Building value-added services using mobile agents in SIP-based Internet telephony.

摘要

Internet Telephony is attracting a great deal of attention in modern society. IETF SIP is a standard for Internet telephony, but SIP service architecture has some shortcomings, for instance, it does not support service mobility.;This thesis proposes a novel mobile agent based service architecture for Internet Telephony. The architecture relies on the use of two mobile agents for each subscriber: one agent contains originating services and the other contains terminating services. These two mobile agents act as capsules and carry the services to which the user has subscribed. The architecture brings the advantage associated with mobile agents. This includes network traffic reduction and flexibility in service provisioning. We start the thesis by introducing value-added services. The MA based architecture for IP telephony is then introduced. Conceptual model, implementation model, and service scenarios are all described in this architecture. Special attention is paid to service mobility. SIP is used as concrete example throughout the thesis and "Grasshopper" as basis for the implementation architecture.