This was for AMTMitelCRE recordings with a Mitel PABX over a SIP trunk.
SOLUTION:
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On the Mitel I have a timer in which I can adjust this:
Keep-Alive (OPTIONS) Period 120
The invite is coming from the gateway on the outbound calls and we need your assistance in this regard.
According to Leon this can be caused by your SIP provider as well.
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_ It appears Mitel prefers UPDATE method instead of Re-INVITE for session refreshes
_ The M3k is setup to use Re-INVITE instead of UPDATE method, as a global setting
_ On an outbound call from Mitel with session-expires=90 Min-SE=90, we answer the call with 200 OK. We send a session refreshing Re-INVITE after 45 seconds with our RTP port unchanged (half way through the session expires limit of 90 seconds, as per RFC 4028 recommendation) and Mitel responds with a 200 OK with SDP showing a change of RTP listening port on the server 172.16.241.41. This change of RTP port causes Mitel recording system to creating a new recording instance of the same call (i.e. same Call-ID)
As a resolution we advise the below options in order:
- 1. Mitel sets up their system such that it does not change RTP ports for a Re-INVITE response
- Increase M3k Session-expires and Min-SE values to 1800 seconds (30 mins) as per RFC 4028 recommendation or more.
P.S. the Mitel will still change RTP ports on a session refreshing Re-INVITE for calls longer than 15 minutes - Change the M3k session refresh method to UPDATE. This will affect calls to other SIP entities like Lync on the M3k
- Change the M3k to SBC mode from IP2IP mode. I will confirm the risks with the experts from HQ
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Lync supports UPDATE method.
You may add the parameter on AdminPage:
SessionExpiresMethod = 1