Sequence-preserving adaptive load balancers

Load balancing in packet-switched networks is a task of ever-growing importance. Network traffic properties, such as the Zipf-like flow length distribution and bursty transmission patterns, and requirements on packet ordering or stable flow mapping, make it a particularly difficult and complex task, needing adaptive heuristic solutions. In this paper, we present two main contributions: Firstly, we evaluate and compare two recently proposed algorithmic heuristics that attempt to adaptively balance load among the destination units. The evaluation on real life traces confirms the previously conjectured impact of the Zipf-like flow length distribution and traffic burstiness. Furthermore, we identify the distinction between the goals of preserving either the sequence order of packets, or the flow- to-destination mapping, showing different strengths of each algorithm. Secondly, we demonstrate a novel hybrid scheme that combines best of the flow-based and burst-based load balancing techniques and excels in both of the key metrics of flow remapping and packet reordering.