Cisco O-8637-01 - Manual (Page 5)

19-5
Cisco CallManager Features and Services Guide
O-8637-01
Chapter 19 Cisco CallManager Device Mobility
Introducing Device Mobility
Device Pools
After the device mobility groups and physical locations are identified, you can
associate them with device pools. Each device pool contains the set of parameters
that apply to devices, and adding the device mobility group and physical location
ties the device pool to those entities.
Device Mobility Information
In the final step in designing a device mobility structure, you associate subnets
with the device pools that contain the device mobility group and physical location
information. When a phone registers and obtains an IP address, the system
compares the address to device mobility subnets that are associated with one or
more device pools. The matching subnet becomes the device home subnet for the
purpose of device mobility.
Phone Configuration
After the device mobility structure is in place, you can turn device mobility on for
IP phones that are provisioned to be mobile.
Device Mobility Process
This section describes how Cisco CallManager manages phone registration and
assignment of parameters for device mobility.
Following initialization, the Device Mobility feature operates according to the
following process:
1. A phone device record gets created for an IP phone that is provisioned to be
mobile, and the phone gets assigned to a device pool. The phone registers
with Cisco CallManager, and an IP address gets assigned as part of the
registration process.
2. Cisco CallManager compares the IP address of the device to the subnets that
are configured for device mobility in the Device Mobility Info window. The
best match uses the largest number of bits in the IP subnet mask (longest
match rule). For example, the IP address 9.9.8.2 matches the subnet
9.9.8.0/24 rather than the subnet 9.9.0.0/16.