Use in File Sharing Networks
Kademlia is used in file sharing networks. By making Kademlia keyword searches, one can find information in the file-sharing network so it can be downloaded. Since there is no central instance to store an index of existing files, this task is divided evenly among all clients: If a node wants to share a file, it processes the contents of the file, calculating from it a number (hash) that will identify this file within the file-sharing network. The hashes and the node IDs must be of the same length. It then searches for several nodes whose ID is close to the hash, and has his own IP address stored at those nodes. i.e. it publishes itself as a source for this file. A searching client will use Kademlia to search the network for the node whose ID has the smallest distance to the file hash, then will retrieve the sources list that is stored in that node.
Since a key can correspond to many values, e.g. many sources of the same file, every storing node may have different information. Then, the sources are requested from all k nodes close to the key.
The file hash is usually obtained from a specially formed Internet link found elsewhere, or included within an indexing file obtained from other sources.
Filename searches are implemented using keywords. The filename is divided into its constituent words. Each of these keywords is hashed and stored in the network, together with the corresponding filename and file hash. A search involves choosing one of the keywords, contacting the node with an ID closest to that keyword hash, and retrieving the list of filenames that contain the keyword. Since every filename in the list has its hash attached, the chosen file can then be obtained in the normal way.
Read more about this topic: Kademlia
Famous quotes containing the words file, sharing and/or networks:
“While waiting to get married, several forms of employment were acceptable. Teaching kindergarten was for those girls who stayed in school four years. The rest were secretaries, typists, file clerks, or receptionists in insurance firms or banks, preferably those owned or run by the family, but respectable enough if the boss was an upstanding Christian member of the community.”
—Barbara Howar (b. 1934)
“We fight our way through the massed and leveled collective safe taste of the Top 40, just looking for a little something we can call our own. But when we find it and jam the radio to hear it again it isn’t just ours—it is a link to thousands of others who are sharing it with us. As a matter of a single song this might mean very little; as culture, as a way of life, you can’t beat it.”
—Greil Marcus (b. 1945)
“The great networks are there to prove that ideas can be canned like spaghetti. If everything ends up by tasting like everything else, is that not the evidence that it has been properly cooked?”
—Frederic Raphael (b. 1931)