Abstract: With the popularization and application of the IP multimedia subsystem (IMS) administrative switching network of the State Grid Corporation of China, the number of IP multimedia subsystem has gradually increased. On the basis of the IMS administrative switching network system architecture and core network element capabilities, a platform system with open service capabilities that can shield the underlying professional specific protocols is designed, and the open interface is provided to avoid the conflict between multiple services through the multi-point service triggering model, and the architecture design of the IMS service capability open platform and the third-party user registration and call processing process are given.The system solves the problems of mutual independence, difficultinterconnection and interconnection, and insufficient expansion capabilities of users and terminals between traditional service platforms, shortens the generation cycle of new services, and provides personalized services according to the needs of individual users, which is more conducive to the sustainable development of the network.

    Key words: administrative switching network; IP multimedia subsystem; electric power business; architecture design; API interface; trigger model