Unity Connection With AAR

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Mar 26th, 2010
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Our customer has decided now to route calls across the WAN and the 5th call to most sites will reroute via the PSTN using AAR. This creates a new problem for us. How do we ensure that if an external caller calls a remote site DN (via a remote PSTN gateway) and are forwarded to the centralized Unity Connection server back out via the PSTN that the call is not dropped?

My understanding is that there is an external phone number mask on each voicemail port and an AAR Groups/CSS.

We believe that an acceptable solution would be to route the rerouted AAR calls to a generic call handler (possibly with a greeting) which transfers to the operator in the central site. The operator can then deal with the call accordingly (by this time more bandwidth may be available).

This creates the question of how to configure the external phone number mask on the voicemail ports. Does each port need a specific DDI or would the external phone number mask only need to be configured on the Unity hunt pilot? What is the purpose of having individual external DDIs on each port?

Any help would be greatly appreciated



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Tommer Catlin Fri, 03/26/2010 - 08:02
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I would think if you create the CTI route points with the DID of what it was routing it would still work with AAR right?

If a remote site incoming call is 650-555-1212, CUCM picks up the route 1212 from the incoming call.

1212 is the CTI route point into CUC

CUC has the callhandler 1212

Call Handler is played.

For AAR, its only a trigger to say there is more bandwidth, reroute the call from remote site to xx (or number of calls)

So 650-555-1212 is rerouted based on a DN that it leaves.   I dont think it will use the DN or the Unity voicemail port as the caller ID.

If it did, then yes, you have to use some sort of generic callhandler.    

BUT... AAR should still work for Unity the same as it would for an IP phone at the remote site, the second it tries to roll the call to Unity, SS7 should pickup there is no bandwidth, rereoute to PSTN, ring your incoming at the hub to Unity and play the ip phones personal greeting.

Unless I have something backwards here.

I think what happens is that it acts as a call forward on AAR and changes the caller ID.   Take for example when you place your IP phone on CFWD to your cell phone, and run a isdn debug q921 and 931.   If you look closely at the numbers, CUCM is masking the numbers outbound for you.

The only problem is that if you have a provider with these new "soft switches" which require you to use your assigned DID to the outbound trunk.  If it is anything else, it will reject the call. (search TelePacific in the forums, I posted something on this).   Most providers are supposed to fix this, but I have not heard if its

Damian Heavey Fri, 03/26/2010 - 08:59
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Hi there, when you say CTI route point do you mean the hunt pilot for the Unity Voicemail pilot?

Thanks for the reply, let me simplify what I am asking and also mention that outbound CLI is disabled at the remote site...

Unity Connection located at central HQ

4 calls are active from site A across the WAN already which is the maximum for this location

PSTN Caller dials 0207 555 1001 (internal DN 1001) at site A

DN 1001 does not answer and is set to CFWD no answer to Unity

CM sees there are 4 calls active and does not allow the call to cross the WAN to Unity

At this point AAR should kick in for the call to Unity and the PSTN caller should be tromboned back out over the PSTN to HQ. We want this just to go to a generic greeting which is preferable to the call just disconnecting. We don't care about going to the correct mailbox at this point (we probably can't anyway as there is no outbound caller ID enabled on this ISDN line).

My question is simply do we need to enable the external phone number mask on the hunt pilot or on each individual voice port and what are the advantages of each option? Also if it is necessary to do this on the port level then would we need 48 DDIs to match the number of ports?

Thanks -  I hope this makes the situation easier to understand!


Marwan ALshawi Sat, 03/27/2010 - 04:26
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if you don't care about sending the call to the right mail box when its go over PSTN then its simple

in the CUC CTI route point in CCM assign the required AAR group ( witht correct pstn access digit such as 9 or 0 ) and it has to have the correct CSS for PSTN access using the remote site GW

you can use external number mask or in your case i thin its better to use the AAR number mask which you will find it in the DN setting of the CTI

put the full PSTN number that needed to be dialed ( which supposed to be a DID to the CUC or to another CTI>>call hander ) based on your design

good luck

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