Proxy Servers, all You need to know. Hello everyone and Welcome back to another blog!!! Before we dig more into the details about Proxy Server and types of proxy server it is very important to understand what a proxy server is and what are the functions of a proxy server. A Proxy server is a computer acts as a gateway (application-level-gateway). It is a dedicated computer/server that acts as an intermediate between a client and a server from which the client is requesting service. Proxy servers offer better performance and security by caching requests from the client. There are different types of proxy servers depending on the type of request they handle, they are: Tunnelling Proxy: A proxy server that handles unmodified request from clients. Forward Proxy: A Proxy server (Web) which is available on internet and can be accessed literally by anybody is otherwise known open proxy. It is estimated the number of open proxy server is in thousands. It provides anonymity while browsing the internet. However sometimes users are tricked and the proxy reveals user’s information. Reverse Proxy: A Proxy server that forward requests to one or more server, but not directly accessible or visible by clients. The application of reverse proxy includes : 1. Encryption/ SSL acceleration 2. Load Balancing 3. Server static content 4. Compression 5. Spoon-feeding 6. Security 7. Extranet publishing Though proxy server have various usage some are legal and some are illegal, lot of countries constantly monitor and ban proxies as users can access all banned content using a proxy or vpn. Some of the very common usages are: i. Content Control: It provides administrative control over the content relayed in one or both direction. It provides ability to System Administrators to enforce Acceptable Usage Policy of the organisation, by blocking unwanted websites (Porn sites, Gambling sites, Social networking websites, etc.). It also provides a better insight of content usage trend analysis. ii. Bypass Filter and Censorship: This is the most common technology to by-pass government censorship. For using a service like (torrent sites or any other blocked content) this is mostly used. iii. Improving Performance: It cache users requests and thus the request does not have to query internet naming server/DNS every time. It is also very helpful while troubleshooting DNS or Network related issues. iv. Translation: This proxy server sits close to the web server and all global requests lands on the proxy server which helps localizing the webserver by forwarding the request to the webserver and response to the client. v. Accessing services anonymously: There are lot of open proxy servers which provides anonymity, some of them provide free service and some are paid. But before trusting the proxy server and trying it out be very careful as the information passed through the proxy server like your credentials or personal photos can be stolen and miss used. vi. Security: Proxy server help keeping intranet or internal network secure, as it handles both in and out traffic of the organisation and anonymizing the request from internal users.