题目内容：
根据下列题干，回答题：Basically,a（ 71 ）is a standalone process or a set of integrated processes that runs on a router or server to control the flow of（ 72 ）application traffic（ 73 ）through it.Typically,firewalls are（ 74 ）on the entry point to a public network such as the Internet.They could be considered traffic cops.The firewall's（ 75 ）is to ensure that all communication between an organization's network and the Internet conform to the organization's security policies.
请选择（ 71 ）处最佳答案
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