Decentralized peer-to-peer session initiation protocol (P2PSIP) provides the same services as legacy SIPs such as IMS. However, in relatively open network, the requirement for route efficiency in a complex environment brings about undefined problems. To deploy a controllable P2PSIP network, perfect mechanisms have to be appended, especially in QoS, security, and management. Several proposals for QoS, network address translation (NAT), and interworking have been put forward. In this paper, we propose an integrated architecture for a P2PSIP system as well as a proactive intelligent routing scheme on the media plane used in system. Implementation and simulation show that our solution is suitable for operation and management.