The forth chapter expounded the network security program based on Waterwall, which is an potent supplementaty to Firewall, virtual special-purpose net, the Intrusion Detection system etc.

• 在第五章中通过对四川省威远县酒厂的信息系统的改造,介绍了适合于中小型企业的网络安全产品----UTM(统一威胁管理)。