locked
OCS CUCM Call disconnect delay RRS feed

  • Question

  • We are currently using OCS 2007 and Call Manager 7.0.1 and have linked them via SIP trunk. All the outisde calls come in via CUCM and ring appropriately on OCS side. All the features are working properly, but i have noticed couple of things from end user experience side and wanted to check if anyone had any suggestions for it.

    1) When call comes in and rings both deskphone (CUCM) and OCS client and call is picked up up via OCS, it shows call is active on the deskphone too. But when call is disconnected from OCS, it takes about 6-8 seconds on CUCM side to terminate the call. During this 6 - 8 second the user on other side will hear the hold music from call manager and then call is disconnected. Any suggestions on how can i make this 6-8 seconds to maybe 1-2 seconds ?

    2) When someone from OCS calls someone internal with their full DID (+XXXXXXXXXX) and call is routed by OCS mediation server to OCS client only and not to deskphone. I guessing this is because call is handled by enterprise voice and not send via sip trunk. The only way around it i can think is using simultaneous ring(SR) on OCS client and ring my deskphone. But that creates a loop for any calls coming from outside on CUCM (CUCM->OCS(SipTrunk)->CUCM (SR)->OCS(Sip Trunk)). Any other suggestions around this ?

    I am trying to make end user experience better before we roll this out to everyone.

    Thanks
    Varun
    Tuesday, December 29, 2009 4:41 PM

Answers

  • Hi Varun,

     

    You have arrived at a very interesting couple of points with your configuration. For point one you should be able to change this somewhat but how low you can go is something you will have to work on. The whole point of having the line stay active in CUCM on the IP phone is so you can transfer the call back to your IP phone without dropping the call. You should be able to lower this value in the End user configuration window in CUCM.

    http://www.cisco.com/en/US/docs/voice_ip_comm/cucm/admin/7_1_2/ccmcfg/b08user.html#wp1153074

    The Maximum Wait Time for Desk Pickup setting on the End User Configuration window determines the amount of time the call remains on hold after the hang-up at the remote destination. The default specifies 10000 milliseconds (10 seconds).

     Your second point is another matter. Unfortunately due to Cisco and Microsoft not implementing dual call forking there is no way for the system to let each other know that they are calling each other with the same phone number therefore no loop prevention in the situation you speak of. You have to choose where to implement the sim ring feature but you can’t do it in both. Unfortunately Unified Mobility doesn’t allow you to selectively choose when to enable the feature on inbound caller id so it will ring all your destination phones no matter who is calling you. It would be call if it could but it cant and seeing as MS and Cisco never implemented true dual call forking your stuck with what you currently have.

    I would recommend the following.

    - Use sim ring on the system that has the incoming PSTN access to ring the alternate phone. So if CUCM currently has all your PSTN access use CUCM to ring OC using unified mobility.

    -on the system that has no PSTN access other than the PBX tie trunk use it to ring a cell phone so at least it has an alternate number that can reach the user.

     -I wouldn’t recommend splitting direct PSTN access between both systems in this case where you are trying to sim ring both OC and Cisco IP phone just to keep it simple and avoid looping issues. Use one or the other for PSTN access till you can move away from this scenario of dual ringing phones. I think in the end once your users get used to OC they will more than likely stop using the IP phones or use it very little especially if they can sim ring a cell phone from OC which ends the argument of when I am not logged on how do I get my calls.

    Cheers

    Chris

     


    http://voipnorm.blogspot.com/
    • Marked as answer by Varun81 Wednesday, December 30, 2009 9:19 PM
    Tuesday, December 29, 2009 6:14 PM

All replies

  • Hi Varun,

    I'm not a CUCM expert so I can't comment on the item #1.

    Regarding the item #2. It seems that you have configured the Simultaneous Ringing on the CUCM side to make both Deskphone and Communicator ringing at the same time for an incoming call. This configuration is just a "half" Dual Forking. This configuration allow only CUCM to fork the call to the 2 endpoints (CUCM deskphone and Communicator). But it will not do the job for the other direction:
    Indeed, when you are initiating a call from the Communicator, OCS will perform the RNL (Reverse Number Lookup) and will fork the call ONLY to OCS endpoints (Communicator, Tanjay telephone...) but it will NOT fork the call to your CUCM. Therefore, your CUCM deskphone will never ring.
    I'm sure that Dual Forking is not certified for CUCM but heard that it is "working???" for CUCM 7.x so you may make a try to configure your OCS user to be a "real" Dual Forking user by:
     - Checking the "Enable PBX integration" 
     - Keeping the field "Server URI" to blank

    With this configuration, OCS will fork the call to your CUCM deskphone for a call making from Communicator. But at the same time, you may already know that if you configure your user with Dual Forking, this will prevent you to use some OCS features such as Simultaneous Ringing, Team Call...

