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[Gzz-commits] manuscripts/pointers article.rst
From: |
Benja Fallenstein |
Subject: |
[Gzz-commits] manuscripts/pointers article.rst |
Date: |
Sat, 01 Nov 2003 16:23:39 -0500 |
CVSROOT: /cvsroot/gzz
Module name: manuscripts
Branch:
Changes by: Benja Fallenstein <address@hidden> 03/11/01 16:23:39
Modified files:
pointers : article.rst
Log message:
more about file-sharing in intro, cut some crud from it
CVSWeb URLs:
http://savannah.gnu.org/cgi-bin/viewcvs/gzz/manuscripts/pointers/article.rst.diff?tr1=1.58&tr2=1.59&r1=text&r2=text
Patches:
Index: manuscripts/pointers/article.rst
diff -u manuscripts/pointers/article.rst:1.58
manuscripts/pointers/article.rst:1.59
--- manuscripts/pointers/article.rst:1.58 Sat Nov 1 16:10:43 2003
+++ manuscripts/pointers/article.rst Sat Nov 1 16:23:39 2003
@@ -85,6 +85,15 @@
and increase availability. However, if the Web worked like
a file-sharing system, Web pages could never be updated.
+While many file-sharing systems provide URIs
+for particular versions of a file, using cryptographic hashes
+(e.g., [XXXrefs]), these files cannot be updated;
+a new version would have a different hash, and thus
+a different URI. In file-sharing systems, updating
+would be useful for media files like the e-books
+distributed by Project Gutenberg [XXXref], which
+are occasionally updated to fix typographic errors.
+
XXX
.. Standing on the shoulders of giants: Example of Web links rotting away
@@ -133,43 +142,32 @@
History of location-dependence: `TBL ref`_ (like in HT'03 paper)
-This can be accomplished by replacing URIs that include
-a server name by URIs that are
+.. <<<This can be accomplished by replacing URIs that include
+ a server name by URIs that are
-- location-independent: do not refer to a particular server
- that the file is to be downloaded from;
-- semantic-free: don't include human-readable information;
- if an identifier is semantic-free, there is no incentive
- to change it when a site is re-designed;
-- self-verifying: after downloading an alleged copy of a document,
- there is a cryptographical algorithm to test whether
- this is *really* a copy of this document.
-
-The most prominent example are cryptographic hashes.
-A file identified by a cryptographic hash
-can be downloaded from any server that has a copy; the client
-can then check the integrity of the file by checking it against the hash.
-
-.. <<<Self-verifying means that given the identifier and a file,
- a client can check that the file matches the identifier.>>>
-
-.. <<<(If the hashes do not match, the client can try a different server.)
- This way, a page's URI never needs to change.>>>
-
-In 1996, Tim Berners-Lee [name-myth]_ argued that
-using location-independent, semantic-free identifiers
-is not viable on a global scale:
-"[I]f you put information in a name, it decreases its longevity;
-if you don't you can't dereference it to a resource."
-
-However, as observed in [fallenstein03storm]_,
-with the advent of efficient peer-to-peer lookup mechanisms such as
-distributed hashtables (DHTs), this observation
-is no longer true. A DHT is quite able to resolve a
-hash-based identifier on a global scale,
-as evidenced by applications like the Cooperative
-File System (CFS, [dabek01widearea]_) and
-the Overnet file sharing client [overneturl]_.
+ - location-independent: do not refer to a particular server
+ that the file is to be downloaded from;
+ - semantic-free: don't include human-readable information;
+ if an identifier is semantic-free, there is no incentive
+ to change it when a site is re-designed;
+ - self-verifying: after downloading an alleged copy of a document,
+ there is a cryptographical algorithm to test whether
+ this is *really* a copy of this document.>>>
+
+.. <<<In 1996, Tim Berners-Lee [name-myth]_ argued that
+ using location-independent, semantic-free identifiers
+ is not viable on a global scale:
+ "[I]f you put information in a name, it decreases its longevity;
+ if you don't you can't dereference it to a resource.">>>
+
+.. <<<However, as observed in [fallenstein03storm]_,
+ with the advent of efficient peer-to-peer lookup mechanisms such as
+ distributed hashtables (DHTs), this observation
+ is no longer true. A DHT is quite able to resolve a
+ hash-based identifier on a global scale,
+ as evidenced by applications like the Cooperative
+ File System (CFS, [dabek01widearea]_) and
+ the Overnet file sharing client [overneturl]_.>>>
.. SFR (semantic-free referencing) not all that close,
though semantic-free idea shared (SFR takes along
@@ -188,9 +186,6 @@
.. Proposal: A location-independent Web <<<(closest thing is Freenet (ref))>>>
-We propose, then, to build a location-independent Web
-based on self-verifying identifiers.
