Proxy servers provide a variety of essential functions for your LAN. First, a proxy server offers an effective and secure barrier between your internal network and the Internet. You can block various protocols and IP addresses from coming into your network; at the same time you can control the protocols your users use to access the Internet. Another benefit is that proxy servers allow you to share your Internet connection among several or even all users on the network. Finally, many proxy servers offer Web caching capabilities for storing previously visited Web sites and providing local access to users who re-visit the sites.

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