P2P Technologies
in the Social Web
CS315 – Web Search and Data Mining
Well, maybe you can…
P2P: peer-to-peer protocol
• Compare http’s client-server model …
P2P: peer-to-peer protocol
• Compare http’s client-server model vs p2p…
• 1999: Napster created by NEU student Sean Fanning:
Every client becomes a server – no central server
Napster vs http
• Technically
– Far more efficient:
no server overload
– Far more reliable:
many machines could
crash and still the system
would operate fine
– Only maintains a
directory of files, stores
no files at all!
• Culturally
• 26 million users
in 2 years
• Napster parties
• “The universal juke box”
• 80% of campus traffic
from sharing music
• 26 million
copyright violators!?
Judge finds Napster guilty of
contributory and vicarious copyright infringement:
enabling others to infringe and not preventing them
Types of infringement
• Direct infringement
• Contributory infringement
– There has been a direct infringement by someone
– The accused contributory infringer
knew or should have known about the underlying direct infringement
– The accused contributory infringer induced, caused,
or materially contributed to the underlying direct infringement
• Vicarious infringement
– There has been a direct infringement by someone
– The accused vicarious infringer had the right or ability
to control or supervise the underlying direct infringement
– The accused vicarious infringer derived a direct financial benefit
from the underlying direct infringement
Napster is dead; Long live Napster
• 2000: Grokster, Morpheus, Kazaa get rid of central directory
RIAA vs Grockster
• Previous case: The 1984 VCR lawsuit aka “Sony-Betamax”
– Supreme Court: Even though people using VCRs may infringe,
“ the sale of copying equipment, like the sale of other articles of
commerce, does not constitute contributory infringement
if the product is widely used for legitimate unobjectionable purposes”
• 2003: The Court that ruled against Napster, dismisses suit,
providing a “safe harbor” against allegations of secondary infringement.
• RIAA appeals
• 2005: RIAA wins at the Supreme Court:
– Supreme Court: “We hold that one who distributes a device
with the object of promoting its use to infringe copyright,
as shown by clear expression or other affirmative steps taken to foster
is liable for the resulting acts of infringement by third parties”
Legal differences of Atoms vs Bits
• When you buy a book
you can
Read it
Lend it out
Resell it
Copy a portion and
quote it in a paper
• Donate it
• Open it without
How about
a DVD?
an audio CD?
Mac OS?
You can’t copy a
You can’t even play it
outside your “region”
So, can you even rip a song from a CD you bought?
So, What is Copyright?
“If nature has made any one thing less susceptible than all others of
exclusive property,
it is the action of the thinking power called an idea,
which an individual may exclusively possess as long as he keeps it
to himself;
but the moment it is divulged, it forces itself into the possession of
every one,
and the receiver cannot dispossess himself of it.
Its peculiar character, too, is that no one possesses the less,
because every other possesses the whole of it.
He who receives an idea from me, receives instructions himself
without lessening mine; as he who lights his taper at mine,
receives light without darkening me.
That ideas should be freely spread from one to another over the
globe, for the moral and mutual instruction of man, and
improvement of his condition,
seems to have been peculiarly and benevolently designed by
nature . . .”
Thomas Jefferson
The Fundamental Mechanism: A Timelimited Monopoly
US Constitution, Article 1, §8:
“The Congress shall have the power …
To promote the Progress of Science and the
Useful Arts,
by securing for limited Times
to authors and inventors
the exclusive Right
to their respective Writings and Discoveries.”
The 5 Rights of Copyright Holder
• To reproduce
– Exemption for Libraries, archives, home recordings, temp copy from the
• To prepare derivative works
– Including abstracts, enhancements, translations, digitizing text
• To distribute
– Exemptions for “face-to-face” instruction but not distance learning
• To display publicly
– Exemption for instructional broadcasting
• To perform publicly
Fair Use
Exemption to Copyright Monopoly
• The Right of the Public
to reproduce and distribute without permission for:
Criticism and Parody
News Reporting
Teaching, scholarship, Research
Home Use (off air video and audio)
• But claiming “fair use” is not granted automatically!
• Determining “Fair Use” is Subject to a 4-Factor Test
Non-profit vs Commercial Use
(Small) number of copies made
Amount of text copied
Effect of Market potential (dilution of value)
Insufficient originality
Sufficient originality
Derivative work
Intellectual Property Issues
• Copyright
– Assume everything on the web is copyrighted
including text, images, sound, video.
Requires permission from the copyright holder
to download, copy, distribute.
• Trademarks
– All famous marks are registered and watched by web crawlers,
including logos and design
Domain names that confuse origin or dilute the value of the mark
will be challenged by owners.
• Patents
– Obviously.
But for the web might be confusing
• Compton’s patent on a search method failed
but many e-commerce patents are issued.
• Trade Secrets
Copyright Basics
• What is Copyrightable
– An original work of authorship [low threshold]
that is fixed in a tangible form of medium [more than ephemeral].
– Copyright is automatic (since 1974): No special filing is required
– © symbol is advised but not required
– Ignorance is no defense against copyright infringement.
– Not Copyrightable:
Facts, ideas, titles, short phrases, public domain information
• Who owns the Copyright
– The Author
unless “work for hire” or assigned to publisher
• How long does the Copyright lasts
– By Author: Life plus 70 years
– By Employer: 95 years from publication or 120 from creation
Increasing duration of copyright
Copyrighted on the Web
Modern Text
Screenplays, books, poetry, quotes,
journals, newspaper articles
Author or publisher
Stills, video, artwork, logos
Photographer, object
owner, artist, architect,
trademark company
Performance rights, mechanical rights, Lyricist, Performer, Studio,
synchronization rights
(pictured or
Patents, university employees,
trade secrets to 3rd party
Programmer, university,
faculty, students, 3rd party
Actors, Recognizable People, have
rights of Publicity, of Privacy, against
Individuals, agents, parents