What is 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 servers

You 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 header. 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.

Distorting Proxy
This type of proxy server identifies itself as a proxy server, but make an incorrect original IP address available through the http headers.

Anonymous Proxy
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.

Reverse proxy 
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.

In general, people think that proxy servers are those which are used to hide our IP adress in order to be anonymous on the internet. But anonimity is only a use of proxy servers. Read the full post to know what actaully the Proxy Server is?

Proxy server: Proxy server is the server system which acts as the intermediate between client and server systems. When a client want to connect to a server using proxy, client's system first connect to the proxy server, and proxy then connect client's request with the server system. In this way, client have an indirect connection with the target server system. But proxy do not have only the work of connecting client and server. It provide various service at the network level to improve the connectivity and and performance. It is mainly used for performance improvements and packet filtering

Every proxy server have some set of rules and the requests of the clients are evaluates based on those set of rules. If your college has blocked the facebook, twitter, youtube and some other websites, it means the proxy server of your college do not have some set of rules which block the requests to these websites. So it filters all the packets which request for the connection with these websites.

Proxy server also perform caching service so it can also serve some request without contacting with the original server. Thus it can improve the performance.

How it Provide anonymity:  As i have described above that Proxy server connects your system to the server indirectly. So the server knows only about the proxy not about you because you have no direct connection. Thus you are anonymous.

Advantages of Proxy servers: These are some advantages of the Proxy servers on the network.

• ·         Proxy servers provide anonymity on the internet due to indirect connection between users and servers.
• ·         It is used to scan the packets going outside and inside the networks. So it can used to determine the data leakage and data theft.
• ·         Proxy servers can also be used to block some websites on the network.
• ·         It can provide some features of Intrusion Detection system and Firewall
• ·         Firewall can also logs data usage of each user on the internet.

Types of Proxy servers:

• ·         Caching Proxy Server
• ·         WebProxy Server
• ·         Content Filtering Proxy Server
• ·         Anonymizing Proxy Server
• ·         Hostile Proxy Server
• ·         Transparent Proxy Server
• ·         Reverse Proxy Server

I will write about these type of proxy servers in detail incoming artiles. Stay tuned and subscribe for lates updates.