Date Added: Dec 2009
In this paper, the authors describe their modifications to ospfd, a popular open-source implementation of OSPF routing protocol. The ospfd software can also be run in simulation mode, where processes, representing individual routers, communicate with each other over UDP sockets. Even though ospfd provides a fine-granularity implementation of OSPF protocol, its simulation mode operation leaves a lot to be desired. The main weakness of ospfd's simulation mode operation is its lack of distinction between the real time and simulated time. The simulated time is represented in terms of ticks and increases at the same rate as the real time, i.e. the duration of an individual tick is fixed (e.g. 50ms).