One of the challenges of the internet has always been sending files at maximum speed. This is influenced by the capacity of the network, the devices that share the file and the protocol that makes that connection possible. Hence, when the world discovered BitTorrent 20 years ago, many saw that it would be the definitive protocol for sharing large files over the internet.
BitTorrent was born at a time when internet connections were much slower than today. But although today we have 300 or 600 Mbps fiber optic connections, and some are already flirting with 1 Gbps, the size of the files has also increased. If in the beginning of Torrent files of a few gigabytes were shared, nowadays it is common to download content of several gigabytes. Just an example. The average Linux ISO was 700 MB. Today, it is common to find ISO images of 4 GB or more. And no matter how fast your connection is, the BitTorrent protocol is necessary to give it that boost that speeds up the download.
And although BitTorrent and other P2P protocols are associated with content piracy, in its 20 years of existence we have seen how producers of audiovisual content or free software projects such as Linux have used this technology to legally share files. What's more, companies like Facebook or Twitter have used BitTorrent for internal use. And what about companies like Blizzard or Steam, which have to deal with the enormous files of their games and which have found an ally in BitTorrent to send them to their users. If we take a look at the official BitTorrent page, we will see that among its most well-known users are Netflix, Google, Facebook and Twitter precisely.
The evolution of exchange networks
The BitTorrent protocol was already good in itself when it was born thanks to its creator, Bram Cohen. It allowed to share large files in a semi-centralized way. There was a server that acted as an intermediary, as occurs in other protocols such as Napster or Audiogalaxy, but the shared files are hosted on the clients' devices. And in the middle, some nodes that have the information that the server needs for everything to work.
But the great advantage of BitTorrent is that clients share fragments of files, so that the upload and download are done at a higher speed. As simple as getting a magnet link or a Torrent extension file to start the download with one of the many BitTorrent clients out there. Along the way, concepts such as leech, seed or tracker. The first, who download. The second, essential, who share the complete file. And, thirdly, the nodes or servers that facilitate the connection between each other.
BitTorrent v2, improving what is present
However, 20 years take their toll. Hence, in 2020, BitTorrent v2 emerged, the second version of this P2P protocol and that promises great improvements to adapt to the times. The specifications for this major update actually emerged in 2008, but it's only recently that we've seen its final implementation. Among the novelties, more speed if possible. And secondly, more secure connections in an internet in which security and privacy are two aspects to be protected.
On a technical level, BitTorrent v2 introduces the SHA-256 encryption, abandoning the already obsolete SHA-1. This security enhancement affects the information that makes it possible to split and rejoin the fragments of files that are shared on the BitTorrent network. On the other hand, less data is needed to start the download thanks to the branching of the information in the form of a tree or hash trees. This makes torrent files smaller. On the other hand, the download itself is faster and optimal, since fragments of other downloads can be used if they are identical. You will find all the technical information in this link that explains in detail how the library that makes BitTorrent v2 possible works.
The change to BitTorrent v2
From the user's point of view, what do you have to do to enjoy BitTorrent v2 instead of the previous protocol? To start, have a compatible client. At the time of this writing, the first client to support BitTorrent v2 was BiglyBT, although it is largely unknown despite its long list of features.
In second place we find qBitTorrent. It's not one of the most popular, but it's available for Windows, Mac, and Linux and has most of the features you'll ever need. Also, it has more popularity than BiglyBT. However, we will have to wait for support for BitTorrent v2 to reach more popular clients such as *Transmission or uTorrent, the two main ones together with BitTorrent, the client of the same name.
Another requirement to use the BitTorrent v2 protocol is to use Torrent v2 files. But that is no longer up to us. That's where those who share content through the Torrent network come in. Meanwhile, for a while both protocols will coexist . We will find Torrent files v1, v2 and also mixed or hybrid files. On the part of the clients, little by little they will incorporate support for BitTorrent v2.
