Development Framework for Supporting Java NS2 Routing Protocols

This paper presents a framework for developing and executing Java routing protocol implementations within the network simulator NS2. NS2 provides extensive support for developing C++ routing protocols, but has no Java support. In this paper, we describe extensions we have made to the AgentJ toolkit that enable routing protocols to be integrated directly into NS2 without needing to extend the internals of NS2 for each new protocol. The framework defines a reusable AgentJ routing protocol definition that can be used to register new protocols dynamically from within Java code. The actual routing protocol can then leverage the AgentJ toolkit for executing unmodified Java applications in NS2. By means of aspect-oriented byte-code rewriting, AgentJ allows preexisting Java routing protocols, which run on the Internet, to run unmodified within NS2. This powerful system also helps researchers to both understand high-level and algorithmic properties of a given Java routing protocol through the analysis of an NS2 simulation and to rapidly develop and debug new routing protocols through prototyping and experimentation.