Abstract:The network structure of large enterprises is complex. It requires cooperation between every department. Building a security policy system of multi-node cooperative mechanism can efficiently solve the problem onthe cooperative security management for large enterprises network. Based on the above background, this paper uses C/S structure, introduces the principle of ant colony and the algorithm of intrusion detection, to carry out a research on the coordination mechanism and security system of multi-node based on IPv6. The designed system in this paper is tested. The result shows it can handle the security problem of the large enterprises network well. It also implements the effective collaboration between large enterprises networks, and solves the problem on the cooperative security management of large enterprises network.