Contributions

• David Beckemeyer: http://www.bdt.com/david
  • Per message: http://lists.digium.com/pipermail/asterisk-dev/2004-June/004630.html

Detail

I would really like to have STUN support in the SIP implementation of Asterisk. STUN support would permit an Asterisk system behind a NAT to communicate with external SIP entities. The localnet/externip settings of sip.conf permit Asterisk to operate behind certain types of NATs. However, it requies that the external IP be known and set manually in the Asterisk configuration. More importantly, the localnet/externip settings do not solve the problem of Asterisk. behind a port translating (Full Cone) NAT.

I'd be interested in contributing to development of STUN support for Asterisk, financially, as well as helping test/debug code. I know C, but I have not done productiion coding in a long time. I know the protocols very well and I have access to a lot of hardware and test scenarios for testing.

The best reference model I know of for a good STUN implementation is that contained in the Sipura SPA devices. Watch what they do with STUN to see how a proper STUN implementation should perform.

Contact me: david at bdt.com or post here if you're interested in making this happen.

UPDATE: Karl Brose and David Beckemeyer are taking on this task. Karl is doing the coding and I'm funding the effort (Karl is donating half his time). Work is moving along and we hope to have something to release for testing in mid to late July 2004.

Background

• STUN
• SIPURA SPA-2000
• Asterisk SIP NAT solutions

Resources

• Sourceforge STUN client library
• CallWeaver is an Asterisk fork that include STUN client basic capabilities for chan_sip so if you are experiencing problems with your asterisk server behind NAT, try to use it and you are likely to solve your problems.

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Asterisk bounty