ISSN : 1796-2021
Volume : 1    Issue : 2    Date : May 2006

Round-trip Time Variation in SmoothTCP in the Face of Spurious Errors
Elvis Vieira and Michael Bauer
Page(s): 48-56
Full Text:
PDF (1,445 KB)

In this paper, we review the definition of a variant of TCP, called SmoothTCP, and describe one of its
versions which uses ICMP-SQ messages as its primary control metric. This version of SmoothTCP
is intended to be used in environments subject to spurious errors, such as in wireless networks.
We evaluate the behavior of this version of SmoothTCP by comparing it with the behavior of
Standard TCP in simulated environments with and without spurious errors. When there are no
spurious errors, Standard TCP inherently drops packets and suffers large variations in the
congestion window size causing large variations in round-trip time. In the case of spurious errors,
Standard TCP encounters wide round-trip time variations around the retransmitted packet that was
lost due to a spurious error. In both cases, SmoothTCP exhibits better performance with respect to
round-trip time variation.

Index Terms
congestion control, RTT, spurious errors, TCP performance, SmoothTCP, wireless performance.