What is a proxy?
A proxy or proxy server or application level gateway is basically another computer which serves as a hub through which internet requests are processed. It acts as a gateway between your local network and internet (rest of the computers). By connecting through one of these servers, your computer sends your requests to the proxy server which then processes your request and returns the content that you are basically looking/requested for.
Why Use a Proxy?
If you want to surf the web anonymously then proxies can provide you with a means to hide your home IP address from the rest of the world. By connecting to the internet through proxies, the home IP address of your machine will not be shown but rather the IP of the proxy server will be shown. This can provide you with more privacy rather than connecting directly to the internet.
Proxies are used for a number of reasons such as to filter web content, to go around restrictions, to screen downloads and uploads and to provide anonymity when surfing the internet. Proxy servers also helping increasing performance and also improve security by filtering out some web content and malicious software, there by stopping unnecessary things entering the network and your computer.
How it works?
A proxy server works by intercepting connections between sender and receiver. All incoming data enters through one port and is forwarded to the rest of the network via another port.
A proxy server uses a network addressing scheme to present one organization-wide IP address to the Internet. The server takes all user requests to the Internet and returns responses to the appropriate users based on their requests. In addition to restricting access from outside, this mechanism can prevent inside users from reaching specific Internet resources.
A proxy server connects to, responds to, and receives traffic from the Internet, acting on behalf of the client computer.
Who uses them?
Generally Proxies are used mostly by networks in organizations and companies. People connecting to the Internet from home will not use a proxy server.
Proxy servers are used for both legal and illegal purposes. In the enterprise, a proxy server is used to facilitate security, administrative control or caching services, among other purposes. In a personal computing context, proxy servers are used to enable user privacy and anonymous surfing. Proxy servers can also be used for the opposite purpose: To monitor traffic and undermine user privacy.
An advantage of a proxy server is that its cache can serve all users. If one or more Internet sites are frequently requested, these are likely to be in the proxy's cache, which will improve user response time. A proxy can also log its interactions, which can be helpful for troubleshooting.
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