Re: A.10.1

Well, according to the specifications there isn't. The mechanism in teh
Recommendations is to do exactly as Nir suggests. What is often used is
the pseudo-HTTP command refresh, which has been implemented by a number of
browsers directly, and does allow for a timed redirect. Perhaps we should
recommend not using the timed redirect more strongly.

Charles

On Fri, 29 Jan 1999, Nir Dagan wrote:

  With all due respect, there is no such thing as 
  "instant rediction" or "timed response".
  
  The optimal way to redirect the user to a new page
  when a URL is moved permanently is by returning 
  the status code 301 as per HTTP/1.1 (some older servers 
  like CERN's can't do that but can give a 302 status code which is 
  almost as good)
  
  Whether this is instant or not is up to the user agent.
  For example the W3C validator recognizes the HTTP status 
  codes 301 and 302 but informes the user of the new location 
  rather than validating instantly the document in the new location.
  
  I would recommend using the appropriate redirect HTTP status,
  and if this is impossible, just to place a page with a normal link 
  to the new URL, indicating that this technique is suboptimal as 
  link checker programs and indexing robots are less likely to update 
  their records timely if at all. For the sake of completeness I would mention
  the the META refresh thing is non-standard (without a disscussion)
  and that it is not supported by many agents.
  
  Regards,
  
  Nir Dagan
  Assistant Professor of Economics
  Universidad Pompeu Fabra
  Ramon Trias Fargas 25
  08005 Barcelona
  Spain
  
  http://www.nirdagan.com
  mailto:nir@nirdagan.com
  
  "There is nothing quite so practical as a good theory." 
  -- A. Einstein
  

--Charles McCathieNevile            mailto:charles@w3.org
phone: +1 617 258 0992   http://purl.oclc.org/net/charles
W3C Web Accessibility Initiative    http://www.w3.org/WAI
MIT/LCS  -  545 Technology sq., Cambridge MA, 02139,  USA

Received on Thursday, 28 January 1999 12:50:34 UTC