Bittorrent dht what is it

Learn more. Ask Question. Asked 8 years, 6 months ago. Active 4 years, 11 months ago. Viewed 18k times. Note: simple explanations are best.

Improve this question. Community Bot 1. Steve V. Add a comment. Active Oldest Votes. Summary How can a new client join a swarm without either a tracker or the knowledge of at least one member of the swarm to exchange peers with? You can't. It is impossible.

References Bittorrent DHT is implemented via a protocol known as Kademlia , which is a special case of theoretical concept of a Distributed hash table. Exposition With the Kademlia protocol, when you join the network, you go through a bootstrapping procedure, which absolutely requires that you know, in advance , the IP address and port of at least one node already participating in the DHT network.

Improve this answer. The way you describe DHT sounds the same as peer exchange. The thing that's Distributed about DHT is that the actual data payload -- meaning, the list of IPs and ports where files can be downloaded -- is distributed. In a peer exchange, the entire list is stored on one computer, usually the tracker, and downloaded not dissimilarly to a file download. I could mention that in my answer, but this entire question and the answers is only about initial discovery or joining of the DHT network, not about what happens after you join.

Hitting all the bootstrap nodes would stop new users from bootstrapping, but not necessarily existing users that go offline and then come back. I have the impression that several of the clients remember their active node set and use them to reconnect, rather than bootstrapping every time. With projects like masscan github. However, DHT can use a random port. You would still probably find clients on the default port ?

Short answer: It gets it from the. Spiff Spiff This is good, explanatory information. I think your answer explains what current BitTorrent clients do to handle the theoretical limitations and problems that are identified in my answer. Hopefully both of our answers are upvoted, as they explain different aspects of the answer. Is that why the "merge new torrent file with downloading torrent" in many clients makes a dead torrent come alive? It appears that no BitTorrent client actually include the nodes information.

Have tested Transmission, Vuze, Deluge, Mainline, and others. It asks for it. The links is dead — zella. Sign up or log in Sign up using Google. Sign up using Facebook. Sign up using Email and Password.

Post as a guest Name. Closeness is measured by comparing Node ID's routing tables, the closer the Node, the more detailed, resulting in optimal.

Besides not being secure, its logic was flawed. If the handshake is successful the above will continue. Stack Overflow for Teams — Collaborate and share knowledge with a private group. Create a free Team What is Teams? Collectives on Stack Overflow. Learn more. How does DHT in torrents work?

Ask Question. Asked 12 years, 2 months ago. Active 2 years, 9 months ago. Viewed k times. Improve this question. Christopher Tarquini Christopher Tarquini Add a comment. Active Oldest Votes. Improve this answer. If you only specify opts. For mutable content, the hash will be the hash of the public key, opts.

These options are available:. Note that bittorrent bep44 uses ed You can use the edsupercop package to generate the appropriate signatures, bittorrent-dht-store-keypair , bittorrent-dht-sodium or for a more convenient version.

To make a mutable update, you will need to create an elliptic key and pack values precisely according to the specification, like so:. In either mutable or immutable forms, callback error, hash, n fires with an error if no nodes were able to store the value. Note that you should call. Read a data record created with. Given hash , a hex string or buffer, lookup data content from the DHT, sending the result in callback err, res. Emitted when the DHT is fully bootstrapped i.

Note that it is okay to do lookups before the 'ready' event fires. It is assumed that you will manually populate the routing table with dht. Emitted when a potential peer is found. Emitted in response to a lookup infoHash call. This is purely informational. Git github. This module is used by WebTorrent.