Here’s a great essay explaining why people shouldn’t put RAR archives in torrents. They are useless and they make “selective downloading” impossible.
Found at The Piratebay
Why RAR archives do not belong in torrents
It has become a common practise to create torrents which contain umpteen RAR files, often in the form of a Release from The Scene, instead of simply directly adding the actual files to be distributed.
Though some might think this practise lends a bit of underground mystique to the common BitTorrent world, that is the only thing that might possibly be said in its favour. Others think the use of RAR solves some real problems. The truth is it adds nothing but nuisance
and even renders a useful feature of BitTorrent clients useless.
This essay aims to explain why it is a good idea to extract your
RAR archives before creating a torrent.
Why are there umpteen RAR files to begin with?
This essay is not trying to argue that sceners should change the way they package their releases. As a common BitTorrent user, the author couldn’t care less. Since sceners transfer their files by other means than BitTorrent, there really are some problems that are
solved by the elaborate packaging.
The first problem is that of files being corrupted in transfer. One of the features of the RAR format is the use of checksums to ensure file integrity. If a RAR file is damaged in transit, the idea is that thanks to the checksum you will notice this when the archive is extracted, so that you will not unknowingly end up with a corrupted file.
The second problem is that of re-downloading when something goes wrong. With the use of multi-volume archives (that’s the umpteen .r01 and so on files) you don’t have to download the whole thing again. However, RAR checksums are not very practical for multi-volume
archives. Which is why releases also come with .sfv files containing checksums for each individual RAR file.
The third problem is that many file transfer protocols do not support the parallel downloading of one file from multiple sources. Multi-volume archives let you work around this manually.
BitTorrent solves these problems for you
Most people know that solving the third problem, parallel downloading from multiple sources, is the very essence of BitTorrent. That multi-volume RAR archives are still common in torrents suggests that some have missed the fact that BitTorrent also takes care of the
first and second problem for you. And it does this automatically, without requiring any other tools. What the sceners do manually, the BitTorrent users need not bother with.
Each .torrent file includes information on how to split the files being distributed into many smaller pieces that can be transferred individually, even out of order. This is much like the multi-volume RAR archives, although the pieces are smaller and you never have to deal with them yourself. So when a scener might have to manually re-download a file of several megabytes, the BitTorrent user doesn’t even notice that their client automatically re-downloaded a few kilobytes when needed. Your BitTorrent client can do this, because
the .torrent file also comes with checksums for each little piece. (Checksums which, by the way, are created using a much better algorithm than that used in .sfv files). That is how BitTorrent also solves the first and second problem for you.
What RAR archives in torrents really achieve
So if BitTorrent already takes care of the problems the RAR archives was supposed to solve, what do they really achieve? To begin with the obvious, before you can use the files you just downloaded, you must extract them. Since practically all of the material
distributed with BitTorrent comes in compressed formats to begin with, like music and movies, the little compression RAR adds is useless. Instead you need twice as much free disk space. First for the RAR archives and then again for the extracted files. And if you want to
play nice and seed for a while like you should, you must keep the RAR files around.
But it gets worse. Sometimes you don’t want all of the files in a torrent. A good BitTorrent client lets you download just the files you want. But if the torrent contains a RAR archive, you must download it all anyway to eventually get the files you really want.
So to summarise, RAR archives in torrents waste disk space and hinder useful BitTorrent client features, without adding anything of value. In other words, they are a useless pain in the ass.
But The Scene has rules, and RAR is cool!
Face it, if you get your warez with BitTorrent, you’re not part of The Scene. And that goes for the people that will download your torrents as well. They will not care about rules or archive formats. What they will care about is if you waste their time and disk space.
What about NFO files and credit?
That’s simple. If you care about giving credit where credit is due, don’t rename the files you extracted from the RAR archives. And let any .nfo files be part of the torrents you create as well. But keep the useless stuff like .sfv files and samples out. Who needs samples when you can just open the file directly?
By Anonymous 2005. Verbatim copying and redistribution of this essay
are permitted provided this notice is preserved.