Multilevel Precedence and Preemption in the Session Initiation Protocol
Cisco Systems
This document proposes considerations and requirements for the extension of the Session Initiation Protocol (SIP) [1] to support Multi-Level Precedence and Preemption (MLPP) functionality originally set forth in [2&3]. This document will be limited in scope to the requirements of the SIP Protocol; MLPP within the IETF, utilizing other IETF Protocols, is left to other documents, therefore is considered out of scope here - although there is a general explanation of how MLPP functions currently within private circuit switched networks to give the necessary operational background for these requirements.