[COLUG] Asterisk: Goes through firewalls

[Duane]

jep200404 wrote:
> Rob Funk wrote:
> 
>> ... IAX protocol's NAT-traversing advantage over SIP.
> 
> Thanks for mentioning that NAT stuff. I'd given up on OSS VOIP, 
> because I hadn't heard of any OSS VOIP that would work through 
> stock default configured commodity firewall/NAT/routers. 

News to me, I have Asterisk, I'm such a hypocrite I know :P but only
till I get the time to convert to Callweaver.

The Asterisk I have installed has been more or less up and running since
I started playing with VoIP in 2004 (before other options existed).

Anyways I have Asterisk setup behind a NAT router and do SIP calls all
day long till my hearts content, even with other people running similar
setups with SIP soft switches also behind NAT.

The use of STUN/outbound proxies takes care of all the issues, STUN
works by giving a SIP device/soft phone it's external IP and ports, this
won't work with all NAT routers, but it does for most.

Alternatively you can just use outbound proxies.

If SIP didn't work behind NAT services like voxalot.com and
freeworlddialup would have flopped long ago, not to mention the numerous
commercial VSP offerings that ship out hardware, none of these to the
best of my knowledge uses IAX.

Seems to me the only ones having issues with SIP are early adopters that
don't do enough research on the subject and then come unhinged with one
way audio due to NAT or firewalls.

-- 

Best regards,
 Duane

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"In the long run the pessimist may be proved right,
    but the optimist has a better time on the trip."