Monday, June 18, 2012 0 comments
What is a Proxy Server?
It is a server that sits between a client application, such as a Web browser, and a real server for which client requested. Proxy server is a computer that offers a computer network service to allow clients to make indirect network connections to other network services. It intercepts all requests from client to the real server to see if it can fulfill the requests itself. If not, it forwards the request to the real server.In some cases, the proxy may alter the client's request or the server's response for various purposes.
Proxy servers have two main purposes:
Improve Performance: Proxy servers can improve performance for users. This is because it saves the results of all requests for a certain amount of time. Next time if same request comes, it serves from the saved pages rather than the real server.
Filter Requests: Proxy servers can also be used to filter requests. FOr Ex: a company might use a proxy server to prevent its employees from accessing a specific set of Web sites.
Types of proxy serversYou may see different types of proxy servers:
Transparent Proxy or Caching
This type of proxy server identifies itself as a proxy server and also makes the original IP address available through the http headers. These are used for their ability to cache websites and do not effectively provide any anonymity to those who use them. However, the use of a transparent proxy will get you around simple IP bans. They are transparent in the terms that your IP address is exposed, not transparent in the terms that you do not know that you are using it.
This type of proxy server identifies itself as a proxy server, but make an incorrect original IP address available through the http headers.
This type of proxy server identifies itself as a proxy server, but does not make the original IP address available. This type of proxy server is detectable, but provides reasonable anonymity for most users.
High Anonymity Proxy
This type of proxy server does not identify itself as a proxy server and does not make available the original IP address.
A reverse proxy is another common form of a proxy server and is generally used to pass requests from the Internet, through a firewall to isolated, private networks. It is used to prevent Internet clients from having direct, unmonitored access to sensitive data residing on content servers on an isolated network, or intranet. If caching is enabled, a reverse proxy can also lessen network traffic by serving cached information rather than passing all requests to actual content servers.