Technical Question

[poiuuiop]

Hi,

When a new file is made available on BT, who/what is the process that is used to split/fragment it into smaller parts?

I assume that some sort of a program is needed to split a file, give each of its components some identifier, create some information needed to sequence it back, create the .torrent file, assing the tracker, etc.

[{I}{K}{E}]

You can use winrar to split a file into smaller parts.

[poiuuiop]

SO, does one need to use some utility (like Winrar) first to split, before being able to offer it using BT?

My question is:
(1) does BT provide a native way to create the fragments. I think it does, because i always read about the 'typical' size of a file segment.
(2) do apps that offer the ability to publish on BT (writtorrent, etc) have such an utility built into them as well?
(3) what are some popular apps that allow one to create a .torrent?

[i_will]

Yeah, you need winrar first if you want to split up a large file. There's a conventional size for the files, I have no idea what it is though, 15 megs?? No idea about the rest of your questions though.

[zeustke165]

First off the winrar issue, generally you want to crete less than 100 rar segmants per torrent, so the general rule of thumb is 15 meg pieces or files under 1 gig, 50 mege for between 1 gig and 4.7 gig, and 100meg for anything over 4.7

Second using maketorrent it does not phisically split the file into fragments but rather tells what portion of a file is what piece number, this is done automatically by the torrent creation program, the only thing that the user can do is select what the piece size should be, or you can leave that up to maketorrent as well... and as you may have figurede out maketorrent is a great program for making torrents...

Zeus

[4play]

the file is never physically split up.
btmaketorrent will take a specific amount of data from the file and create a sha1 hash which generally look like this c245e8d992aac2f0f7b8b19a6d31756ce23a9df1. it carries on doing this until its reaches the end of the file. when you download any particalar chunk the hashes are then compaired. if they match the data is fine and it moves on to another chunk. if they dont match it disgards the data and downloads it again.

[proffe]

New question... When i make a new torrent with maketorrent2, the file size only are 5 kb, is that rigth? Maybe a stupid question, but it's the first time i try it.... Thanks....

[lynx]

The size of the torrent file is entirely dependent on the number of pieces.

In theory you could have a 10GB torrent with only one piece, the torrent file would be very small, but it would be virtually useless to anyone (and I'm not sure if maketorrent would let you do it anyway).

At the other extreme you could have a 10GB torrent with 10 million pieces of 1k. Since each piece has a 20 byte hash the torrent file would be over 200MB!!! Again I'm not sure if maketorrent would let you do it.

I'm guessing that your 5k torrent file has about 200 pieces (there's other info in the torrent too) but there's no way for anyone to say that it is right without a lot more info.

[proffe]

Okay thanks....!