    -QD
     

    Tuesday, December 29, 2009 5:27 PM
  • Hi Varun,

     

    You have arrived at a very interesting couple of points with your configuration. For point one you should be able to change this somewhat but how low you can go is something you will have to work on. The whole point of having the line stay active in CUCM on the IP phone is so you can transfer the call back to your IP phone without dropping the call. You should be able to lower this value in the End user configuration window in CUCM.

    http://www.cisco.com/en/US/docs/voice_ip_comm/cucm/admin/7_1_2/ccmcfg/b08user.html#wp1153074

    The Maximum Wait Time for Desk Pickup setting on the End User Configuration window determines the amount of time the call remains on hold after the hang-up at the remote destination. The default specifies 10000 milliseconds (10 seconds).

     Your second point is another matter. Unfortunately due to Cisco and Microsoft not implementing dual call forking there is no way for the system to let each other know that they are calling each other with the same phone number therefore no loop prevention in the situation you speak of. You have to choose where to implement the sim ring feature but you can’t do it in both. Unfortunately Unified Mobility doesn’t allow you to selectively choose when to enable the feature on inbound caller id so it will ring all your destination phones no matter who is calling you. It would be call if it could but it cant and seeing as MS and Cisco never implemented true dual call forking your stuck with what you currently have.

    I would recommend the following.

    - Use sim ring on the system that has the incoming PSTN access to ring the alternate phone. So if CUCM currently has all your PSTN access use CUCM to ring OC using unified mobility.

    -on the system that has no PSTN access other than the PBX tie trunk use it to ring a cell phone so at least it has an alternate number that can reach the user.

     -I wouldn’t recommend splitting direct PSTN access between both systems in this case where you are trying to sim ring both OC and Cisco IP phone just to keep it simple and avoid looping issues. Use one or the other for PSTN access till you can move away from this scenario of dual ringing phones. I think in the end once your users get used to OC they will more than likely stop using the IP phones or use it very little especially if they can sim ring a cell phone from OC which ends the argument of when I am not logged on how do I get my calls.

    Cheers

    Chris

     


    http://voipnorm.blogspot.com/
    • Marked as answer by Varun81 Wednesday, December 30, 2009 9:19 PM
    Tuesday, December 29, 2009 6:14 PM
  • Hi Varun,

    I'm not a CUCM expert so I can't comment on the item #1.

    Regarding the item #2. It seems that you have configured the Simultaneous Ringing on the CUCM side to make both Deskphone and Communicator ringing at the same time for an incoming call. This configuration is just a "half" Dual Forking. This configuration allow only CUCM to fork the call to the 2 endpoints (CUCM deskphone and Communicator). But it will not do the job for the other direction:
    Indeed, when you are initiating a call from the Communicator, OCS will perform the RNL (Reverse Number Lookup) and will fork the call ONLY to OCS endpoints (Communicator, Tanjay telephone...) but it will NOT fork the call to your CUCM. Therefore, your CUCM deskphone will never ring.
    I'm sure that Dual Forking is not certified for CUCM but heard that it is "working???" for CUCM 7.x so you may make a try to configure your OCS user to be a "real" Dual Forking user by:
     - Checking the "Enable PBX integration" 
     - Keeping the field "Server URI" to blank

    With this configuration, OCS will fork the call to your CUCM deskphone for a call making from Communicator. But at the same time, you may already know that if you configure your user with Dual Forking, this will prevent you to use some OCS features such as Simultaneous Ringing, Team Call...

    -QD
     


    If you are to follow Quang's advice you will need to unconfigure what you have done in CUCM with unified mobility other wise you will end up with a routing loop. Although this OCS configuration may work it is not support by MSFT for CUCM and if you are to raise a support ticket the first thing they may ask you to do is remove it. Below is the link to the OIP certification page and only the Nortel CS1000 is certified for dual call forking.

    http://technet.microsoft.com/en-us/office/ocs/bb735838.aspx

    Like I said in my previous post in the case with CUCM you have to choose where you want to do this type of interop and take the good with the bad.

    Cheers
    Chris

    http://voipnorm.blogspot.com/
    Wednesday, December 30, 2009 2:53 AM
  • Varun81, I would be forever in your debt if you could share with me your CUCM 7.x <-SIP-> OCS integration configurations. I can with without issue have CUCM 7.1(3)SU2 <-> OCS 2007 R2 calls across a SIP trunk (using mediation server). I can even get CUCM and EUM working for VM.

    What I can never get working is an incoming PSTN call via CUCM to terminate on the MOC client (route pattern send call to MOC via SIP trunk). I can get the MOC cleint to ring, but when i answer the call using MOC the call drops and the caller gets fast busy.

    Can you help?

    Thanks

    nzan69

    Thursday, March 25, 2010 1:54 AM