SACK TCP Resilience Improvement with OPNET
نویسندگان
چکیده
SACK TCP was designed to be capable of surviving multiple segment loss. This can occur during network congestion as well as network failure. We studied the resilience behavior of SACK TCP in both cases and found that there is a critical point at which the behavior of SACK TCP changes significantly. If the number of lost segments in one transmission window is greater than this critical number, SACK TCP cannot recover efficiently and resorts to timing out. In this paper we document a change to the OPNET version of SACK TCP that improves the protocol’s resilience significantly, both during network congestion and for network failure. This proposed change decreases the transmission time increase resulting from lost segments by at least 87%.
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