Subject: Caching/Prefetching

From: Michael Angerman <[email-masked]>
Date: Tue, 10 Apr 2001 14:26:38 +0200 (MET DST)

Hi there,

I am currently investigating some questions in the area of caching,
or more accurately pre-fetching of objects (e.g. html, images,
applications). At the moment I am making some experiments with
a forecasting proxy based on path profiling and markov chains.
As I feel I should consider "real-world" limitations and 
existing protocols very early, I try to find out the current status of this
topic within the IETF.
 
ICP (RFC 2186) and HTCP (RFC 2756) are about caching.
I couldn't find any active working group investigating
prefetching and its mechanisms an the IETF website.

If anybody is interested in this topic or would share some
experience and knowledge I would be very happy.

Best regards,

Michael 
 
--
Dipl.-Ing. Michael Angermann

German Aerospace Center
Site Oberpfaffenhofen
Institute for Communications Technology
P.O. Box 1116
D-82230 Wessling

Tel.: +49-8153-28-2893
Fax.: +49-8153-28-1442

---

From: Mark Nottingham <[email-masked]>
Date: Tue, 10 Apr 2001 11:32:50 -0700

Michael,

Prefetching is isn't something that's standardized; there's a coherence
model in the HTTP, but it only specifies server- and client-directed
cache freshness, while leaving the determiniation of heuristic
freshness up to implementations. 

Prefetching might be thought of as a further, somewhat orthoganal,
optimisation over heuristic freshness algorithms. As such, there
isn't any work surrounding it in the IETF (or other standards bodies,
as far as I'm aware), and there isn't likely to be, IMHO. 

OTOH, I imagine that a patent search would show some results, as at
least one vendor claims to do it well. Additionally, prefetching has
been the topic of many a research paper, much as optimal Web cache
replacement algorithms have been. 

The best place to start for more information would probably be:
  http://www.cs.wpi.edu/~webbib/

-- 
Mark Nottingham, Research Scientist
Akamai Technologies (San Mateo, CA USA)