Question

Provide a diagram and description of how a proxy firewall operates. Identify the key features of the proxy-based firewall and what it is designed to protect clients from?

Answer 1

A Proxy is a central machine on the network that allows other machines in that network to use a shared Internet connection. Proxy servers are intermediate servers which accept requests from clients and forward them to other proxy servers, a source server, or service the request from their own cache. The proxy is also called 'server' or 'gateway'. Proxy allows users on a network to browse the Web, send files over FTP, and work with E-mail and other Internet services.

A Firewall Proxy provides Internet access to other computers on the network but is mostly deployed to provide safety or security. It controls the information going in and out the network. Firewalls are often used to keep the network safe and free of intruders and viruses. Firewall proxy servers filter, cache, log, and control requests coming from a client. A firewall proxy is one that is used for restricting connections from a proxy to the outside world or to the source server inside of the LAN. This is different from a conventional firewall, in that a conventional firewall restricts connections coming from the outside world.

How the Proxy Works

Simply put, proxy are gateway applications used to route Internet and web access from within a firewall. Proxy servers work by opening a socket on the server and allowing the connection to pass through. There is often only one computer in a company with direct Internet connection. Other computers have access to the Internet using that computer as gateway.

A proxy basically does the following:

1. Receives a request from a client inside the firewall
2. Sends this request to the remote server outside of the firewall
3. Reads the response
4. Sends it back to the client

aanse Proxy Firewall Internet

Usually, the same proxy is used by all of the clients on the network. This enables the proxy to efficiently cache documents that are requested by several clients.