SIP Early Offer and CIPC behaviour

[Andrey Vorobev]

I am trying to implement SIP EO on trunk from CUCM to CUBE.
I enabled SIP EO in sip profile (Insert MTP if needed)
To test I use CIPC version 8.6.5.0.
I notice diffirent bihavior when calling from CIPC over SIP trunk.
When I enter number and press DIAL button, I see SIP EO on trunk, SDP is inserted in INVITE.
When I call to same number using REDIAL button, no SDP in INVITE. SIP DO on trunk.
I have tested it with hardware phone (7962).
Same behaviour
So, is it software bug or feature?
It the way to force CUCM insert SDP in both cases?

[Mohammed al Baqari]

Hi,

I suggested tested this on my lab running 9.1(2) and got EO in both cases which is expected. I used deskphone (7945).

It seems to be bug behavior or something I am not aware off. What you described varies between enbloc or digit-by-digit dialing but has no impact on EO or DO

[Andrey Vorobev]

I analized cucm logs.
First picture is message exchange when I press dial button.

Second, when I press dial button.

I use g729 codec on the trunk.

I have tried to create HW_MTP on router for 729 codec, assigned it to phone and trunk, checked MTP required.
No sucess.
I use CIPC-8.5.6.0 and CUCM-10.5.2.12901-1

I do not have the issue when phone has been off-hook state before I press dial or redial button.
The issue exist only when phone is on-hook and I press redial softkey.

I have tested it with my 7962 desktop and got the same issue.

[Mohammed al Baqari]

Hi,

Can you use RTMT and generate session trace. From the ladder diagram you can click on INVITE/200OK messages for both scenarios to see if you are having EO or DO

[Andrey Vorobev]

Hi Mohammed,

Please,  look at diagrams.
Firts -  INVITE w/SDP - EO.
Second - INVITE - DO

[Mohammed al Baqari]

Hi Andrey,

I can see the diagrams but these are from wireshark (if I am not wrong). I would like to see RTMT report to confirm with and without SDP.