It could just be the deployments I’ve seen lately; or it could be a telecom vs. server / IT thing. Many / most of the Lync deployments with EV I’ve seen haven’t had intercept messages configured.
Intercept messages advise the caller when their call is unable to be completed, and often the reason why the call cannot be completed. They’re useful in a Lync environment as they tell the caller the reason for the failure. If a caller dials an unassigned number (a number assigned to your organization, live on the trunk) but not assigned to a user without a announcement the caller will likely hear a brief ring-back and then the call will drop. This is undesirable for a number of reasons, I think most importantly without an intercept message callers may think there’s an issue / outage. You can look for occurrences of this in QoE reports. It will appear as an expected error response code 404, Diagnostic ID 1003.
Functionality exists natively in Lync to provide announcements to callers. First we need to create the announcement to play to callers. You can you text-to-speech for the announcement, but I prefer an audio file, as I can include SIT tones at the beginning of the file. I used the sound files (CCPL License) included with Asterisk to build my announcement. The sound files are recorded by Allison Smith, her voice features in IVR and announcements everywhere.
To create the announcement we must first import the announcement audio file with Import-CsAnnoucementFile.
Import-CsAnnouncementFile -Parent ApplicationServer:Server01.example.com -FileName "discon-or-out-of-service.wav" -Content (Get-Content ".discon-or-out-of-service.wav" -ReadCount 0 -Encoding
Then create the announcement with New-CsAnnoucement.
New-CsAnnouncement -Identity ApplicationServer:server01.example.com -Name "discon-or-out-of-service" -AudioFilePrompt "discon-or-out-of-service.wav"
Finally we need to define a number range where the announcement should be played when the number is unassigned. You can use the Lync control panel to create the Unassigned Number Range but it’s straight forward in PowerShell, with New-CsUnassignedNumber.
New-CsUnassignedNumber -Identity Range_1 -NumberRangeStart "+14255551000" -NumberRangeEnd "+14255551100" -AnnouncementService ApplicationServer:Server01.example.com -AnnouncementName "discon-or-out-of-service"
Now when you dial a number that falls in the range configured but is not assigned you should here the intercept message.