Design and Implementation of Switches in Network Simulator (ns2)

Switches are necessary components of routers. They have attracted many attentions with rising demand of high-speed communication. Simulation plays more and more important role in studying switches. ns is a popular network simulator, however no support for switch. In this paper, we present the details of design and implementation of switch in ns. The switch is designed as an extension to ns module library. Our goal is to implement the common structure and functionality of switch, such as input and output ports, crossbar-based switch fabric, and arbitrating algorithm with simplicity and extensibility. By deriving from a basic class which is supported in ns, and modifying the process procedure of packets, switch is implemented as a standard module in ns library. The details of the developed switch and representative performance analysis which illustrates how to use the switch and its validation are presented as well