A TCP toolkit for network simulation and emulation

The Internet has become an increasingly important part of our lives in recent years. As a result, a great deal of research is being done to improve its performance. However, studying the behavior of large and complex networks such as the Internet is a difficult task. It is crucial to have inexpensive and easy to use tools, such as network simulators and emulators, that can be used to perform repeatable experiments. These tools need to be able to model large and complex network environments in order to study realistic scenarios.; The Transmission Control Protocol (TCP) provides reliable end-to-end data communication between Internet applications. Since it is used by a large number of Internet applications, the performance of TCP implementations can improve the overall efficiency of the Internet. Since there are several TCP variants deployed on computer hosts, tools for assessing TCP performance need to implement a collection of algorithms to model them.; For this thesis, a TCP toolkit which models three of the most widely deployed TCP variants was developed. This toolkit is implemented in a parallel network simulation and emulation environment that can model large-scale networks. Experiments were conducted in both the simulation and emulation environments to verify that the toolkit works correctly. The toolkit can potentially be used to study network protocols and applications over Internet-scale networks.