Spare capacity allocation and optimisation in a distributed GMPLS-based IP/WDM mesh network

Abstract

IP over wavelength-division multiplexing (WDM) networks have been identified as promising candidates to underpin future telecommunication networks and thus industrial and academic researchers have been actively investigating key issues that affect the integration of IP and optical layers. An area of prime concern is network survivability. The main challenges within this domain are: to provide survivability schemes under different failure scenarios and to reduce the amount of required spare capacity while providing the required quality of service (QoS). Due to its flexibility and simplicity, one candidate technique is pre-allocated restoration. In this paper, the performance of pre-allocated restoration mechanisms are investigated considering a distributed GMPLS-based IP/WDM mesh network under single and dual-link failure scenarios. Several issues are considered. Firstly, two proposed spare capacity allocation schemes are investigated; link partitioning and lightpath partitioning. Secondly, the paper evaluates a retrial scheme that supports the utilisation of spare capacity. Thirdly, proposed class prioritisation scheme applied to the differentiated survivability concept with pre-allocated restoration is investigated. Finally, two load-based spare capacity optimisation schemes are proposed and evaluated; local spare capacity optimisation (LSCO) and global spare capacity optimisation (GSCO).