SF-SCTP: An Extension of Stream Control Transmission Protocol to Support QoS

Multiple streams in an SCTP association provide an aggregation mechanism to accommodate heterogeneous objects, which belong to the same application but may require different types of QoS from the network. However, the current SCTP specification lacks an internal mechanism to support the preferential treatment among its streams. Our work introduced the concept of grouping SCTP streams into subflows based on their required QoS. We proposed to modify the current SCTP to implement subflows, each with its own flow and congestion mechanism to prevent the so-called false sharing. In this paper, we integrate Fractional Congestion Control into subflow-capable SCTP (SF-SCTP) to improve the fairness of SF-SCTP towards the original SCTP. The throughput performance evaluation of SF-SCTP is studied through ns-2 experiments in a simplified Diff-Serv network. The results show that the proposed SF-SCTP design is able to support QoS among the SCTP streams and that false sharing is avoided. The results also indicate that SF-SCTP is more fair to the original SCTP after fractional congestion control is integrated into the design.