Cryptography Reference
In-Depth Information
MP3 is short for MPEG-1, layer 3, where MPEG is the acronym for Motion
Picture Experts Group, which operates under the direction of the ISO and
IEC (see Footnote 9.26 on page 354), for the development of standards for
audio/video compression. In 1988, MPEG met to consider the development
of a single codec (compression/decompression) for digital audio. By 1992, the
MPEG-1 standard for audio and video coding was created. The new standard
produced high-resolution audio compression data in packets vastly smaller than
those required for the WAV format. By 1997, an inexpensive software for MP3
was delivered, and this new format is what made it quick and easy to download
pirated music stolen from copyrighted CDs. The MP3 compression ratio is
about 12:1, meaning that the size of an MP3 clip is one-twelfth the size of an
uncompressed audio file. More importantly, MP3 compresses without sacrificing
much quality. It does this through a process called perceptual audio coding
scheme that relies on the property of the human ear to discard the weakest
sounds. For MP3, this means that there is a loss in quality, but the loss is not
perceived by the human ear!
In October of 1998, the MP3 sensation was given a publicly available com-
mercial vehicle, called the Rio marketed by Diamond Multimedia, as a portable
MP3 player. Initially, users could upload music to certain key sites, such as
MP3.com . Then anyone could go to that site and download it from the server
where it was stored, but the user had to search the Internet for the desired
music. Sometimes, IRC (see Footnote 10.30 on page 406) could be employed to
chat with others and find an appropriate site. However, a combination of all
these functions would have to wait for the idea of a single teenager.
Napster : In 1999, eighteen-year-old Shawn Fanning, a Northeastern Uni-
versity student, wrote a program that combined three features:
1. A search engine which was dedicated to finding only MP3 files.
2. File sharing, providing the ability to exchange MP3 files directly, thereby
eliminating the need to store them on a server.
3. IRC embedded as part of the program to allow MP3 users to chat online.
The above program became the utility called Napster , which was a high-
school nickname for Fanning, ostensibly derived from his hair. Napster replaced
the server storage mechanism with peer-to-peer sharing. Thus, with Napster, a
user would be downloading music from another user's computer, which could be
anywhere in the world. The manner in which this was accomplished is explained
in what follows.
Suppose that Alice wants to share music over the Internet. In order to use
Napster she needs the following:
1. A copy of the Napster utility installed on her computer.
2. A directory on her computer whose privilege she sets to shared mode.
3. An Internet connection set to be on.
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