Typically and historically you think of caller ID information and you think of the numeric phone number or Directory Number (DN).  However, with the advancement of video and its common deployment as part of a full Unified Communications Manager enterprise rollout the SIP URI might become your preference.  In almost every organization that I’m familiar with the SIP URI for a user will match that user’s email address.  The two are of course not the same but the format is.  Likewise, as shared space device would also have a meaningful SIP URI describing it or the location it’s deployed in.  Either way the SIP URI is much more human readable and meaningful than remembering a phone number.  Because of this, some organizations may opt to use this information for the primary means of contact.  When receiving a call from a peer within the organization CUCM allows this SIP URI to be displayed instead of a DN when a user has a URI assigned.  Unlike VCS, which is videocentric at its core, CUCM is traditoinally voice centric and requires a DN with SIP URI as optional. In the event the user is not assigned an alpha numeric SIP URI the DN will still be displayed.

Lets look the default experience on a user’s 8865 IP phone when receiving a call from DN 1002 also identified by the SIP URI of EX60@technologyordie.com.  Here you can see the default behavior, the DN of 1002 is shown.

To give the alphanumeric SIP URI precedence toggle the “URI Dialing Display Preference” to “URI” under the “System->Service Parameters” menu.  The service to change is of course is the “Cisco Call Manager” service.   To make this change you will have to take a brief outage because the Call Manager service will have to be restarted as well.  This option field can be seen below:

After the brief service interruption the same call from the EX60 to our 8865 phone will now have its SIP URI displayed instead.

I hope you found this tutorial useful! Feel free to comment your questions or comments below.