[Yxa-devel] Changing transport to TLS/TCP

[Johan Vikman]

Hi Fredrik,

Of course, below I describe one way this could happen, the yxa stack is used in the LRF node.

  UE                          E-CSCF                                                                          LRF       PSAP
1 |--SIP INVITE TCP-->|                                                                                     |              |
2 |                                     |--SIP INVITE TCP    -->                                            |              |
3 |                                     |<-- SIP 300 Multiple Choices using TLS/TCP -- |              |
4 |                                     |--SIP INVITE TLS/TCP------------------------------------------->|
5 |                                     |--200 OK --------------------------------------------------------------|
6 |<--- 200 OK -----------|                                                                                     |              |

1. UE calls 112
2. E-CSCF does not know which PSAP to forward to, so it asks LRF
3. The LRF knows where the UE is and knows that for this case a PSAP using SIPS is configured for that area, and also that a location should be provided.
     Because the PSAP is uing SIPS, the LRF has to use TLS/TCP for the response.
4. E-CSCF forwards SIP INVITE to PSAP
5. PSAP 200 OK to E-CSCF
6. E-CSCF 200 OK to UE

My problem here is at message #3, the response back to E-CSCF, I do not know how to make yxa use TCP/TLS instead of TCP, or even if it is allowed to change transport in this fashion.

/Johan

On Sep 2, 2013, at 12:01 PM, Fredrik Thulin <fredrik at thulin.net> wrote:

> On Mon, 2013-09-02 at 11:20 +0200, Johan Vikman wrote:
>> Hi,
>> 
>> I am using the yxa stack to provide Geolocations over SIP.
>> 
>> I now have gotten a requirement that says that if the Geolocation ultimately will be sent to a contact using sips, I need to respond to the request using TLS/TCP, i.e. respons to a TCP  request using TLS/TCP.
>> 
>> The reason is amongst others to hide the location, if I understand the requirement correctly. 
>> 
>> Are there any support for this in the yxa stack?
>> 
> 
> Sorry, I don't really follow your use case. Can you show how the
> geolocation querying using SIP works in an example request/response
> flow?
> 
> YXA supports SIPS with TLS over TCP, but I don't really understand your
> question I'm afraid.
> 
> /Fredrik
> 
>