Evaluation of RFC 4138

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Last updated 2007-11-19
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Forward-RTO recovery (F-RTO) specified in RFC 4138 is an algorithm for detecting a spurious retransmission timeout with TCP and SCTP. This document describes the advantages of F-RTO and summarizes the experience in its implementations and the experiments conducted with it. By analyzing the implications of the spurious retransmission timeouts on the regular RTO recovery and Forward-RTO recovery algorithm, including a detailed corner case analysis, it shows that F-RTO does not have negative impact on the network when used with an appropriate response algorithm even in the rare cases where F-RTO falsely declares a retransmission timeout spurious. It concludes with a recommendation that F-RTO is to be advanced to the standards track.


Markku Kojo (kojo@cs.helsinki.fi)
Kazunori Yamamoto (yamamotokaz@nttdocomo.co.jp)
Max Hata (hatama@s1.nttdocomo.co.jp)
Pasi Sarolahti (pasi.sarolahti@nokia.com)

(Note: The e-mail addresses provided for the authors of this Internet-Draft may no longer be valid.)