[OpenSER-Users] stun

Aymeric Moizard jack at atosc.org
Tue Jun 10 17:49:22 CEST 2008



On Tue, 10 Jun 2008, David Villasmil wrote:

> True (about getting the IP from the register), but that's putting more
> processing on the server, I'd rather let ths UAC do the ip resolution when
> we're talking thousands of clients (Which I am)

The behavior I described is made on the client/endpoint which look at
the received and rport in the answer to a request sent to the server.
(and this is not a DNS resolution: this is just "looking at"...)

The server in this case don't have any processing to do anymore: he always
receive the correct contact header.

No need for STUN to have a correct IP/port for SIP even behind symmetric 
NAT. ;)

tks,
Aymeric MOIZARD / ANTISIP
amsip - http://www.antisip.com
osip2 - http://www.osip.org
eXosip2 - http://savannah.nongnu.org/projects/exosip/


> Cheers
>
> On Tue, Jun 10, 2008 at 1:59 PM, Aymeric Moizard <jack at atosc.org> wrote:
>
>>
>> Stun can work even behind symmetric NAT if the stun server was
>> running on the same socket the SIP server is running... I hope
>> this feature will come soon!
>>
>> I can help with this.
>>
>> Also, SIP don't need to use STUN to work: you can discover your
>> IP address and port very easily by looking at the REGISTER answer
>> or OPTIONS answer which contains the "received" and "rport"
>> parameter.
>>
>> Of course, symmetric NAT are a nightmare for RTP, but not for SIP...
>>
>> tks,
>> Aymeric MOIZARD / ANTISIP
>> amsip - http://www.antisip.com
>> osip2 - http://www.osip.org
>> eXosip2 - http://savannah.nongnu.org/projects/exosip/
>>
>>
>>
>> On Tue, 10 Jun 2008, Iñaki Baz Castillo wrote:
>>
>>  El Tuesday 10 June 2008 10:44:51 Ali Jawad escribió:
>>>
>>>> Hi All
>>>>
>>>> I had a lot of problems with STUN and symmetric NAT. The thing is that
>>>> it does not always work with symmetric NAT. That would be mostly routers
>>>> based on Linux IPTABLES.
>>>>
>>>
>>> STUN **CANNOT** work with symetric NAT. The NAT router maps the internal
>>> port
>>> with a different public port *depending* on the destination IP:port, so
>>> STUN
>>> can't work.
>>>
>>> --
>>> Iñaki Baz Castillo
>>> ibc at in.ilimit.es
>>>
>>> _______________________________________________
>>> Users mailing list
>>> Users at lists.openser.org
>>> http://lists.openser.org/cgi-bin/mailman/listinfo/users
>>>
>>
>> _______________________________________________
>> Users mailing list
>> Users at lists.openser.org
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>>
>>
>


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