Transmission Scheduling Optimizations for Concurrent Multipath Transfer

SCTP is a general-purpose Transport Layer protocol with out-of-the-box support for multi-streaming as well as multihoming. A protocol extension, which is denoted as CMTSCTP, extends SCTP by supporting Concurrent Multipath Transfer (CMT). That is, multiple network paths are utilized simultaneously in order to improve the payload data throughput. However, dissimilar paths – i.e. paths having different delays or bandwidths – are challenging and also very likely in internet setups. In this paper, we show how CMT-SCTP data transport performance can be improved by combining multi-streaming with an advanced stream scheduling policy and SCTP API enhancements. The performance benefit of our approach in dissimilar path setups is proven by simulations.