Re: More comments on the mailserver URL scheme

Peter Deutsch (peterd@bunyip.com)
Fri, 23 Jun 1995 15:25:30 -0400


Message-Id: <9506231925.AA15612@expresso.bunyip.com>
From: Peter Deutsch <peterd@bunyip.com>
Date: Fri, 23 Jun 1995 15:25:30 -0400
In-Reply-To: Paul Hoffman's message as of Jun 23, 12:06
To: ietf-lists@proper.com (Paul Hoffman), uri@bunyip.com
Subject: Re: More comments on the mailserver URL scheme

[ someone wrote: ]

} >perhaps others have had experience with other kinds of mail servers. I
} >think it might be prudent for the URI working group to establish a
} >'maximum reasonable length for URLs' (say 512 characters) and note
} >that programs and agents that attempt to deal with URLs need to be
} >aware of the length and not exceed it. ('Those things that require
} >longer strings cannot be pointed to by URLs'). This is an issue in
} >general for URLs but is reasonably brought to mind by the mailserver
} >issue.

DANGER, WILL ROBINSON! DANGER, WILL ROBINSON!

Setting a general limit on the lengths of URLs may be a
practical necessity, but 512 bytes is way too short for
some of the applications we're already seeing. We've run
into problems with early clients that had URL buffer
lengths set too low when using URLs in which the selector
portion contains strings which are machine generated and
used internally by the server. For example, we've had
problems when the URL contains an embedded specification
for a search in the embedded WAIS search engine. In this
kind of application, the final URL gets long pretty fast
and simply saying "that's illegal" wont cut it.

} Indeed. However, I'd rather not talk about the maximum length for the first
} time in this draft. If RFC 1738 is revised, this would certainly be
} appropriate there. We could put a mention in this draft that mailserver
} URLs over 512 characters are not advised and leave it at that.

Restricting the advice to particular types of URL may
help, but I think we're into dangerous territory here.
URLs are not just for humans any more, and machine
generated and maintained ones are going to be longer than
human generated ones...

					- peterd

-- 
------------------------------------------------------------------------------

  ...there is reason to hope that the machines will use us kindly, for
  their existance will be in a great measure dependent on ours; they will
  rule us with a rod of iron, but they will not eat us...

                                               - Samuel Butler, 1872
------------------------------------------------------------------------------