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has fallen off the Web. "If I have seen further it is by standing |
has 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, |
on the shoulders of giants;" but how can we do that today, |
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if the shoulders keep rotting away? |
if the shoulders keep rotting away? |
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The Internet Archive's Wayback Machine [waybackmachine]_ |
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alleviates these concerns somewhat, but it introduces |
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a single point of failure-- and censorship-- for the *entire* Web! |
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.. [#rtg-links] ``http://www.seds.org/spaceviews/cassini/ rtgpages.html``. |
.. [#rtg-links] ``http://www.seds.org/spaceviews/cassini/ rtgpages.html``. |
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All links dereferenced on October 27th, 2003. |
All links dereferenced on October 27th, 2003. |
181 |
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(The Internet Archive's Wayback Machine [waybackmachine]_ |
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alleviates these concerns, but it introduces |
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a single point of failure-- and censorship-- for the *entire* Web!) |
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.. <<<We don't propose that every byte of information ever published |
.. <<<We don't propose that every byte of information ever published |
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on the Web has to be kept around forever. However, |
on the Web has to be kept around forever. However, |
184 |
we do believe that as long as someone does keep a copy, |
we do believe that as long as someone does keep a copy, |
193 |
Web cannot archieve, through the novel combination of |
Web cannot archieve, through the novel combination of |
194 |
network transparency and location independence (ref ourselves). |
network transparency and location independence (ref ourselves). |
195 |
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|
196 |
The main contribution of our paper are *pointer records*, |
The main contribution of this paper is the use of *pointer records*, |
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a versioning mechanism which is similar to OceanStore's heartbeats, |
a versioning mechanism which is similar to OceanStore's heartbeats, |
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but makes the clients download and store the pointer records |
but allows the clients to download and store the pointer records |
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along with the corresponding version of a document. |
along with the corresponding version of a document. |
200 |
If a client saves a version of a document locally, it |
If a client caches a version of a document locally, it |
201 |
stores the pointer record along with it. Thus, in our system, |
stores the pointer record along with it. |
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a version of a document truly remains accessible as long as |
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anybody keeps a copy of it. |
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Instead of having a primary replica, we search |
Instead of having a primary replica, we search |
203 |
a P2P network for current pointer records |
the P2P network for current pointer records |
204 |
related to a document; we pick the one with |
related to a document; we pick the one with |
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the most current timestamp as the version |
the most current timestamp as the version |
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to show to the user. Like in OceanStore, old |
to show to the user by default; old versions |
207 |
versions remain fully accessible (as long as somebody |
remain equally accessible |
208 |
keeps a copy). |
as long as |
209 |
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anybody keeps a copy. |
210 |
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211 |
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.. Like in OceanStore, old |
212 |
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versions remain fully accessible (as long as somebody |
213 |
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keeps a copy). |
214 |
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215 |
We propose to use pointer records along with hash-based |
We propose to use pointer records along with hash-based |
216 |
addressing to implement a P2P-based replacement |
addressing to implement a P2P-based replacement |
217 |
for the static Web (not including dynamic pages |
for the Web (not including dynamic pages |
218 |
generated through server-side scripting). Such a Web |
generated through server-side scripting). Such a Web |
219 |
would have the benefits of semantic-free referencing-- |
would have the benefits of semantic-free referencing-- |
220 |
URIs don't have to change because of trademark conflicts |
URIs don't have to change because of trademark conflicts |
221 |
as in DNS, for example-- but go beyond the proposal |
as in DNS, for example-- but go beyond the proposal |
222 |
by Balakrishnan et.al. [balakrishnan03semanticfree]_, which would only |
by Balakrishnan et.al. [balakrishnan03semanticfree]_, |
223 |
replace DNS, but keep the centralized architecture of |
for replacing DNS but keeping the centralized architecture of |
224 |
one Web server (or a single set of servers) maintained |
one Web server (or a single set of servers) maintained |
225 |
by the publisher of a document. |
by the publisher of a document. |
226 |
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|
227 |
The remainder of this paper is structured as follows. |
The remainder of this paper is structured as follows. |
228 |
In Section 2, we introduce pointer records. |
In Section 2, we introduce pointer records. |
229 |
In Section 3, we propose a simple, hash-based data model |
In Section 3, we discuss the minimal hash-based data model required |
230 |
that can be used by P2P Web servers and clients. |
for implementing pointers. |
231 |
In Section 4 we discuss other possible applications |
In Section 4 we discuss other possible applications |
232 |
of pointer records, and Section 5 gives an overview of our |
of pointer records, and Section 5 gives an overview of our |
233 |
implementation. Section 6 concludes. |
implementation. Section 6 concludes. |