Processing of multimedia calls in a packet-based network builds on existing call model processing by maintaining the use of the basic call state models to control the overall two-party call and the use of connection views to associate multiple two-party calls and provide access to advanced supplementary services. Through the use of a multimedia view processor, the system separates multimedia connection handling from call handling. The basic call models are extended to support new messages and enhanced messages for creating, modifying, and deleting multimedia view objects and communicating modifications to the media streams between call state model processors and protocol specific processors.