What are the Different Types of Proxies According to Function?
There are different types of proxy servers based on their function and the objective they are seeking to fulfill.
Web Poxies
This is the most common proxy application. Caching web proxies provide copies of frequently downloaded or requested Internet resources thereby making access to them quick and reliable. When a client requests for data from a remote server, the proxy server, which acts as intermediary, normally goes through its cache to see if what you are asking for is available. If it is, then it sends out the information you are asking for immediately. If, however, it is not, then it fetches it from the remote server, saves a copy, then sends the file you requested to you.
Some web proxies implement censorware applications and filter the content of web pages served to 'block out' distasteful web content. Others reformat the web pages to allow them to be accommodated by specific networks as in the case of PDA's and cell phones.
A special kind of web proxy is known as the 'CGI Proxy.' These are websites that protect users from spammers or entities that may threaten to violate their privacy by allowing these users to surf the net and other remote servers through them. Since the IP address serves as a user's digital ID online, this proxy hides the user's IP address thereby allowing the user to surf anonymously and go shopping online anonymously.
- Open Proxies
These are proxy servers that accept connections from any IP address and which connect to any Internet resource. These proxies are of the HTTP and SOCKS type. The HTTP Proxy is the most widely known and widely used proxy. The SOCKS proxy is able to work with any type of information on the Internet. To be able to use them, both HTTP and SOCKS proxies require the user to configure his browser's proxy. Both proxies also have the unique advantage of compatibility with almost all web pages.
The use of open proxies is open to abuse, however, and is not recommended. Because they connect to almost all types of web pages, in some cases, they connect to computers that are compromised or operated by malicious individuals. Some known users of open proxies are into credit card fraud, pay-per-click fraud, and illegal hacking. It is therefore not recommended that users subscribe to open proxies.
- Intercepting Proxy
This type of proxy combines the characteristics of a proxy server with Network Address Translation or NAT. Intercepting proxies are often used in business to prevent avoidance of acceptable use policy. They are also used by Internet Service Providers to ease up on the bandwidth demand through the provision of a shared cache among customers.
The intercepting proxy is often mistakenly called the transparent proxy. This is false. The transparent proxy, unlike the intercepting proxy, does not alter the request or response other than whatever is necessary for proxy authentication and identification.
- Split Proxy
A split proxy refers to a pair of proxy servers installed across two computers. Part of the same program, split proxies are able to communicate with one another and are useful in compressing data over a slow link such as a wireless or mobile data service.
- Reverse Proxy
This type of proxy is installed in one of the neighboring sites of one or more web servers. All traffic coming from the Internet to any one of the web servers will have to go through this proxy server. Installing the reverse proxy is beneficial because (1) it provides another layer of defense, (2) it offers SSL Acceleration/Encryption, (3) it contributes to load balancing, and (4) it allows optimization and compression of content thereby speeding up load time.
- Circumventor
This refers to a web-based page that allows users to view 'blocked' sites/pages by 'circumventing' these blocked sites through websites that are unblocked. Using circumventors is generally safe unless the sites are run by unscrupulous third parties.