Device Mobility Overview
The following are key characteristics and features of Device Mobility:
- Device Mobility can be used in multisite environments with centralized call processing within a single CUCM cluster.
- Device Mobility allows users to roam between sites with their Cisco IP Phones, which typically are Cisco IP Communicator or Cisco Unified Wireless Phones.
- IP Phones are assigned with a location-specific IP address by DHCP scopes specific to each location.
- CUCM determines the physical location of the IP Phone based on the IP address used by the IP Phone.
- Based on the physical location of the IP Phone, the appropriate device configuration is applied.
Device Mobility allows users to roam between sites with their IP Phones. Typically, these are Cisco Unified Wireless IP Phones or Cisco IP Communicator Phones.
When the device is added to the network of roaming sites, it is first assigned with an IP address. Because the IP networks are different in each site, CUCM can determine the physical location of the IP Phone based on its IP address.
Based on the physical location of the IP Phone, CUCM reconfigures the IP Phone with site-specific settings.
Dynamic Device Mobility Phone Configuration Parameters
Two types of phone configuration parameters can be dynamically assigned by Device Mobility: Roaming-Sensitive Settings and Device Mobility-Related Settings.
Device Mobility can reconfigure site-specific phone configuration parameters based on the phone's physical location. Device Mobility does not modify any user-specific phone parameters or any IP Phone button settings such as directory numbers or phone services.
The phone configuration parameters that can be dynamically applied to the device configuration are grouped in two categories:
- Roaming-Sensitive Settings
- Date/Time Group
- Connection Monitor Duration
- Network Locale
- SRST Reference
- Media Resource Group List (MRGL)
- Physical Location
- Device Mobility Group
- Device Mobility-Related Settings
- Device Mobility Calling Search Space
- AAR Calling Search Space
- AAR Group
Roaming-sensitive settings are settings that do not have an impact on call routing. Device Mobility-related settings, on the other hand, have a direct impact on call routing, because they modify the device CSS, AAR group, and AAR CSS. Depending on the implementation of Device Mobility, roaming-sensitive settings only, or both roaming-sensitive settings and Device Mobility-related settings, can be applied to a roaming phone.
Device Mobility Dynamic Configuration by Location-Dependent Device Pools
Figure 11-2 illustrates the location-dependent parameters such as roaming-sensitive settings and Device Mobility-related settings that are configured at device pools. Based on the IP subnet that is used by the phone associated with a device pool, CUCM can choose the appropriate device pool and apply the location-dependent parameters. With the introduction of Device Mobility, CUCM is aware of the physical location of a device based on its IP address within its subnet and applies the appropriate location-specific configuration by selecting the corresponding device pool.
Figure 11-2 Device Mobility with a Dynamic Configuration by Location-Dependent Device Pools