Many free/freeware programs and operating systems, such as the various Linux distributions offer a torrent download option for users seeking the aforementioned benefits.
The torrent protocol addresses this by decentralizing the distribution, leveraging the ability of people to network "peer-to-peer", among themselves.
In this way, the burden on the network is spread among the downloaders, rather than concentrating at a central distribution hub or cluster.
In order to learn the internet locations of peers who may be sharing pieces, the client connects to the trackers named in the torrent file, and/or achieves a similar result through the use of distributed hash tables.
Then the client connects directly to the peers in order to request pieces and otherwise participate in a swarm.
A torrent is uniquely identified by an infohash, a SHA-1 hash calculated over the contents of the info dictionary in bencode form.
The "btmh" magnet link would contain the full 32-byte hash, while communication with trackers and on the DHT uses the 20-byte truncated version to fit into the old message structure.
However, as a torrent would have different infohashes in v1 and v2 networks, two swarms would form, requiring special handling by the client to merge the two.
[3] A core feature of the new format is its application of merkle trees, allowing for 16KiB blocks of a piece to be individually verified and re-downloaded.
The file size is not reduced (assuming piece size stays the same; v2's tree structure allows larger pieces with fewer ill effects), but the info dictionary required for magnet links are (only in v2-only torrents).
While they may require minor revisions, they are largely considered to be complete, only awaiting the blessing of Bram Cohen in order to be elevated to the status of Final/Active Process.
BEP-0005[5] extends BitTorrent to support distributed hash tables, specifically Mainline DHT.
Alternatively, the key could be set to a known good node such as one operated by the person generating the torrent."
A new key, announce-list, is placed in the top-most dictionary (i.e., with announce and info) BEP-0019[7] is one of two extensions allowing HTTP seeds to be used in BitTorrent.
The client uses the links to assemble ordinary HTTP URLs – no server-side support is required.
Web seeds allow smart selection and simultaneous use of mirror sites, P2P or HTTP(S), by the client.
Decentralized methods like DHT, PeX, LSD are disabled to maintain the centralized control.