How Torrents Work?

Torrents are a type of file sharing network. Its is similar to P2P networking but has more advantages over a normal P2P network. To understand how Torrents are different from P2P and how they better them and to make best use of Torrents read below.

During the start of file sharing in Internet there was only one way to share files among multiple users.

• To Host them in a Common Server and show the link to the file to the user.

This was easy to do. But it had some problems with this approach.

• Normal users cannot share files using such methods. If they have to do it, they have to buy server space which costs huge
• The load on server increases drastically and it affects server's performance. Especially if the file size is large.
  

In order to solve this problem, a new form of networking was designed. This is was called Peer-2-Peer networking. In this method, a set of PCs are interconnected via special software and they share the files they have in there system across a common cloud. Every system in this cloud acts both as server and as client.

When a user searches for a file, the application sends a search request to all the available nodes and gets back the search results. Based on the search result, the user will select to download a particular file. This file will be then be downloaded from the source. If the same file is available from multiple sources, then a copy of the file is downloaded from each source. Once a valid version of the file has been successfully downloaded, all the other downloads are stopped.

This method was easy and fulfilled the requirements of all users. It allowed them to share files with multiple users without the need to find a server for hosting the file.

Everything was going fine. One day Antivirus sites started alerting that there are viruses spreading through P2P networks. But how? We are only sharing files right?

Obviously. These files were forged by the Hackers. Hackers made some modifications in the actual code of P2P applications and made them to react different. When other users search for a file, these cracked applications return forged results. They pretend that the have a copy of the file you are searching for.

This might make you to download the files from those forged servers. You might be assume that you are downloading the correct file. But in real its a copy of the virus you are downloading. This flaw in P2P made a big blow to to P2P networks.

This issue was accompanied by the huge bandwidth used by these applications to download a single file. This made some users unhappy. The result, find another Technology.

Lets see how Torrents handle the issues faced by P2P networks.

Each file shared using torrents is split into multiple fragements. Each fragement is given a unique id. When a torrent file is opened, it gets a list of peers downloading the file or which already have the file downloaded. The application then pings these clients and asks them for available fragements. These individual fragements are then downloaded from individual clients. Instead of downloading multiple copies of files, we are downloading multiple fragments from multiple clients. So ultimately the bandwidth used is equal to downloading the file from a sigle client.

The torrent file we used to open has information about all the fragments of the shared files. This information also includes the hash map of each fragment. So, once the fragment is completely downloaded, its hashmap is calculated and is matched with the one in the torrent file. If they match the fragment is accepted. If they don't match the file is dropped.

And the IP from which the fragment was downloaded is noted. If there are a lot of invalid fragments from a particular system. Then that system is marked as blocked. This will prevent further download from that peer.

Since the files cannot be forged without changing their hashmap it is really hard to forge the files in torrents. Thus torrents offer more security.

So now you might have got a clear picture of Torrents and how they work. Its now time for some tips to increase your speed in torrents.

1. If you are creating a torrent, you can modify the default size of each fragment and make is a bit small. This will make the fragments to be downloaded faster and less chance of getting error. Don't reduce the size to very low value. This will split the file into huge number of fragments and the time needed for connecting to other peers for each fragment will increase the time needed for completing the download.

2. Share the files even after the download is complete. This will help keep the torrent alive for a longer time.

3. To know more about how to download create new Torrents see the Hub How-do-I-distribute-a-file-using-Torrent-sites.

4. To speed up your Torrents try this Hub How-To-Speed-Up-Torrent-Downloads.

5. Learn How-to-Use-Bit-Torrent-Files.

6. For a ccomplete jargon on Torrents refer to BitTorrent-Lexicon--An-explanation-of-P2P-file-sharing-terms-like-Torrent-Seeders-Leetch-Peers-Tracker-Reseed-etc.