The Performance of HTTP over Satellite Random Access Channels

This paper attempts to measure the performance of the Hyper Text Transfer Protocol (HTTP) (Fielding et al. 1997) in a multiple access, satellite environment. The HTTP client’s access to the Internet is via a shared satellite uplink channel. The multiple access protocols we have chosen to simulate are Slotted ALOHA (Kleinrock and Lam 1975) and Reservation ALOHA (Crowther et al. 1973). We have constructed a detailed simulation of “web browsing” behavior using ns-2.0 (McCanne 1998) and have used this to simulate HTTP transfers over random access satellite channels. The purpose of this work is to determine if current medium access techniques are sufficient to accommodate many terrestrial users whose traffic patters are dominated by HTTP client-server behavior.