Authors: Juan J. Alcaraz, Fernando Cerdan
Addresses: Department of Information Technologies and Communications, Technical University of Cartagena, Plaza del Hospital, 1, 30202, Spain. ' Department of Information Technologies and Communications, Technical University of Cartagena, Plaza del Hospital, 1, 30202, Spain
Abstract: TCP performance over 3G links can be enhanced by means of Active Queue Management (AQM) techniques at the downlink buffer of the mobile network link layer (RLC). In this paper we describe Slope Based Discard (SBD), a novel deterministic buffer management technique with a discarding policy based on the observation of the filling rate of the buffer. Compared with the classic Random Early Detection (RED) scheme, SBD has a simpler operation and is best suited to multiplex short- and long-lived flows simultaneously. By means of extensive simulation experiments we compare the performance of TCP over three different RLC buffer management schemes: drop-tail (no AQM), SBD and RED. The simulation scenarios are configured to evaluate how the end-to-end goodput and delay are influenced by the number of multiplexed flows, the TCP flavour, the buffer size and the wireless channel error rate.
Keywords: TCP performance; 3G links; active queue management; radio link control; cross-layer design; mobile networks; buffer management; 3G radio bearers; discarding policy; simulation; transmission control protocol.
International Journal of Wireless and Mobile Computing, 2009 Vol.3 No.3, pp.177 - 188
Available online: 11 Oct 2009 *Full-text access for editors Access for subscribers Purchase this article Comment on this article