Raised by Wolves S01E02 Raised by Wolves S01E06 Idhun s01e01 The Babysitter Killer Queen 2020 F1 motogp Solitary 2020 The 2nd 2020 Power Book II Ghost S01E04 the boys Secret Society of Second Born Royals 2020 Avengers Endgame 2019 Mulan 2020 raised by wolves Project Power 2020 Greenland 2020 Lovecraft country Raised by Wolves S01E01 the 100 rq.mp4 The Comey Rule S01E01 Rogue 2020 The Boys S02E06 Greyhound 2020 The Boys S02E05 The Boys S02E01 Attack of the Unknown 2020 Last Week Tonight Knives Out 2019 Nomadland 2020 Enola Holmes 2020 Antebellum 2020 The Devil All the Time 2020 Tenet 2020 After We Collided 2020 xxx Ratched S01E01 Raised by Wolves S01E08 etrg Fargo S04E02 Unhinged 2020 Lost Girls and Love Hotels 2020 The New Mutants 2020 The War with Grandpa 2020 tenet ufc Raised by Wolves S01E07 etmovies formula 1 Ava 2020 90 Day Fiance Happily Ever After S05E16 ettv Alone 2020 fargo Fargo S04E01 Peninsula 2020 wwe Raised by Wolves S01E09 ddr Power Book II Ghost S01E03 ethd Hard Kill 2020 yts Utopia S01E01 evo Bill and Ted Face the Music 2020 Lovecraft Country S01E07 Joker 2019 Money Plane 2020 The Owners 2020 The Boys S01E01 Hindi Last Week Tonight with John Oliver S07E24 
Warning! Use a VPN When Downloading Torrents!
Your IP Address is Location United States
Your Internet Provider can see when you download torrents! Hide your IP Address with a VPN
ETTV warns: You should use VPN to hide your torrenting. HIDE ME NOW
P2P News > Libtorrent Adds Support for BitTorrent v2, a Potential Game-Changer

You are in:  Forums / P2P News / Libtorrent Adds Support for BitTorrent v2, a Potential Game-Changer
gerald99DonatedPost has 1 Like and 0 Dislike | Posted at 2020-09-14 14:40:46(2 wks ago)

Posts: 730

September 12, 2020 by Ernesto Van der Sar

Libtorrent has just released version 2.0, which is a potential game-changer. The BitTorrent library, which is used by popular clients including uTorrent Web, Deluge, and qBittorrent, adds support for the new BitTorrent v2 protocol specification. This opens the door to various new features and introduces a new torrent format, which creates a separate swarm.

Millions of people use BitTorrent every day but only a few know all the ins-and-outs of how it works.

Meanwhile, an even smaller group is actively involved in shaping the future of the file-sharing protocol.

BitTorrent was first made public by inventor Bram Cohen nearly two decades ago. While it was swiftly embraced by the masses, the protocol itself was far from perfect. Over the years many new features were added, including DHT, UDP trackers, peer-exchange, and support for streaming.

As developer of one of the leading BitTorrent libraries, Libtorrent, Arvid Norberg has been closely involved in the protocol’s development. It’s his code that makes a wide variety of torrent clients function properly. This includes uTorrent Web, Deluge, and qBittorrent.

LibTorrent 2.0 and BitTorrent v2
This week, Norberg announced the latest release of Libtorrent; version 2.0. This new version comes with many changes that eventually will make their way to torrent clients. The most crucial one is the implementation of the BitTorrent v2 protocol specification.

BitTorrent v2 is an improved version of the early BitTorrent standards and includes several technical changes. It was first proposed by Bram Cohen in 2008 and updated and improved along the way. Since most changes take place under the hood, the public at large won’t immediately recognize them, except for one.

Tech-savvy readers can get the complete lowdown from the Libtorrent site but for the sake of simplicity, we will focus on how the changes will affect users.

V2 Torrents and Separate Swarms
BitTorrent v2 changes the way torrents are ‘compiled’ and the newer version is not backward compatible. Older torrents have a SHA-1 hash and the new versions use SHA-256 hashing. This means that going forward, there will be different torrent versions.

These different (v1 and v2) torrents will also create separate torrent swarms. People who download a v1 torrent can’t share anything with people who download a v2 torrent and vice versa. While that sounds like a step back, the reality isn’t that bad.

There is an option to create so-called “hybrid” torrents that can connect to both swarms. These are basically two torrents in one. As a result, all torrents will have the same number of people sharing.

“A v2-enabled client would still be able talk to all peers, and peer-exchange would still work across v1 and v2-enabled peers. The main impact, I think, is that a v2-enabled peer would announce twice for a hybrid torrent, once for each info-hash. Both to trackers and the DHT,” Norberg tells us

For now, it makes sense that publishers, including torrent sites, are best off using hybrid torrents. After all, torrents that only use the v2 specification will have access to a limited number of peers. Norberg agrees.

“I think it would make sense for publishers to generate hybrid torrents. At least experiment with it to ensure it works well. v2-only torrents would only make sense for closed ecosystems right now, where the publisher also controls all clients.”

Important Changes Under The Hood
While new torrents are the most visible change, for outsiders it’s merely a byproduct of important changes under the hood. For example, the switch from SHA-1 to SHA-256 hashing will prevent a possible hash collision, which can be used for attacks and exploits.

Norberg tells is that the risk of these attacks is mostly theoretical, but this may change over time. So changing to SHA-256 is certainly wise. An even more exciting change, according to the developer, is the use of ‘per-file merkle hash trees’ for the piece hashes.

In simple terms, this means that all files in a torrent will have their own unique identifier (hash). So, a collection of 100 photos will have a unique hash for each photo. This comes with several advantages.

For example, it will allow torrent clients to quickly check if they are receiving the right file. This prevents pollution attacks that can be used by outsiders to slow down torrent transfers.

“With the v2 hash trees, corrupt data will be detected immediately and the peer responsible for it can be disconnected. Currently, there’s more complex heuristic involved in attributing corrupt data to a peer, which means a malicious peer can do slightly more damage before being disconnected,” Norberg says.

Mutable Torrents and Merging Swarms
In addition, it opens up the door for peers to get the same file from multiple torrents. This is already technically possible today, as BiglyBT’s ‘swarm merging’ feature shows, but with unique file hashes, it’s easier and more reliable.

“Doing that is technically possible today, but to make it work generally for arbitrary torrents is very complicated. Having ‘per-file merkle trees’ greatly simplifies implementing this,” Norberg notes.

The same is true for so-called ‘mutable torrents’ where publishers can update torrents to add or remove files. That’s much easier with BitTorrent v2.

Finally, we should mention that it’s not just the .torrent files that will change. The v2 and hybrid magnet links are different too. And they will likely start downloading quicker, as the initial transfer of all piece hashes will be smaller. That is most noticeable when streaming or for downloading large archives.

Just how soon the v2 torrents will work depends on when clients update to the latest Libtorrent version. That can take days, but also more than a year. When large publishers and torrent sites will embrace the changes is uncertain as well, but eventually, it’s the way forward for all.


Report This Post Go to the top of the page

<< Prev  1   Next >>

You are not permitted to post in this forum.