Patent ID: 8218533

Claim:
A telephony system comprising a plurality of telephones, each telephone supporting a SIP protocol and voice over Internet Protocol telephony; a SIP proxy server receiving SIP REGISTER messages from the plurality of telephones; a back end server communicating with the SIP proxy server; wherein each telephone comprises a telephone user interface comprising a plurality of buttons, the buttons including a program button, a programmable mapped button, digit buttons, and one or more function buttons associated with telephone functions; wherein each telephone is constructed and arranged wherein the program button permits a user to program the programmable mapped button to invoke an arbitrary sequence of button strokes selected by the user, the arbitrary sequence of button strokes including at least one function button and at least one digit button or extension button, wherein, after programming the mapped button, the sequence of button strokes is invoked by pressing the mapped button; and wherein after programming the mapped button a SIP message containing information as to the sequence is sent from the telephone to the proxy server and the sequence of button strokes is stored in a memory associated with the back end server.