Michael Stilmant wrote: here you are http://www.fokus.gmd.de/research/cc/glone/projects/ipt/ http://www.tsufl.edu/williams/Projects/InternetPhone/TSCIS445.htm http://www.cis.ohio-state.edu/~jain/refs/ref_voip.htm
See also http://www.cs.columbia.edu/sip http://www.cs.columbia.edu/~hgs/internet -- Henning Schulzrinne http://www.cs.columbia.edu/~hgs