A communications system includes a network coupled to various network
elements. The network elements include user systems that contain
protocol-aware applications that are aware of the protocol used to
establish streaming-type communications (e.g., audio, video, or
multimedia) or text-based communications over the network. The protocol
used for such communications may include the Session Initiation Protocol
(SIP), H.323, or other protocols. Each of the user systems includes a
rules engine that is capable of collecting information from a SIP message
and comparing the information to criteria or rules that have been entered
by a user. When a match occurs, one or more target applications or other
software routines are launched to perform predetermined tasks. The
launched applications or other software routines may include a web
browser, for example.