Re: MHTML/HTTP 1.1 Conflicts

>  From: Scott Lawrence <>
>  Date: Fri, 23 Jan 1998 11:51:13 -0500 (EST)
>  To: Jim Gettys <>
>  Cc: Nick Shelness <>,
>          IETF working group on HTML in e-mail <mhtml@SEGATE.SUNET.SE>,
>, Nick_Shelness/SSW/
>  Subject: Re: MHTML/HTTP 1.1 Conflicts
>  On Fri, 23 Jan 1998, Jim Gettys wrote:
>  > 1. Content-Base
>  > 
>  > Note that Content-Base is being removed from the HTTP/1.1 specification,
>  > per the minutes of our last editorial meeting.  I think that closes
>  > out any conflict between the specifications for Content-Base.
>    Actually Jim, I think that it creates one - MHTML agents will expect it
>    to be honored, while HTTP agents will ignore it.  Another sentence or
>    two in the interoperation notes...

The reality today is that Content-Base is ignored in HTTP (wasn't in HTTP/1.0, 
and isn't honored by any current browser of note).    Without a robust 
extension mechanism, we didn't see how to get it introduced reliably into 
the Web.

And as you pass off the message to an MHTML agent, the MHTML agent can do 
what it likes with Content-Base.

At most, Content-Base is providing additional information that can be
passed to external viewers.  This was the reason Roy gave as to why
he hadn't said "MUST" in the first place when drafting Content-Base.
It was a statement of fact, as opposed to something required to make
the protocol work.

There really isn't anything at the protocol level that makes the
protocol depend on it; it is additional meta-data for the content type
rederer to use.

Removing Content-Base does require referencing 2068, if only to say that 
it isn't in the draft standard.  It may be that we should also call
out a reference to the MHTML spec that it uses it in interpreting content.

				- Jim

Jim Gettys
Industry Standards and Consortia
Digital Equipment Corporation
Visting Scientist, World Wide Web Consortium, M.I.T.,

Received on Friday, 23 January 1998 09:46:16 UTC