X-GATE is a client-server based protection system which can protect the critical data of an enterprise from being leaked via network transfer. It can monitor every computer of an enterprise according to the permission which the administrator has given to the user, where it controls the internet activity which the users can accomplish, such as website browsing and the control of web mail, web HD, FTP file transfer and instant messengers. With the management application, the IT staff can design a suitable permission for each user according to its job position. Therefore, the network usage of the users will be monitored closely, such as the access of internet, message transfer, file transfer, logs, traffic flow statistics, and so on.