1. A method of testing a firewall comprising: transmitting at least one of a session initiation signal to initiate a communications session through said firewall and a session termination signal used to termination an established communications session; and monitoring to determine from the time of at least one transmitted signal at least one of a port opening delay which occurs in regard to opening a port in said firewall for a communications session that is being initiated and a port closing delay which occurs in regard to closing a port in said firewall when terminating an established communications session.