Justin's Report on BitTorrent

Justin Wickett
2/28/07
Duke 2010

Apple and BitTorrent: A Disaster Waiting to Happen…

As the market for HD-DVDs is on the rise, Apple must come up with an efficient
means of distributing content to their end users. Although many different techniques are
under investigation, BitTorrent has become one of the preferred methods. Currently, any
iTunes user can log in to their account to access the wealth of data stored on Apple’s
servers available for download. By implementing a BitTorrent style system, Apple would
be essentially redesigning their existing system by storing small bits and pieces of files on
their user’s computers. After researching BitTorrent in detail and carrying out various
experiments, I believe that Apple should continue to offer their iTunes store without
incorporating BitTorrent technology.
Apple’s FairPlay DRM is one of the main reasons why BitTorrent is an unfeasible
solution to the issue of HD distribution. Apple encrypts the video content available from
within the iTunes store as protected MPEG-4 files, which require a user key to decrypt.
When a user makes a purchase at the iTunes store, they are essentially using their own
unique key to scramble a file that contains a master key. Only the user with access to this
key can unscramble the file afterwards. Because the way the system is currently set up, it
is impossible to use BitTorrent to access content that has been encrypted by a wide
variety of different user keys. Due to the fact that BitTorrent downloads small portions
from all nearby users, if someone were to download a chunk of data from each uniquely
scrambled file, they would end up having unplayable content. In order to make use of
BitTorrent, Apple would have to come up with a new means of encryption so that all
portions of the file work together.
The lack of simplicity is yet another reason why BitTorrent is not a suitable
replacement. Users who choose the iTunes Store have certain expectations and desire a
straightforward experience. Most torrent applications do not incorporate a dynamic hash
table, thus users are forced to locate and download the torrent they desire to supply the
application with the relevant metadata, tracker, etc... This procedure does not embrace
simplicity, and has the potential to turn many customers away from using Apple’s
product to download HD content.
Constant performance is also lacking on BitTorrent overlaying networks. Even
though popular torrents download at high rates because of large swarms of users storing
and sharing bits of content, as the torrents get older, swarms disappear and seeds have
fewer reason to continue offering their complete version to the rest of the community.
The result is that it takes a shockingly long time to download older and less popular
media using BitTorrent. While the Apple iTunes Store might never reach the download
rate peaks BitTorrent users experience, it doesn’t suffer from the extremely slow rates
exhibited when only one person is a seed. Customers expect constant performance for all
types of media. I did a test comparison to determine whether or not BitTorrent allowed
me to download “The Hunt for Red October” any faster than the traditional iTunes Store.
I was shocked to discover that my 1.46GB download took merely 9 minutes, and even
more amazed to see that my BitTorrent client informed me that I had 17 hours remaining.
Even though “The Hunt for Red October” is an older movie released in 1990, the fact that
my BitTorrent client was only able to connect to 7 seeds is unacceptable. On top of that, I
was able to watch my video from iTunes while it was in the process of downloading,
which is impossible in BitTorrent due to bits and pieces arriving out of order.
BitTorrent also violates people’s privacy by forcing users to allow uploads in
order to enjoy high download rates. People who purchase content from Apple have the
right to keep their transaction confidential. However, BitTorrent would attempt to
download private content from nearby seeds without first seeking their approval. Apple
iTunes already offers adult-oriented material, and as adult oriented HD-DVDs become
increasingly popular, people may not want to disclose to nearby nodes their entire library.
In a BitTorrent system, someone who attempted to download pornographic content could
see all of the nearby seeds that have already purchased it due to the way IP addresses are
disclosed. This could lead to very embarrassing situations and privacy violations, which
could result in potential lawsuits.
While BitTorrent does provide its users with many benefits, Apple’s conventional
method of distributing media content to purchasers seems to work very well. While a
single layer HD-DVD is capable of storing up to 15GB of content, Apple must dedicate
more hardware and bandwidth to ensure that their customers can enjoy fast download
speeds. Requiring users to rely on a BitTorrent client adds complexity and is counter
productive to Apple’s end goal of being the number one HD-DVD distributor.

Sources:
http://online.wsj.com/public/article/SB112199964473193071-
wHD0jEWmn1XrxuhE5HgGCs4siD0_20060721.html?mod=tff_main_tff_top
http://www.tracktrap.com/whatis.php
http://portal.acm.org/citation.cfm?id=1015508
http://www.roughlydrafted.com/RD/RDM.Tech.Q1.07/2A351C60-A4E5-4764-A083-
FF8610E66A46.html