Subject: Re: CCL:WWW developments

From: "David E. Bernholdt" <[email-masked]>
Date: Tue, 09 Apr 96 10:13:34 -0400

> but what we really want to know is whether the CONTENT
> of a requested applet is identical to the content of one in cache,
> regardless of the name (URL) of the applet.  To do an exhaustive
> comparison, we'd have to get the remote applet anyway, so this is
> not a viable alternative.  What I'm suggesting is some unique
> way of identifying an applet, independent of its URL.

Actually, this is not technically hard, and is related to issues of
code/data integrity and security which are becoming increasingly
important concerns on "the net". (see also encryption, digital
signatures, PGP, ...)

In this case, you could apply a secure one-way hash (aka digital
signature, such as MD5) to the data and compare the signatures.  The
signature is a short (16 or 32 digit?) hexadecimal number, so it is
quick to transmit and MD5 is not too hard to compute.  I believe
chance of identical MD5 signatures arising from different inputs is
2^-64 (5e-20), which ought to satisfy most uses.

I'm not aware of any browsers which do this now, but its probably
coming.
--
David E. Bernholdt                      | Email:  [email-masked]
Northeast Parallel Architectures Center | Phone:  +1 315 443 3857
111 College Place, Syracuse University  | Fax:    +1 315 443 1973
Syracuse, NY 13244-4100                 | URL:    http://www.npac.syr.edu