An evaluation of data link protocol performance over an ATM satellite link

Asynchronous Transfer Mode (ATM) is a transfer protocol that allows a single physical communications channel to carry multiple data streams. It is capable of carrying different types of digital traffic including voice, video, and other digital protocols. However, it also has a relatively high overhead-to-data ratio when compared to other protocols and it provides no native form of error correction or detection for data carried in its payload. These features of ATM suggest that it is probably better suited for use over channels that are high speed with low Bit Error Ratios but such communication channels tend to be rare or expensive. This thesis evaluates the performance of two different variants of the High-level Data Link Control (HDLC) protocol as they are sent over a relatively low-speed, error-prone ATM satellite channel. This was done by modifying the Point-to-Point Link Simulation Tool developed by Abdulaziz Hamad Al-Zoman, Ph.D. to model the various communication protocols and the communications channel.