Unified number subscriber identity is the provisioned business group line identity where CSTA + unified number call services are provided.
Subscriber identity is where all unified number routing device monitoring and call control is preformed. Depending on the application requirements unified number Identities are provisioned in one of the two following ways:
Registering Device – physical SIP device that registers using the subscribers unified number identify. Applications typically uses the unified number identity as the subscriber's identity. It is possible that no registering device is currently registered or reachable for the unified number subscriber DN. In this case an alternate destination is provisioned, for example using the Call Forwarding - Dependable subcriber feature.Parent topic: Routing and Translation
Non-Registering Device – unified number subscriber identity provisioned when no SIP device ever registers for the Unified number subscriber identity. This unified number subscriber identity is provisioned with SIP subscriber data to permit the customer to purchase a dynamic device license and work as a register device. Applications typically use the unified number identity as a workgroup identity. In this case an alternate destination should be provisioned using the Call Forwarding - Dependable subscriber feature.