Optimized design and availability analysis of large-scale shared backup path protected networks

摘要

Traditional integer linear programming model for shared backup path networks allows only one working route and one backup route per demand and does not scale well. By introducing multiple working routes and backup routes, the traditional multi-flow model solves in a faster manner. This paper seeks improvements on the traditional multi-flow model and develops an algorithm to assess availability for multi-flow shared backup path protection models. Experiments on 165 networks testify that the newly proposed model is 51% faster on average with similar total cost and overall network availability, compared with the traditional multi-flow model. All the networks in this paper are designed to be 100% single-failure restorable, and major findings regarding these networks include: (1) total cost of assigning backup capacity to each span dwindles away with increasing network average nodal degree; (2) network availability first rises then falls as network average nodal degree increases; and (3) when network scale increases, network availability decreases with fluctuations. The results found are explained with two case studies in this paper.