Priority Flow Admission and Routing in SDN: Exact and Heuristic Approaches

TL;DR

This paper introduces a priority-aware admission and routing scheme for SDN, offering exact and heuristic solutions that efficiently handle large network instances with high solution quality.

Contribution

It presents the first combined exact and heuristic methods for priority-based flow routing in SDN, utilizing ILP and genetic algorithms.

Findings

Optimal solutions are found within seconds for large networks.

Heuristic solutions achieve about 95% of the optimal.

Proposed approaches are effective for large-scale SDN routing.

Abstract

This paper proposes a novel admission and routing scheme which takes into account arbitrarily assigned priorities for network flows. The presented approach leverages the centralized Software Defined Networking (SDN) capabilities in order to do so. Exact and heuristic approaches to the stated Priority Flow Admission and Routing (PFAR) problem are provided. The exact approach which provides an optimal solution is based on Integer Linear Programming (ILP). Given the potentially long running time required to find an exact and optimal solution, a heuristic approach is proposed; this approach is based on Genetic Algorithms (GAs). In order to effectively estimate the performance of the proposed approaches, a simulator that is capable of generating semi-random network topologies and flows has been developed. Experimental results for large problem instances (up 50 network nodes and thousands of network flows), show that: i) an optimal solution can be often found in few seconds (even milliseconds), and ii) the heuristic approach yields close-to-optimal solutions (approximately 95\% of the optimal) in a fixed amount of time; these experimental results demonstrate the pertinence of the proposed approaches.