Document Type


Date of Award

Spring 5-31-2003

Degree Name

Master of Science in Computer Engineering - (M.S.)


Electrical and Computer Engineering

First Advisor

Nirwan Ansari

Second Advisor

Dionissios Karvelas

Third Advisor

Sirin Tekinay


This thesis discusses the techniques to improve the TCP over wireless. The loss-intensive wireless communication results in high retransmission rates to recover lost packets and bandwidth consumption. In addition, the retransmitted segments have significant chance of being dropped. To make the retransmission process more granular, large segments at the transport layer (540 bytes, by default) can be subdivided into smaller sub-segments. This document introduces a split TCP based solution and describes how to produce a series of smaller-sized segments that share the same transport layer header. A new header format is introduced to support the transmission of smaller segments and to conserve bandwidth during transmission. The NACK-based message exchange method is adopted with a special windowing protocol to achieve reliability, flow-control, and efficient buffer handling. The simulation results indicate that use of sub-segments improves latency, throughput, bandwidth, power and other measurements. In addition to that, an analytical model is developed to study the influence of sub-segmentation over latency and throughput.