[Users] UA behind NAT puts public IP in Contact, Via - help

[Arek Bekiersz]

Hi Bogdan,


Thanks for all the help.

Bogdan-Andrei Iancu wrote:
> Hi Arek,
> looking on the signalling, you cannot detect the call as nated from 
> proxy point of view, so there is not much you can do. It's a typically 
> situation where the the phones tries to perform nat traversal on its 
> sides but does not do a complete job, preventing also the proxy to do it :(



So what is your final advice about how to speak with German vendor?

They are not violating RFC, but clearly, ther device will NOT work with 
SER or OpenSER in NAT-traversal scenario.

They say to us everytime that they "sold approx. 2 milion of those boxes 
and nobody, no ISP complained". I do not believe at all - this is DSL 
router/modem, so maybe they talk about non-VoIP and VoIP boxes together. 
But you will never know, this is marketing talk..

They say that "ITU-T has given them an approval. This approval described 
that they are fully compatible with the RFC´s for VoIP". Well, yes, they 
do not break RFC. But one flavour of this device is an ATA box, without 
DSL modem. Majority of my customers will buy this ATA to use with 
existing DSL router, cable modem/router or such. They WILL have 
unfriendly NAT there, so what is the sense of ATA box?



-- 
Regards,
Arek Bekiersz