Abstract

Reliability is a performance metric typically defined in a Service Level Agreement. In an IP-over-WDM network, a guaranteed level of reliability per IP link by means of dedicated protection mechanism with a variable number of lightpaths has been recently proposed. However, it is well known that dedicated protection requires more resources than shared protection. Thus, we propose a new method to determine which backup lightpaths can be shared without violating the reliability requirements. Results show that the method is effective in sharing resources of backup lightpaths whilst guaranteeing the reliability requirements: resource savings of up to 21% were observed in the cases studied. © 2011 IEEE.