The proxy software often good support for Internet services and popular such as: FTP, Telnet, HTTP but for the less popular and new services, it is difficult to find. There is always a gap between the introduction of a service and support proxy ready for it, depending on the level of services designed to support Proxy This makes it difficult for a website to offer a new service immediately. Before an appropriate proxy software, a system that needs the new services will be placed outside the firewall, creating a security hole.
You may need a proxy server for each protocol, because the proxy must understand it to determine what is allowed and not allowed. The installation and configuration proxy will take more efforts. Usually easy to configure proxy server will lose flexibility, because they will make available to the assumption about how to operate, but this is often not suitable for a site.
The proxy service does not protect you from all the weak points of the protocol: as a security solution, proxy based on the ability to identify those activities in a safe protocol. Not all protocols provide the easy way to do HTTP is designed to operate with a proxy server, but it is also designed for easy expansion, and it achieves this aim by transmitting data be executed.
Alive Proxies (Last checked in past 24 hours):