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.. Standing on the shoulders of giants: Example of Web links rotting away |
.. Standing on the shoulders of giants: Example of Web links rotting away |
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.. History of location-dependence: `TBL ref`_ (like in HT'03 paper) |
In 1997, NASA launched the Cassini-Huygens spacecraft |
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on a mission to Saturn. Before the launch, the mission |
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was widely criticized for its use of radioisotope |
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thermoelectric generators (RTGs), using plutonium |
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to generate electricity. Activists claim that |
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the launch of such devices poses a threat to |
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billions of human lives [#]_. To facilitate the debate, |
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SpaceViews, a publication of the National Space Society, |
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published a list of links to web pages of both |
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Cassini opponents and supporters [#]_. |
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.. [#] ``http://www.seds.org/spaceviews/cassini/rtg.html`` |
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.. [#] ``http://www.seds.org/spaceviews/cassini/rtgpages.html``. |
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All links dereferenced on October 27th, 2003. |
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|
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Of the 83 links provided by SpaceViews, 29 continue to work in 2003. |
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Only six years after the launch, two thirds of the debate |
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have fallen off the Web. "If I have seen further it is by standing |
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on the shoulders of giants;" but how can we do that today, |
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if the shoulders keep rotting away? |
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|
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.. Links shouldn't break when documents move or |
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publishers lose interest |
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|
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There are two reasons for broken links: Either the original |
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publisher has moved the target document to a new address, |
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or they have stopped publishing it, usually because keeping |
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up a Web page requires some amount of maintenance and they |
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have lost interest. |
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|
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We don't propose that every byte of information ever published |
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on the Web should have to be kept around forever. However, |
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we do believe that as long as someone does keep a copy, |
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data should remain accessible, and links should continue |
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to work. |
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|
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.. Location-independent, semantic-free, *self-verifying* |
.. Location-independent, semantic-free, *self-verifying* |
58 |
identifiers (ref SFR paper [balakrishnan03semanticfree]_, |
identifiers (ref SFR paper [balakrishnan03semanticfree]_, |
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[walfish03dns]_); example: hash-based (ref |
[walfish03dns]_); example: hash-based (ref |
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``hash`` URN namespace Internet-Draft; ref Freenet & others) |
``hash`` URN namespace Internet-Draft; ref Freenet & others) |
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.. History of location-dependence: `TBL ref`_ (like in HT'03 paper) |
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|
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.. Proposal: A location-independent Web (closest thing is Freenet (ref)) |
.. Proposal: A location-independent Web (closest thing is Freenet (ref)) |
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|
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.. Benefits of hash-based addressing: |
.. Benefits of hash-based addressing: |