Concurrent Multipath Transfer using SCTP Multihoming: Transmission Policies using Potentially-failed Destination State

Previously, we identified the failure-induced receive buffer (rbuf) blocking problem in Concurrent Multipath Transfer using SCTP multihoming (CMT), and proposed CMT with a Potentially-failed destination state (CMT-PF) to alleviate rbuf blocking. In this paper we complete our evaluation of CMT vs. CMT-PF. Using NS-2 simulations we first show that CMT-PF performs on par or better than CMT during more aggressive failure detection thresholds than recommended by RFC4960. Next, we examine whether the modified sender behavior in CMT-PF degrades performance during non-failure scenarios. Our evaluations consider the following two end-to-end parameters: (i) realistic loss model with symmetric and asymmetric path loss, (ii) varying path RTTs. We find that CMT-PF performs as well as CMT during non-failure scenarios, and interestingly, outperforms CMT when the paths experience asymmetric rbuf blocking conditions. In light of our findings, we recommend that CMT be replaced by CMT-PF in existing and future CMT implementations and RFCs.