Modelling and control of IP transport in cellular radio links
| Authors: | Möller Niels, Royal Institute of Technology, Sweden
Fischione Carlo, University of L'Aquila, Italy
Johansson Karl Henrik, Royal Institute of Technology, Sweden
Santucci Fortunato, University of L'Aquila, Italy
Graziosi F., University of L'Aquila, Italy |
|---|
| Topic: | 3.3 Computers and Telematics |
|---|
| Session: | Control Methods for Communication Networks |
|---|
| Keywords: | TCP, WCDMA, Power control, Feedback control, ARQ |
|---|
Abstract
A fundamental assumption of the TCP protocol is that packet lossesindicate congestion on the network. This is a problem when using TCPover wireless links, because a noisy radio transmission mayerroneously indicate congestion and thereby reduce the TCP sendingrate. Two partial solutions, which improve the quality of the radiolink, are power control and link-layer retransmissions. We consider aradio channel with multiple users and traffic classes, and investigatehow parameters in the radio model influences TCP-related qualitymeasures, such as the average delay and the probability of spurioustimeout. The results indicate that theouter loop power control is robust to uncertainties in the radiomodel. This robustness property supports separation between the radiolayer design and the IP and TCP layers.
