Dynamic frequency slot allocation on IP-over-EON access links with multiple-type and time-varying traffic

Abstract

Access links that connect client networks to public networks have to carry multiple-type and time-varying traffic. Those hybrid traffic flows compete for limited bandwidth, yet at the same time have drastically different performance requirements. As planning the link capacity for peak traffic demand is not economically viable, it is important that bandwidth on the access links is shared between different traffic classes in a way that maximal network utility can be achieved. In this paper, we study the frequency slot allocation problem on IP-over-elastic optical network (EON) access links that carry three types of traffic, namely, packet streams, latency critical circuit connections (e.g., video conferencing), and delay tolerant circuit connections (e.g., bulk data transfers). We define four network operation states; in each of which an access link serves traffic with different levels of fulfillment. We then formulate the allocation problem into a weak-constrained optimization problem and propose a genetic algorithm to solve it in real time. Numerical results show that the relative error of the genetic algorithm is within 3% and the access link keeps maintaining the optimal achievable network operation state. We also show that, by increasing the storage size, the access link can adapt to the increasing traffic load within a certain range without upgrading the expensive access link bandwidth. Our study provides useful insights in managing and operating IP-over-EON access links, and the concept of multiple network operation states can be generalized to networks that serve more than one type of traffic.