The network firewall controls the data flow between devices or systems by setting different security rules.In practical applications,it is mainly used to analyze the TCP/IP protocol suite connected to the Internet.The premise of using a firewall in the network is to ensure the connectivity of the network.It restricts and filters the information that is sensitive to management and insecure through rule setting and protocol analysis to prevent unauthorized access.Due to the differences between industrial control and commercial networks,there are many problems with conventional network security setting rules applied to control networks.
网络防火墙通过设置不同的安全规则来控制设备或系统之间的数据流，在实际应用中主要用于分析与互联网连接的TCP/IP协议簇。防火墙在网络中使用的前提是必须保证网络的连通性，其通过规则设置和协议分析，来限制和过滤那些对管理比较敏感、不安全的信息，防止未经授权的访问。由于工业控制与商用网络的差异，常规的网络安全设置规则用在控制网络上就会存在很多问题。
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