Misplaced Pages

Memento Project

Article snapshot taken from[REDACTED] with creative commons attribution-sharealike license. Give it a read and then ask your questions in the chat. We can research this topic together.
American web preservation project For Memento use on Misplaced Pages, see Misplaced Pages:Memento.
This article has multiple issues. Please help improve it or discuss these issues on the talk page. (Learn how and when to remove these messages)
This article's tone or style may not reflect the encyclopedic tone used on Misplaced Pages. See Misplaced Pages's guide to writing better articles for suggestions. (November 2019) (Learn how and when to remove this message)
This article may be too technical for most readers to understand. Please help improve it to make it understandable to non-experts, without removing the technical details. (June 2024) (Learn how and when to remove this message)
(Learn how and when to remove this message)
[REDACTED]
The Memento logo

Memento is a United States National Digital Information Infrastructure and Preservation Program (NDIIPP)–funded project aimed at making Web-archived content more readily discoverable and accessible to the public.

Technical description

Memento is defined in RFC 7089 as an implementation of the time dimension of content negotiation. HTTP accomplishes negotiation of content via a variety of headers that allow clients and servers to find content that the user desires.

Dimensions of Content Negotiation Provided by HTTP
Request Header Response Header Dimension Examples Reference
Accept Content-Type content-type of the representation text/html

text/plain image/png

RFC 7231

RFC 2616

Accept-Language Content-Language language of the representation en

en-US cz

RFC 7231

RFC 2616

Accept-Encoding Content-Encoding medium, typically compression, that the content has been encoded with compress

gzip deflate

RFC 7231

RFC 2616

Accept-Charset Content -Type the character set used by the web page iso-8859-5

unicode-1-1

RFC. 
7231

RFC 2616

Accept-Datetime Memento-Datetime time of the representation Fri, 15 Aug 2014 13:43:03

GMT

RFC 7089

The Last-Modified header provided by HTTP does not necessarily reflect when a particular version of a web page came into existence. Also, the Last-Modified header may not exist in some cases. To provide more information, the Memento-Datetime header has been introduced to indicate when a specific representation of a web page was observed on the web.

This diagram shows how Memento uses a TimeGate (URI-G) to find the best archived page (URI-M) for a user, given the original resource (URI-R) and a datetime.
This diagram shows how Memento uses a TimeGate (URI-G) to find the best archived page (URI-M) for a user, given the original resource (URI-R) and a datetime.

Usage

Copies of page can be found by simply navigating, in a web browser, to a link formatted, replacing urltoarchive with the full URL of the page desired:

JSON description of a Memento:

http://timetravel.mementoweb.org/api/json/YYYY/urltoarchive
http://timetravel.mementoweb.org/api/json/YYYYMM/urltoarchive
http://timetravel.mementoweb.org/api/json/YYYYMMDD/urltoarchive
http://timetravel.mementoweb.org/api/json/YYYYMMDDHH/urltoarchive
http://timetravel.mementoweb.org/api/json/YYYYMMDDHHMM/urltoarchive
or

redirect to a Memento with a datetime that is close to a desired datetime:

http://timetravel.mementoweb.org/memento/YYYY/urltoarchive
http://timetravel.mementoweb.org/memento/YYYYMM/urltoarchive
http://timetravel.mementoweb.org/memento/YYYYMMDD/urltoarchive
http://timetravel.mementoweb.org/memento/YYYYMMDDHH/urltoarchive
http://timetravel.mementoweb.org/memento/YYYYMMDDHHMM/urltoarchive

References

  1. RFC 7089: HTTP Framework for Time-Based Access to Resource States -- Memento
  2. Berners Lee, Tim. "Web Architecture: Generic Resources". World Wide Web Consortium (W3C). 1996. http://www.w3.org/DesignIssues/Generic Archived 2015-06-02 at the Wayback Machine
  3. RFC 7231: Hypertext Transfer Protocol (HTTP/1.1): Semantics and Content
  4. RFC 7232: Hypertext Transfer Protocol (HTTP/1.1): Conditional Requests
  5. Nelson, Michael L. "2010-11-05: Memento-Datetime is not Last-Modified". Web Science and Digital Libraries Research Group. November 5, 2010. http://ws-dl.blogspot.com/2010/11/2010-11-05-memento-datetime-is-not-last.html Archived 2015-05-19 at the Wayback Machine
  6. "Time Travel APIs". timetravel.mementoweb.org. Archived from the original on 2018-05-21. Retrieved 2018-05-15.

External links

Categories:
Memento Project Add topic