Virtual SNR DN Configuration in Cisco IOS Router | CCIE Collaboration Exam Answer

E.

-> Virtual SNR DN only supports Cisco Unified SCCP IP phone DNs.

-> Virtual SNR DN provides no mid-call support.

Mid-calls are either of the following: "" Calls that arrive before the DN is associated with a registered phone and is still present after the DN is associated with the phone.

"" Calls that arrive for a registered DN that changes state from registered to virtual and back to registered.

-> Mid-calls cannot be pulled back, answered, or terminated from the phone associated with the DN.

-> State of the virtual DN transitions from ringing to hold or remains on hold as a registered DN.

References: http://www.cisco.com/c/en/us/td/docs/voice_ip_comm/cucme/admin/configuration/guide/cmeadm/cmesnr.html.

A virtual SNR (Single Number Reach) DN (Directory Number) allows a user to receive calls on a device other than their primary phone. When a call comes in to the virtual SNR DN, the call can be simultaneously routed to one or more other devices, such as a mobile phone, home phone, or another office phone. The first device to answer the call "wins," and the other devices stop ringing.

Of the given options, the statement that is true about a virtual SNR DN-configured Cisco Unified Communications Manager Express-enabled Cisco IOS router is:

D. The SNR feature can only be invoked if the virtual SNR DN is associated with at least one registered IP phone.

This means that in order for the SNR feature to work, the virtual SNR DN must be associated with at least one registered IP phone. The virtual SNR DN acts as a forwarding number, and if it is not associated with any registered IP phones, calls to the virtual SNR DN will not be forwarded to any other devices.

Option A is incorrect because a virtual SNR DN can support both SCCP (Skinny Client Control Protocol) and SIP (Session Initiation Protocol) IP phone DNs.

Option B is incorrect because a virtual SNR DN is not associated with multiple registered IP phones. It is associated with only one phone at a time, which is the device that answered the call.

Option C is incorrect because calls in progress cannot be pulled back from the phone that is associated with the virtual SNR DN. Once a call has been answered on a device, it cannot be transferred back to the virtual SNR DN.

Option E is incorrect because a call that arrives before a virtual SNR DN is associated with a registered phone can be answered from the phone after the association is made. The call will continue to ring on the other devices associated with the virtual SNR DN until it is answered on one of them.