Two other hardware devices can control information security for an organization. A server, via hardware such as a proxy server (pretending to be something else) can control what the outside world sees of the network. Since the Internet is an open system, anyone can have access to any device that has connections and access. So one way that protection comes about is by putting up a "smoke screen" on the network. That would be the proxy server. It hides the real network, by showing a minimal connection to the Internet.
A router is a different device that can control access to the network. Like a firewall, it can have access lists that allow or prevent access into a network. They are like a firewall; however, they do more than just monitor access: They route IP packets to other networks. No other device on the network or the Internet does that.

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Both of these devices work to control access into the network, one direct (the router) and the other indirect (proxy server).
Image: AmitBhawani.com