We are planning a CER implementation. The documentation states that we need at least one DID for each ERL. However, management thinks it is a short-coming of the CER system if it forces such a requirement. I explained to them about how call-back needs a second DID so that CER can intercept the call and ensure that it gets delivered to the phone with no avail. In our scenario, hundreds of rooms are individual ERLs, so this is a bit of an issue.
Is it at all possible to:
1. Just use the phone's DID as the ELIN for some ERLs, with the understanding that call-back may not work if the phone is in DND mode.
2. Have a CallBack number that differs from the ELIN in the ALI database?
Thanks for your assistance.