Research Article
New cross-layer channel switching policy for TCP transmission on 3G UMTS downlink
@INPROCEEDINGS{10.1109/WTS.2008.4547562, author={ D. Kumar and D. Barman and E. Altman and J.-M. Kelif}, title={New cross-layer channel switching policy for TCP transmission on 3G UMTS downlink}, proceedings={Wireless Telecommunications Symposium}, publisher={IEEE}, proceedings_a={WTS}, year={2008}, month={6}, keywords={}, doi={10.1109/WTS.2008.4547562} }- D. Kumar
D. Barman
E. Altman
J.-M. Kelif
Year: 2008
New cross-layer channel switching policy for TCP transmission on 3G UMTS downlink
WTS
IEEE
DOI: 10.1109/WTS.2008.4547562
Abstract
In 3G UMTS, two main transport channels have been provided at the layer-2 (MAC) for downlink data transmission: a common FACH channel and a dedicated DCH channel. The performance of TCP in UMTS depends much on the channel switching policy used. In this paper, we first propose and analyze three new basic threshold-based channel switching policies for UMTS that we name as QS (Queue Size), FS (Flow Size) and QSFS (QS & FS combined) policy. These policies significantly improve over a 'modified threshold policy' in (B. J. Prabhu et al., 2003) by about 17% in response time metrics. We further propose and evaluate a new improved switching policy that we call FS-DCH (at-least flow-size threshold on DCH) policy. This policy is biased towards short TCP flows of few packets. It is thus a cross-layer policy that improves the performance of TCP by giving priority to the initial few packets of a flow on the fast DCH channel. Extensive simulation results show that FS-DCH policy improves over others by about 30% to 36% in response time metrics for a particular case.
