Abstract: Network security auditing is an important task of network management,and it is also an important way to ensure network security and stability.Common network security audit system is complex and high cost.In view of this,we proposed a network security audit system based on redirection of DNS.The method by modifying the DNS configuration in gateway can monitor the data without changing the structure of the network or the configuration of clients.Experimental results show that it is simple,low cost and helpful for administrators to improve their capability of network ma-nagement.

Key words: Security audit,Redirection,TransProxy