sipp: SIPp (SIP test tool)
sipp:
sipp: SIPp is a test tool / traffic generator for the SIP protocol. It
sipp: includes a few basic built-in scenarios (UAC and UAS) and can also
sipp: read custom XML scenario files describing arbitrary call flows.
sipp:
sipp: It supports UDP, TCP, TLS, SIP authentication, RTP replay, and many
sipp: more features.  For more information, see the documentation from:
sipp:     sipp -h
sipp: and the SIPp homepage:
sipp:     http://sipp.sourceforge.net/