- The box labeled as "Public IP is constant" should read "Public IP and Port are constant" (imho).
References:
http://en.wikipedia.org/wiki/Network_address_translation
http://www.crfreenet.org/~martin/referaty/stun/naty.pdf
http://tools.ietf.org/html/rfc3489 <-- The figure seems to be inspired by this one (figure 2 in section 10.2). The figure there also says "IP", but the explanation of the figure (10.1) says:
If the IP address and port returned in the MAPPED-ADDRESS attribute are not the same as the ones from the first test I, the client knows its behind a symmetric NAT.
So the figure would be much more correct if it said "IP and Port".
