Port Numbers for Nokia VoIP SIP Client

[stevenm]

Hello,

Would anyone know if you change the SIP Proxy Port from the standard 5060 to some other value, does this also change on the client side or does it remain at 5060?

If yes, does anyone know if there is a setting to make the SIP Proxy dest/source ports different?

At this stage I do not have a handset to check this out, and the documentation is not clear about this.

Thanks,

Steve

[Sorcery-ltd]

Hi Steve,

I'm not sure I completely understand your question but there are settings for the Proxy Server within the SIP profiles on 3rd edition phones and you can change the port to anything you want. There aren't separate dest/source ports though, as far as I know it is only the server side that configuration changes for.

If you change your proxy server so that it is listening on a different port than 5060 you will of course have to change the setting in the client.

Hope that helps,
Sorcery

[stevenm]

Hello Sorcery,

Thanks for your reply.

I think that I should explain the reasoning for my question.

From what I can find out, the Nokia VoIP SIP cleint requires the SDP to be included in the INVITE message receiving a SIP call. Unfortunately the flavour of SIP our Server uses does not do this, the SDP information is done later in the call setup, after answer.

I then look and the possibility of writing a "new" SIP client, but without access to the needed API's and the scope of the work needed I ruled this out.

I then had the idea that I may be able to write a SIP "Fixup Agent" that is installed on the phone. To make this a workable I think that I would need to,

1/ Have Agent start on boot - I think that can be done.
2/ Have app run in background like daemon - I think can be done
3/ SIP Signaling port numbers - Here is the issue

The idea is that my app would listen port 5061 for Nokia client and then send modified messages to SIP Server on 5060. (The port number on the SIP server side could also be someting else) This is ok so far.

Then SIP server would send back to my app on 5060.

But now I need to send back Nokia client on a different port number than 5061 as I would think that two apps listening on the same port is a no no.

If there was a way to do this then one could very easy modify the behavour of the Nokia VoIP client without needing access to API's and other issues of speech delay etc.

Anyway, the idea sounds ok but I need to confirm the SIP port issue before I get too carried away....

I hope that this makes sense?

If not, then I will try again.

Steve

[stevenm]

Hello All,

I have been able to get hold of a handset to test.

When the SIP proxy port is changed from 5060 to something else, the source port remains set to 5060. Refer to capture.

Frame 12 (449 bytes on wire, 449 bytes captured)
Ethernet II, Src: NokiaDan_6a:f7:03 (00:15:de:6a:f7:03), Dst: Nec_16:34:58 (00:30:13:16:34:58)
Internet Protocol, Src: 192.168.0.232 (192.168.0.232), Dst: 192.168.0.111 (192.168.0.111)
User Datagram Protocol, Src Port: 5060 (5060), Dst Port: 5065 (5065)
Session Initiation Protocol
Session Initiation Protocol (SIP as raw text)
REGISTER sip:192.168.100.200 SIP/2.0\r\n
Route: <sip:192.168.0.111:5065;lr>\r\n
Via: SIP/2.0/UDP 192.168.0.232:5060;branch=z9hG4bK6d81lc7hh5hc7jbmmg2un31\r\n
From: <sip:3476@192.168.0.111>;tag=akjhlc6sr1hc74immg2q\r\n
To: <sip:3476@192.168.0.111>\r\n
Contact: <sip:3476@192.168.0.232>;expires=3600\r\n
CSeq: 1287 REGISTER\r\n
Call-ID: tLwqI4n_oIduGHg5pFtg3i5IuwraGG\r\n
Supported: sec-agree\r\n
Max-Forwards: 70\r\n
Content-Length: 0\r\n
\r\n

Thnaks

Steve

[Sorcery-ltd]

Hi,

I understand your problem and original question perfectly now. Looks like you are a bit stuck

What about changing the server?

I guess that's not an option.

Sorry I can't help any more.

Sorcery

[stevenm]

Hello Sorcery,

As the phone is able to have a different source / destination ports for the SIP proxy (even though source is set to 5060), I think that it may work. I will at least give it a go.

Although this is a bit of a work around / hack, I think that in some ways it will ok.

As it will be using the Nokia client, I will get the same UI / features etc. As we want to integrate it in to a corporate voice network, I will be able to modify the dialled digits where needed, ie add "0" for PSTN access. I should also be able to make the app look for a backup SIP proxy in the case that the preferred one is not reachable, voice mail integration, etc

Also, I wonder that, as it is not that easy to get the API's needed to write a VoIP client from scatch, could one write an app that would do a complete protcol conversion from SIP to something like Skype? I not sure about this as I do not know anything about the Skype signaling protocol.

Anyway, I am sure that I will "enjoy" to learn C++ on symbian...

Steve