SIP 491 Request Pending Error

[wallacezammit]

Hi

I have connected an OXE rel 8.0.1 with a Maverick IVR 2.12. This IVR basically uses
Asterisk SIP Stack 1.4.33.1 to communicate with OXE.

The call received through ISDN on the OXE is directed through sip to the maverick ivr were the maverick does filtering, qeueing and voice recording. The latter will utilise 2sip channels to function. The maverick passes back the call to the OXE and uses the terminals connected to the OXE as endpoints. The maverick keeps the SIP channels open even when call is on the OXE endpoints so to be able to record call.

The problem we are experiencing is that sometimes the sets on the oxe ring, they display the call but when answered no audio is heard. This is especially happening when a call is received ok on the set of the oxe and is then transferred to another set on the same oxe. he other set rings but no audio is heard.

I pointed the SIP error associated with the drop of calls : SIP 491 Request Pending

The PBX and Maverick both send equivalent SIP INVITE at the time of transfer, and if one of the parts does it without first sending an ACK to the other's INVITE, the dialog between the 2 system is no longer possible. Both systems send SIP 491 to each other and the call is dropped in a few seconds.

Does someone know if there is something we can change in the oxe to solve this problem?

Regards
Wallace

[Konstantinos.E]

hi

this behavor means encoding problem.
check codecs on terminals and sip trunks.g 711,g723,g729? do you use ip domains?
with what codec you pass through to the oxe and what codec you give in the terminals?

[wallacezammit]

Yes i saw that it could be codecs, I will check them just in case but this problem happens intermitently even between same sets.

this problem is generated on few calls intermitently. The rest of the calls work fine and are transferred without problems.

It seems that when a call is to be transferred, both maverick and oxe send invites to each other and if one of the parts sends the invite without first sending the ack to the one who generated the first invite then the connection between oxe and maverick falls with SIP491 error - request pending.

I would like to know if in this case I can stop the oxe from sending the invite.

only one domain is used, the default one.

[MrAnMo]

Try to use every communication without compression. So in you ip domain say for intra and extra domain call no compression.

Try to enable sdp in 18x maybe it will help.

Alcatel will tell you to upgrade to a fully supported release like r9.1 or 10 There are a lot of changes since release 8.01.

Goodluck