Re: [Ekiga-list] Ekiga.net account with Android 2.3.4 native SIP-client

[Jānis Rukšāns <thedogfarted gmail com>]

(Bringing this back to the mailing list)

On Tue, May 24, 2011 at 11:11 PM, Bart Vandewoestyne
<Bart Vandewoestyne telenet be> wrote:
> OK.  The tcpdump I did with my android phone is online at
>
> http://www.kuleuven-kortrijk.be/~bartv/android.pcap
>
> I've configured 4 SIP accounts and they all try to register.
> These are my findings:
>
> 1) For you server, I see a 400 Bad Contact address server
> response, and as I understand it, this is because of the private
> IP in the Contact header in the REGISTER message.
>
> 2) registration for sip.poivy.com and sip.diamondcard.us seem to
> work, even with the private IP in the Contact header.

Right.

> 3) registration at ekiga.net fails, server returns a 606 Not
> Acceptable, probably because of the private IP in the Via header.

First one ("unregister others") because of the Via, the second because
of the Contact. Your previous ekiga.net trace was missing the second
REGISTER message, which led me to believe that Via was the main fault.

> My main questions are:
>
> * Do you see a bug in the Android 2.3.4 client?  Can it send
>  REGISTER messages with private IP's in the Via and Contact
>  header or is this not allowed?

>From the traces it looks like it doesn't support any way to traverse
NAT. It is not really a bug, but rather important missing feature,
something they should do. IPv6 is not going to take over IPv4 any time
soon, and there are other good reasons to use NAT (eg. my provider
charges me for each public IP).

> * Is ekiga.net wrong by returning the 606 Not Acceptable?
>
> If ekiga.net is wrong, I still feel we should try to convince the
> ekiga.net admins to make it work... it will be a big step forward
> for Ekiga on the Android/mobile market.

Technically ekiga.net is wrong about the Via (but not Contact), but
with no NAT support in phone (either classic STUN or ICE, or
whatever), it doesn't make any difference to you. As Damien told in
another post, you will experience audio problems (almost certainly).


But the cool thing about SIP is you're not tied to a single provider.
You can call anyone with a SIP address no matter what your provider
is. If the phone has no NAT support, there are multiple providers with
media relay, select the one(s) you like, and configure to use their
outbound proxy. At least audio should work fine.

Cheers
-- 
Ian