Interactions between TCP and link layer protocols on mobile satellite links

The performance of TCP degrades considerably on land-mobile satellite communication channels because of the long propagation delays and frequent correlated packet losses. In order to improve TCP performance on such channels, several techniques have been proposed including the use of link layer automatic repeat request (ARQ) protocols. This paper extends previous work by examining in greater detail the interactions between TCP and link layer ARQ protocols. We present a link layer selective repeat ARQ protocol that is specifically designed for particular mobile satellite communication systems. The performance of TCP with this link layer ARQ protocol is evaluated using a flexible test environment which is integrated with the Linux TCP/IP stack.