Sunday 29 June 2008

A complete guide to torrent downloading :o)

What is a Torrent file?

A torrent is a computer file, which contains information about another file or a group of files. These details include name, size, date of creation, a unique info-hash (code for the torrent) and tracker-information. None of the other torrent files on the internet would have the same info-hash ID. In short, the torrent acts as a collection of information, which points towards a file or group of files residing on a number of PCs across the internet.

What is a Tracker?

A tracker is a computer on the internet, which does a real-time management of a torrent. So whenever a user opens a torrent on his PC using a Bit Torrent client, this client connects to a tracker, which in turn tells the client two things (a) How much %age of the file does the client's PC have and (b) location of all the PCs in the world, who are currently connected to this tracker. For example, if you open a torrent for a movie, the client on your computer will come to know the address of many other users, who are having the same movie and are sharing it. It would then help the Bit Torrent client to connect to those users and download the movie on to your PC.

What is a Bit Torrent Client

A Bit Torrent client is required to open a .torrent file. It simply works like any other software... For example, if you want to open a Word Document, you would need a software such as MS Word... Having the Word Document (.doc) file alone won't help you open it.

What are some of the most popular Bit Torrent clients:
  1. uTorrent - The most efficient and least resource-consuming Bit Torrent Client
  2. BitComet - A fast-growing Bit Torrent client, which also uses the CometZone technology to connect users, who are using BitComet, in addition to connecting users, who are using Torrent
  3. Vuze (earlier Azureus) - A Java based Bit Torrent clients, which presents the user with an excellent interface in the form of a user-friendly Dashboard and also an Advanced feature for power-users

Let's get started on Torrents!

So, let's get started on how to use the Torrent technology to download stuff from the internet!

Here are the following steps:

  1. Download a Bit torrent client from the internet. You can choose one of the torrent-clients listed above or download a client of your choice. Download uTorrent from http://www.utorrent.com/download.php. Many Bit Torrent clients are heavy on system-resources and may considerably slow down your computer. Therefore, be careful on which client you are downloading. I recomment uTorrent.
  2. Install the Bit Torrent client on your computer
  3. Configure the Bit Torrent client. Select "Preference" from the "Options" menu:



- Select "Directories" and in the first two check boxes, mention the location on your PC, where you would like to download content using Bit Torrents.







- Select "Connection" and (i) In the field, "Port used for incoming connections", mention a 5-digit long port number and (ii) make sure that the option "Enable NAT-PMP port mapping" is selected







- Select "Bandwidth" and ensure that the option "Automatic" is selected. Unless you are an advanced user, do not change this option
- Maximum download rate : Let it be '0' only
- Global number of connections - Unless you have a fast connection such as 1 MBPS or more, keep this setting less than 120 (as many connections will be established to your PCs as the number and it may slow down your PC)
- Maximum number of connected peers per torrent : For 256 KBPS, keep the setting to 50, for 512 KBPS, keep the connection to 75 and for 1 MBPS, keep it to 100





- Select "Queueing". Maximum number of active torrents (upload or download).
a) Maximum number of active torrents : This signifies the total number of active torrents (both downloading and uploading under both finished and incomplete downloads). Mention '5' if you have a connection, which is 256 KBPS, '6' if you have 512 KPS and '12' if you have 1 MBPS connection
b) Maximum number of active torrents: under this field, mention '3' if you have a connection, which is 256 KBPS, '5' if you have 512 KPS and '9' if you have 1 MBPS connection. Mentioning more number here would result in de-prioritization and contents would take more time to complete as bandwidth and download speed will get distributed amongst more torrents.





- Select "Advanced" - Hack the max half-open TCP connectionsIf you are on XP sp2, your TCP connections are limited to a maximum of 10. This might hurt your downloading speed because it wont let you connect to as much peers as you want. It is supposed to slow down viruses because their spreading strategy is to connect to a high amount of ip numbers, but it could cripple your torrent downloads. A nice way to fix this is to download a patch from http://torrentfreak.com/evid4226patch223d-enzip/


Note: Some people report that their antivirus reports the patch to be a Virus, This is not the case. Check out http://www.lvllord.de/ for more details on this.

The patch allows you to set the maximum allowed connections to any number you want. Any number between 50 and 100 is ok (more is NOT always better). Next you need to configure your torrent client to allow 50-100 max half-open TCP connections.

Go to Options > Preferences > Advanced options > net.max_halfopen





Setting uTorrent for your speed

Now Go to Options > Speed Guide, shown below


Select the listing closest to your upload speed result (rounding down as necessary). The speed test results may not be spot-on so if there isn't a criteria that fits in exactly with your speed, choose the closest. A difference of 10% can't hurt. You will notice that the "Affected Settings" further down the page have adjusted to match your selected speed. Higher settings will not give you better speed, and may in fact make speeds worse. Click the "Use Selected Settings" button at the bottom of the Speed guide window. It is also best if you choose a port number above 10000 (the one used here is 39272).

The best way to speed up your downloads!
You would have to open one "incoming port" on your "Router". This applies to those users, who use broadband connection with a Mode/Router... You would need to go to the "Admin" page of the router and open one "incoming port".

The port number, which you specify in your Router-settings, needs to be mentioned in the box circled in the screen-shot shown just above this paragraph (it shows 39727 because that is the port, which has been opened on the router)

Please refer to the "configuration guide" or "user guide" of your Router. If you are having a Siemens (speedstream) router, you can contact me and I could help you on how to do that.