Identifying Individual Telephone Instruments in SIP
Nortel
When requesting and reporting dialog status in SIP, users often want to know the status of a particular telephone instrument, rather than the status of an Address of Record (AOR). The architecture of SIP makes it difficult to obtain the status of a telephone instrument in a way that is convenient for use in common situations, in particular, in an organization's PBX. This document describes two methods for identifying which telephone instrument is making each registration request that is convenient to deploy in PBXs. This information can be used to obtain the status of individual telephone instruments.