> ## Content Index
> Fetch the complete content index at: https://www.lorcandempsey.net/llms.txt
> Use this file to discover other available public pages before exploring further.

# QOTD: protocol-based time travel for the web
- URL: https://www.lorcandempsey.net/qotd-protocol-based-time-travel-for-the-web/
- Published: 2009-11-07T22:40:55.000Z
- Updated: 2020-10-28T09:12:53.000Z
- Author: Lorcan Dempsey
- Tags: Research ∕ Learning

We are pleased that Herbert Van de Sompel will be talking about Memento, a joint project of Los Alamos National Laboratory and Old Dominion University, at OCLC later this month. We will make a webcast available; see the details [here](https://www.oclc.org/research/news/2009-11-06.htm?ref=lorcandempsey.net). If you are in Central Ohio, come by ….  
Here is a recent paper describing the work:

> The Web is ephemeral. Many resources have representa-  
> tions that change over time, and many of those represen-  
> tations are lost forever. A lucky few manage to reappear  
> as archived resources that carry their own URIs. For ex-  
> ample, some content management systems maintain version  
> pages that reflect a frozen prior state of their changing re-  
> sources. Archives recurrently crawl the web to obtain the  
> actual representation of resources, and subsequently make  
> those available via special-purpose archived resources. In  
> both cases, the archival copies have URIs that are protocol-  
> wise disconnected from the URI of the resource of which  
> they represent a prior state. Indeed, the lack of temporal  
> capabilities in the most common Web protocol, HTTP, pre-  
> vents getting to an archived resource on the basis of the  
> URI of its original. This turns accessing archived resources  
> into a signicant discovery challenge for both human and  
> software agents, which typically involves following a mul-  
> titude of links from the original to the archival resource,  
> or of searching archives for the original URI. This paper  
> proposes the protocol-based Memento solution to address  
> this problem, and describes a proof-of-concept experiment  
> that includes major servers of archival content, including  
> Wikipedia and the Internet Archive. The Memento solution  
> is based on existing HTTP capabilities applied in a novel  
> way to add the temporal dimension. The result is a frame-  
> work in which archived resources can seamlessly be reached  
> via the URI of their original: protocol-based time travel for  
> the Web. \[[Memento](https://arxiv.org/PS%5Fcache/arxiv/pdf/0911/0911.1112v2.pdf?ref=lorcandempsey.net)\]