Efficient flow-aware dynamic link load balancing

Link Load balancing and serves as a useful abstraction for achieving bandwidth aggregation by means of aggregating multiple physical links into a single logical link. It is a key component of traffic engineering, link aggregation, and equal cost multi-path routing. Dynamic link load balancing needs schemes that dynamically distribute traffic across multiple paths at a fine granularity without disrupting the packet flows. This distribution should be fair in terms traffic distribution and link usage to ensure effective utilization of the available link capacity. Existing solutions exhibit a tussle between their efficiency in distributing flows uniformly across the links and their ability to avoid packet reordering within a flow. This paper examines the inadequacies and limitations manifested in the existing solutions and introduce a new scalable dynamic load balancing scheme that guarantees with a very high and programmable probability that the heavily loaded link is never assigned a new flow. The proposed method also guarantees that the packets belonging to a flow are never distributed among the links, thus avoiding reordering and packet loss.