Extension Mobility

The Cisco Extension Mobility feature, sometimes referred to as hoteling, allows a user to temporarily configure another IP telephone as his own. He therefore has to log into that IP telephone with a username and PIN. Once logged in, the phone has the users profile information, including his extension number (the reason for calling it ‘extension mobility’), dial permissions and other feature settings (e.g. call forwards).

As such it is an excellent function for people who are often travel between different company locations. They can use any fixed-line phone in the company as if it is their own telephone by just logging in. Extension Mobility is also very useful in situation where people don’t have a dedicated desk of their own. In a flex-office where people just enter and pick a desk, they can easily register on that desktop phone and use it as theirs. It is convenient since people can use their own features, but also it makes people reachable. The number of missed calls will be minimal.

There is one issue with the use of extension mobility. One really has to log into the telephone and that has to be done via the telephone keypad. If the username is easy and the pin code is short, this may not be the biggest problem. Still it means another combination of a username and pin that people have to remember. More challenging it is if organizations are using for example Active Directory where the username is shared over all applications. In that scenario it could be the case that an Extension Mobility user has to enter his email address using the telephone keypad.

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Wikipedia