Conference Paper

TCP Smart Framing: A segmentation algorithm to improve TCP performance

DOI: 10.1007/3-540-36480-3_20 Conference: Quality of Service in Multiservice IP Networks, Second International Workshop, QoS-IP 2003, Milano, Italy, February 24-26, 2003, Proceedings
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In this paper we propose an enhancement to the TCP protocol, called TCP Smart Framing , or TCP-SF for short, that enables the Fast Retransmit/Recovery algorithm even when the congestion window is small. TCP-SF is particularly ef- fective for short-lived flows, as most of the current Interne t traffic is. Without modifying the TCP congestion control based on the additive-increase/multiplicative- decrease paradigm, TCP-SF adopts a novel segmentation algorithm: while Clas- sic TCP starts sending one segment, a TCP-SF source is allowed to send an initial window of 4 smaller segments, whose aggregate payload is equal to the connec- tion's . This key idea can be implemented on top of any TCP flavor, from Tahoe to SACK, and requires modifications to the server behav ior only. Analytical results, simulation results, as well as testbed implementation measure- ments show that TCP-SF sources manage to outperform Classic TCP in terms of completion time.

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