Personal Device Group supports the usage of two devices for one extension number in a OpenScape 4000 system. These are usually one desktop phone and one cordless phone (CMI).

The Personal Device Group concept is based on keyset functionality to allow multiple devices using the same number. Keyset configuration is also allowed for CMI and also a special Personal Device Group flag for the Keysets is introduced. The CMI device has the Personal Device Group number as prime line (Personal Device Group master) and the desktop phone has the Personal Device Group number as secondary line (Personal Device Group slave). The Prime Line of the Desktop Phone is not used.

Outgoing calls from the cordless or the desktop phone transmit always the same number (Personal Device Group number) to the destination.

Incoming calls are signaled on both devices and the user decides where to answer the call.

At the same time only one of the devices can initiate a call with Personal Device Group number. If the CMI is talking the desktop phone can not inintiate a call with Personal Device Group number.