Effect of Delays on TCP Performance
Andrei Gurtov
In Proceedings of IFIP Personal Wireless Communications '2001, August 2001, Lappeenranta, Finland
[Full Text in PDF Format, 252KB]
Abstract
This paper has several contributions. First, we report that long sudden
delays
during data transfers are not uncommon in the GPRS wireless WAN. Long
sudden delays can lead to spurious TCP timeouts and unnecessary
retransmissions. Second, we show that the New Reno algorithm increases the
penalty of spurious TCP timeouts and that an aggressive TCP retransmission
timer may trigger a chain of spurious retransmissions. Third, we test how
four
widely deployed TCP implementations recover from a spurious timeout and
notice that two of them have severe problems to recover. Finally, we
discuss
several existing ways to alleviate the problems.