Improving Throughput in SCTP via Dynamic Optimization of Retransmission Bounds

Abstract

The Stream Control Transmission Proto-col (SCTP) is a relatively new transport protocol. Ithas several underlying mechanisms that are similar tothe Transmission Control Protocol (TCP), as well asseveral improvements that are important in certainclasses of applications. The timeout scheme of SCTP,however, is almost identical to that used in TCP.With the dynamics of today’s Internet, that timeoutscheme may be too passive. This paper presents an al-gorithm which dynamically adjusts the overall contextof the retransmission timeout process without chang-ing the fundamental retransmission mechanisms. Thisapproach manages the impact of fast retransmissionsand timeouts to significantly improve the throughputof SCTP applications. The algorithm has been im-plemented and tested in real network environments.Experimental results show that the algorithm avoidsspurious retransmissions and provides better through-put by intelligently managing RTO boundaries andallowing conventional timeout schemes to participatemore actively in the retransmission process.

Intelligent Transport Layer for Bandwidth as a Service in Cloud and IoT Applications

“…Examining the "Covetous Band-width Effect" in order to further refine the bandwidth control algorithm, modifications of transport level reliability param-eters for more efficient utilization of bandwidth, leveraging SCTP multi-homing within the cloud environment for more efficient path selection, and investigations into packet processing offload techniques are additional areas of further research [11,29]. Currently we are investigating extension of the work in to BAAS and also looking into green computing issue in BAAS [24].…”

“…This implies that the AIMD increase in the congestion windows by the SCTP stack after an RTX may be too aggressive, causing more RTXs to occur unnecessarily. One solution to this issue is to modify the transport layer to have direct knowledge of the bandwidth limitation, allowing us to consider previous work which modifies transport level parameters (RTO, etc) to improve throughput in similar situations [12,24].…”