Generalized load sharing for packet-switching networks. II. Flow-based algorithms

For pt.1 see ibid., p.694-702 (2006). In this paper, we extend the load sharing framework to study how to effectively perform flow-based traffic splitting in multipath communication networks. The generalized load sharing (GLS) model is employed to conceptualize how traffic is split ideally on a set of active paths. A simple flow-based weighted fair routing (WFR) algorithm, called call-by-call WFR (CWFR), has been developed to imitate GLS so that all packets belonging to a single flow are sent on the same path. We have investigated how to couple the proposed basic packet-by-packet WFR (PWFR) and CWFR algorithms so as to permit a traffic splitter to handle both connection-oriented and connectionless traffic simultaneously. Our simulation studies, based on a collection of Internet backbone traces, reveal that WFR outperforms two other traffic splitting algorithms, namely, generalized round robin routing (GRR), and probabilistic routing (PRR). These promising results form a basis for designing future adaptive constraint-based multipath routing protocols.