Dynamic routing of anycast and unicast traffic in Elastic Optical Networks

In this paper, we focus on issues related to dynamic routing of anycast and unicast traffic demands in Elastic Optical Networks (EONs). The growing interest in cloud computing and content-oriented services triggers the need to examine anycast traffic in the context of the EON concept, which is perceived as a promising approach for future optical transport networks. Anycasting - defined as one-to-one of many transmission - ideally corresponds to concepts of cloud computing and content-oriented services, where the same service/content is available in many, geographically spread data centers. In the paper, we propose two types of algorithms for dynamic routing of anycast and unicast requests. The former algorithm is based on the shortest path first (SPF) method, while the latter algorithm is based on the selection of a routing path from a set of candidate paths (CP). To examine performance of the algorithms, we run simulations using a real pan-European topology and traffic patterns created according to Cisco predictions. The results show a tradeoff between SPF and CP methods in terms of the blocking probability and execution time. Moreover, we observe that the blocking probability depends on the number of data centers placed in the network.