-
.. <<<The project that is currently closest to this goal is Freenet,
a XXX>>>
@@ -203,18 +198,6 @@
- Verifiable
- Same namespace for local and for non-local data
-Using hash-based addressing in such a scheme has several benefits:
-
-- Pages can be moved between servers without breaking links.
-- Links continue to work as long as *anybody* keeps a copy
- of their targets, even if the original publisher does not
- maintain the Web page any longer.
-- Downloaded files can keep their global identifiers.
- Links between two downloaded Web pages automatically work.
-- It is possible to implement load-balancing schemes in which
- a user downloads a page from anybody who happens to have a copy.
-- Different networks can be used to download a file. XXX
-
.. <<<Other projects exploit some of the advantages of hash-based
(storage systems: CFS, PAST; web caching: Squirrel),
but don't address the Web.>>>
@@ -231,13 +214,6 @@
.. However, there's a problem with this: versioning -----
Basic problem: Hash-based addressing allows no updates
-However, a document refered to by a cryptographic hash
-can obviously not be changed (without making it a different document,
-refered to by a different hash). For most Web pages, this is not
-acceptable [#academic-articles-hashlinking]_. In this paper,
-we examine solutions to this problem that keep the desirable properties
-of hash-based addressing.
-
.. Contributions; structure of this paper ----
.. Main contrib: Pointer records for implementing updating
@@ -614,12 +590,12 @@
.. [#rtg-links] ``http://www.seds.org/spaceviews/cassini/rtgpages.html``.
All links dereferenced on October 27th, 2003.
-.. [#academic-articles-hashlinking] A notable exception
- may be academic articles, in which references to other articles
- are ideally to an immutable version, and in which references
- are generally not circular, making this domain map neatly
- to the properties of hash-based referencing.
- XXX Except for "in press", "unpublished manuscripts", ...
+.. .. [#academic-articles-hashlinking] A notable exception
+ may be academic articles, in which references to other articles
+ are ideally to an immutable version, and in which references
+ are generally not circular, making this domain map neatly
+ to the properties of hash-based referencing.
+ XXX Except for "in press", "unpublished manuscripts", ...
- [Gzz-commits] manuscripts/pointers article.rst, (continued)
- [Gzz-commits] manuscripts/pointers article.rst, Benja Fallenstein, 2003/11/01
- [Gzz-commits] manuscripts/pointers article.rst, Tuomas J. Lukka, 2003/11/01
- [Gzz-commits] manuscripts/pointers article.rst, Benja Fallenstein, 2003/11/01
- [Gzz-commits] manuscripts/pointers article.rst, Benja Fallenstein, 2003/11/01
- [Gzz-commits] manuscripts/pointers article.rst, Benja Fallenstein, 2003/11/01
- [Gzz-commits] manuscripts/pointers article.rst, Benja Fallenstein, 2003/11/01
- [Gzz-commits] manuscripts/pointers article.rst, Benja Fallenstein, 2003/11/01
- [Gzz-commits] manuscripts/pointers article.rst, Benja Fallenstein, 2003/11/01
- [Gzz-commits] manuscripts/pointers article.rst, Benja Fallenstein, 2003/11/01
- [Gzz-commits] manuscripts/pointers article.rst, Benja Fallenstein, 2003/11/01
- [Gzz-commits] manuscripts/pointers article.rst,
Benja Fallenstein <=
- [Gzz-commits] manuscripts/pointers article.rst, Benja Fallenstein, 2003/11/01
- [Gzz-commits] manuscripts/pointers article.rst, Benja Fallenstein, 2003/11/01
- [Gzz-commits] manuscripts/pointers article.rst, Benja Fallenstein, 2003/11/01
- [Gzz-commits] manuscripts/pointers article.rst, Benja Fallenstein, 2003/11/01
- [Gzz-commits] manuscripts/pointers article.rst, Benja Fallenstein, 2003/11/01
- [Gzz-commits] manuscripts/pointers article.rst, Benja Fallenstein, 2003/11/01
- [Gzz-commits] manuscripts/pointers article.rst, Benja Fallenstein, 2003/11/01
- [Gzz-commits] manuscripts/pointers article.rst, Benja Fallenstein, 2003/11/01
- [Gzz-commits] manuscripts/pointers article.rst, Benja Fallenstein, 2003/11/01
- [Gzz-commits] manuscripts/pointers article.rst, Benja Fallenstein, 2003/11/02