Webcaché is a feature of some P2P in the ed2k network, such as Lphant and some eMule mods, and makes use of the proxy-cache. It is a machine used by companies that offer internet, ISPs; and which are generally used to save data traffic to ISPs in Internet browsing. These machines "keep" in their memory what has just passed through it in the transit from one PC to another.
Users who use the WebCache option in these programs upload a piece of the file they share. In this way, another user is allowed to ask the initial source user for that piece of file, actually asking the same piece of file to the proxy-cache, which has it in his memory; which is much faster than the uploader. User 2 then requests the proxy cache and lowers the file at a high speed without spending the bandwidth of the uploader. These proxy machines have a gigantic bandwidth, more than any current connection between users, allowing you to take advantage of the connection speed, as long as they do not collapse.
Currently the webcache option has fallen into disuse because ISPs have stopped using proxy-cache. Because of this, the most important eMule mods have made this feature one of their options.
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