1. A firewall test method for testing a firewall implemented in a gateway device including a processor, the gateway device being positioned between a trusted network zone and an untrusted network zone, the method comprising: coupling said gateway device to a first test device, the first test device including at least a first communications session traffic generator, said first communications session traffic generator including means for generating, maintaining, and terminating communications sessions according to a predetermined test plan; operating the first test device to maintain a constant session signaling load through said firewall; operating the first test device to apply a plurality of different rates of session signaling change to said firewall while said constant session signaling load is maintained; monitoring at least one of a CPU utilization rate and a pinhole closing delay in said firewall for each of the plurality of different rates of communications session change to determine at least one of the rate of CPU utilization for each of said plurality of different rates of communication session change and the pinhole closing delay for each of said plurality of different rates of communication session change; and outputting dynamic firewall loading information obtained from said monitoring.