CUCM Extension Mobility

 

Extension Mobility Configuration Elements

Configuration Element Name	Configuration Element Function
Phone	Stores the configuration of physical phones. Configuration parameters include device-specific phone parameters (such as device CSS, location, or MRGL), user-specific phone parameters (such as user MOH audio source, DND, or softkey template), and (user-specific) button configuration (such as lines or speed dials).
End User	The end user is associated with one or more device profiles. The User ID and the PIN are used to log in to a phone with Extension Mobility.
Device profile	Stores user-specific phone configuration in logical profiles. Configuration parameters include user-specific phone and button parameters (such as lines and speed dials). The parameters of the device profile are applied to a physical phone after a user logs in to the phone using Extension Mobility.
Phone service	Extension Mobility is implemented as a phone service. Hardware phones and device profiles have to be subscribed to the service.
Default device profile	Stores the default device configuration parameters that should be applied when the phone model of a user’s device profile is different from the phone model of the phone where the user logs in.

Relationship Between Extension Mobility Configuration Elements

EM Operation

1. The user presses the Services button on the phone and chooses the Extension Mobility
service from the list of phone services available at the phone.

2. The Extension Mobility service requires the user to log in using his or her user ID and
PIN. The user enters the required data on the phone by pressing each phone button as
many times as needed to select the alphanumeric characters for his or her user ID
and PIN.

3. If the entered user ID and PIN are correct, Extension Mobility chooses the device
profile that is associated with the user.

NOTE If a user is associated with more than one device profile, all associated profiles
are displayed, and the user has to choose the desired profile, as illustrated for User2 in
Figure 12-3. Assigning multiple profiles to a user means that the user is provided with a
separate device profile for each site. Doing this is common when the traditional approach
is used to implement Calling Search Spaces (CSS). Extension Mobility updates only the
line configuration, including the line CSS, but not the device CSS. To allow the choice
of a local gateway for outbound PSTN calls, a different line CSS has to be applied for
each site. In such a scenario, the user chooses a site-specific device profile that differs
from the device profile that is used at other sites in its line CSS. The line CSS of such
site-specific profiles gives access to route patterns that route PSTN calls to the appropri-
ate local gateway to minimize toll charges. Extension Mobility also works well if the
more modern approach of gateway selection of PSTN at the device (phone) level and
blocking the CSS at the line level is implemented.

4. CUCM updates the phone configuration with the settings of the chosen device profile.
User-specific device-level parameters, lines, and other phone buttons are updated with
user-specific settings.

5. The IP Phone is reset and loads the updated configuration.

 

Extension Mobility Solution to Phone Model Differences
After successful authentication, if the phone model of the device profile does not match the
phone model of the actually used phone, the following happens:

1. Device-dependent parameters such as the phone button template and softkey template
from the default device profile are applied to the phone.

NOTE If the phone button template that is configured in the user's device profile
matches the number of buttons on the login device, the system uses the phone button
template from the user's device profile. Otherwise, the system uses the phone's default
device profile for phone button configuration.

2. The system copies all device-independent configuration settings, such as user hold
audio source, user locale, speed dials, and line configuration, from the device profile to
the login device. Exceptions are the parameters specified under line settings for this
device.

3. The applicable device-dependent parameters of the user's device profile are applied.
These parameters include buttons (such as line and feature buttons) based on the phone
button template that has been applied from the default device profile.

4. If supported on the login device, phone service subscriptions from the user's device
profile are applied to the phone.

5. If the user's device profile does not have phone services configured, the system uses
the phone services that are configured in the default device profile of the login device.

 

EM Configuration

Step 1 Activate the Cisco Extension Mobility service in CUCM for the cluster.

Step 2 Set Cisco Extension Mobility service parameters.

Step 3 Add the Cisco Extension Mobility phone service.

Step 4 Create default device profiles for all phone models used.

Step 5 Create device profiles, and subscribe them to the Cisco Extension Mobility phone service.

Step 6 Create end users, and associate them with device profiles.

Step 7 Enable Extension Mobility for phones, and subscribe the phones to the Cisco Extension Mobility service.

Reference:

CIPT2 v6.0 Chap12 Implementing Extension Mobility