domain based fast loop-back restoration mechanism for RSVP-TE protocol of GMPLS is proposed to solve the problem that the traditional restoration has to be solved at the source node. Moreover, a fast restoration mechanism for multicast is also presented. It can effectively reduce the route length and the connection setup time of restoration operation. The simulation results and theoretical analysis show that under the restriction of recovey path length, these new schemes have less connection setup time than the traditional one.(3) Currently recovery approaches fail to deel actively with faults in intelligent optical network. Active-fault-alarm based pre-restoration scheme and active segment restoration are proposed. The simulation results show that these schemes based on active-fault-alarm technologies is able to achieve lower blocking probability and load burden to control plane in intelligent optical network.