Main Number Handling – PSTN number as a Response Group IVR Destination

In my last post, I covered how to have a Response Group Queue overflow/timeout action send a call to a PSTN number. That means you can send a call to an analog phone (maybe a cordless one), a mobile, or any other PSTN number. That’s awesome for overflow and timeouts, but there’s still a hole in Response Group functionality: how can an IVR option deliver a call to a PSTN destination?

Every once in a while, you need to get creative in your solutions to meet end-user requirements. The solution here is tricky to figure out, but simple to configure once you know what to do.

To review, a Response Group IVR is when someone calls a workflow number, hears options, and presses a corresponding key. The native workflow options are to deliver the call to a Queue, or to ask another series of questions. There is no option to deliver a call to a PSTN number.

If we look deeper at the Queue configuration, the only place to specify a PSTN number is in the overflow and timeout options. If we could set the workflow to deliver a call to a Queue, and set the Queue to overflow immediately to a telephone number, we’d be set. We can do that by setting the Maximum number of calls in the Queue configuration to zero:


And if you try the call, it will not work. As it turns out, a Queue will error out if there is no Group assigned to the Queue. The fix is simple: create a user in AD, enable them for SfB and enable Enterprise Voice, create a new Response Group group and assign the new user as an Agent. Assign that Group to the Queue:

Group in Queue

And things will work – a call to the IVR, where the caller selects the option for the mobile number, will be forwarded to that mobile phone immediately. The Queue process throws an error when it see there isn’t a Group with at least one Agent assigned, it never gets far enough in the process to look at the overflow options.

I don’t recommend that you use a real user’s SfB account for this. Create a fake account, and make sure you add comments or notes to indicate the purpose of the account, so that it’s not deleted or changed.

If you’re going to use this solution for a number of different workflows, you can use a more generic name for the User and Group, and use the same User and Group for all the Queues, as the destination is configured in the Queue.



Main Number Handling – Putting it all Together, Response Group Calls to a non-SfB number

A few years ago, I worked with a two different organizations who had the same scenario.  They had a main number for the security department. This number was for a Response Group Workflow, which would ring the security staff and a couple of additional phones in the security area, such as the break room.

That worked well when there was someone in the security office to answer the call, but it meant that calls would go to voicemail if there were no security staff in office. This happened often, especially in the one organization that was closed at night and the security staff member had to do patrols.

The solution for both was to setup the Response Group Queue timeout and overflow actions to “forward to telephone number”:

call action PSTN

Note the formation for the telephone number – you need to enter it as if it’s a SIP address, with your SIP domain after the @.

Yes, all of my lab environment domain names are colors! I set the desktop background of all the servers to be the domain name color, which helps me stay straight on which environment I’m connected to.

Okay, that’s cool, we can forward calls to a mobile or analog or any other phone as a timeout action on a queue. Tune in next blog post, where I show you how to send a call to any PSTN destination from a Response Group IVR.

Main Number Handling – Putting it all Together in Large Offices, reception coverage

In the previous post, I covered how to have a receptionist have first kick at answering a call, then for the call to be handled by an Auto Attendant if they weren’t available. You might want to have a backup for the receptionist if they’re not able to answer the phone. The easy solution is to also add this person to the Response Group group as an Agent. The trick here is to specify the two agents, and set the Routing Method to Serial in the Group configuration:

Serial Agents

Wit this setup, calls will always first ring “AApple”, then after the Alert Time has expired, the call will go to “BBlueberry”, and finally to the overflow destination. Be sure to watch your Queue and Group timers as discussed here to make sure your call doesn’t bounce around between the users.

This solution works well if you only need a main person and one backup. If you need a main group and a backup group, you would configure two groups, and then create an ordered list in the Queue settings:

Reception Queue

Make sure that the sum of the Group timeout values equals the Queue timeout value, otherwise your call with ring “Reception_Main”, then “Reception_Backup”, and then “Reception_Main” again. For example, I might set the Reception_Main group to 10 seconds, the Reception_Backup group to 15 seconds, and the Queue timeout to 25 seconds.

You can include the users in the “Reception_Main” group as agents in “Reception_Backup” if you want the users in the main group to be able to answer the call if it’s ringing the backup group.

I’ve seen this approach used for a shipping/receiving door buzzer. The driver pushed the door buzzer, which automatically dialed the Response Group (this behaviour was configured in an AudioCodes MediaPack). The Response Group had the shipper/receiver as the main group, and then some other nearby staff who could act as their backup.

Up next: Sending a call from a Response Group to a PSTN or other PBX phone

Main Number Handling – Putting it all Together in Larger Offices

I previously covered some simple solutions for main number handling for smaller offices. Now let’s have a look at larger offices.

I’ve worked with several organizations that prefer a human voice answer the phone wherever possible, and when that can’t happen they would allow the call to handled by an Auto Attendant.

The simplest way to configure this is to have the main number be a response group workflow. The receptionist is added as an agent. In the Queue, set the timeout (and optionally the max calls) overflow destination to the SIP address of your Auto Attendant. Callers now ring the agents when they first call, and then get the Auto Attendant if no agent can take their call.

Up next, some scenarios where you might want to add a second group of agents.