[Freeswitch-dev] Call to registered phone behind NAT

Trixter aka Bret McDanel trixter at 0xdecafbad.com
Mon May 24 12:55:52 PDT 2010

On May 24, 2010, at 12:32 PM, Brian West wrote:

>  in the end your busted sipdroid should learn to overcome nat on its own.

Ideally yes, everything will be proper in what it sends, however there is:

The Robustness Principle: "Be liberal in what you accept, and conservative in what you send" is particularly important in the Internet layer, where one misbehaving host can deny Internet service to many other hosts.
(from RFC1122 and this principle originated in RFC790 and is a Jon Postel founding principle).

It is easy to just say that the other end should be fixed, there are enough software titles that do that  already and end up not working well.  I bring this up because I am chasing down the exposure of a bug in other VoIP software that used to not be present in a them->FS exchange but tightening of the FS code on what it accepts exposed the bug.  So when it starts to get discussed that the other side should fix itself, I feel it important to bring this internet founding principle up.

Trixter aka Bret McDanel

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