Using Concurrent Multipath Transfer to Improve the SCTP Startup Behavior for PSTN Signaling Traffic

Although latency in the Internet has gained much attention in the research community, the latency issues of mobile control signaling have received less attention, and this all the while many telecom operators are experiencing a several-hundred percent increase in signaling traffic over only a couple of years. We believe one way to address both the latency and increased signaling load of mobile networks, is to exploit concurrent transfer of signaling traffic over several paths a.k.a. Concurrent multipath transfer. This paper studies whether or not SCTP extended with concurrent multipath transfer (CMT-SCTP) could provide a faster startup behavior than standard SCTP. The paper complements previous work on CMT-SCTP, and extends it to PSTN signaling traffic. The paper suggests that CMT-SCTP could give a faster startup behavior over paths with similar bandwidths and round-trip times, but that its behavior is sensitive to differences in round-trip time between the paths. Moreover, the paper suggests that provided CMT-SCTP is configured with large enough send and receive buffers, it could provide a faster startup behavior than standard SCTP over a multipath association, in spite of some of the paths having a packet-loss rate of several percent.