Next, we ran some large experiments with an actual ad hoc wireless network routing protocol, ZRP (Zone Routing Protocol). Figure 6 shows the time and memory required to simulate different size networks at a fixed density of 10 neighbors per node. The experiments were run on a dual-processor 2.8 GHz Intel Xeon machine with 2GB of RAM and a similar software configuration to the previous Linux machine. The memory requirements grow linearly with the size of the network. The time required grows slightly faster than linear due to garbage collection overhead (using default GC parameters).
It is not clear that simulating such a large flat ad hoc network is meaningful, except to exhibit SWANS scalability and performance. However, one could certainly simulate many smaller, connected flat ad hoc networks with comparable workload. Regardless, these results far exceed GloMoSim or ns2 capabilities, by approximately an order and two orders of magnitude, respectively. Smaller networks run proportionally faster and in proportionally less memory in JiST than in either GloMoSim or ns2.