Re: Intent to revive "expires" header from draft-ietf-mailext-new-fields-15

Michael Welzl wrote:
> Hi all,
> 
> 
> On Sun, 2008-07-27 at 13:35 -0400, Hector Santos wrote:
> 
> [snip]
> 
> 
>> IMO, if we can't make this new proposal of a Sender define "expires" 
>> header consistent with already existing standard practices, then IMO, 
>> it should be call something else.
> 
> To repeat the nice definition that Keith gave us, and which most
> of us seem to like:

But is not realistic.

What is more realistic is the original intent of the I-D you 
referenced in which you tried to revive the "Expires" header:

    http://tools.ietf.org/html/draft-ietf-mailext-new-fields-15

where it defines Expires as:

    4. Expires:

    Syntax: Expires-field = "Expires:" CFWS date-time [CFWS] CRLF

    The Expires header indicates a date-time, at which this
    message expires. The field can be used both to limit and to
    extend the life of a message. User agents and servers which
    employ automatic purging of old messages MAY let this field
    influence the purging process. There is no requirement that a
    user agent must suppress expired messages or make them
    inaccessible to their owners.

It is quite clear of the intent and the engineerings insights for 
forth in the Expires header:

    ... servers which employ automatic purging of old messages
    MAY let this field influence the purging process.

You can't ignore this.

-- 
HLS