Mainline DHT
The idea of using a DHT for distributed tracking in BitTorrent was first implemented[1][2] in Azureus 2.3.0.0 (now known as Vuze) in May 2005, from which it gained significant popularity.If peers are found, the client downloads the file from multiple sources, similar to the standard BitTorrent protocol.[5] The SHA-1 hash of a torrent, the infohash, is synonymous with a Kademlia key, which is used for finding peers (values) in the overlay network.However, after the search is exhausted, the client then also inserts the peer contact information for itself onto the responding nodes with IDs closest to the infohash of the torrent.KRPC is a simple protocol that consists of nodes sending messages (queries, replies and errors) containing bencoded dictionaries over UDP.The transaction ID should be encoded as a short string of binary numbers, typically two octets are enough as they cover 2^16 outstanding queries.There are two benefits to this bucket implementation: Mainline DHT was first included in version 4.2.0 of the BitTorrent software (November 2005).