spf-discuss
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Re: Forking SPF into The New SPF and SPF1

2004-06-07 13:09:27
On Mon, 7 Jun 2004, Julian Mehnle wrote:

I'm thinking about forking SPF into "The New SPF" and a non-XML "SPF1"
variant, i.e. keep The Old SPF going separately and independently from The
New SPF.

Who's with me?

A "fork" implies that one branch of the fork plans to ignore the other branch
completely.  I think what is needed is not a "fork".  In fact, I suggest we
*not* call it a fork.  I really like the proposed term "layers".  We need to
keep layer 1 (SPF1 - before DATA - RFC 2821).  Layer 2 (XML/CID - after DATA -
RFC2822) can proceed independently.  They are not mutually exclusive.  There is
value to using either or both.

There are some proposed extensions to layer 1 which basically copy some data
from layer 2 to layer 1 and verify it later by comparing to the
actual RFC 2822 header.  This may allow more messages to be rejected
in layer 1 (if the copied data is a lie, it will be rejected in layer 2).
These extensions are worth considering.  However, trying to directly combine
layer 1 with layer 2 will kill both.

It will be much easier to sell supporting both SPF and XML syntax if
each syntax is confined to its own layer.  Layer 1 needs the lightweight
SPF syntax.  Layer 2 benefits from the flexibility of XML - especially
the ability to extract only the subtrees supported by local software.
Users and vendors would not be required to implement both.  If they
only want to check layer 1 authentication, they need only parse SPF1.

If they want to authenticate RFC 2822 headers, (other than the
ones copied to layer 1 in a future revision of SPF1) and/or message body
and signatures, they will need to parse XML.

-- 
              Stuart D. Gathman <stuart(_at_)bmsi(_dot_)com>
    Business Management Systems Inc.  Phone: 703 591-0911 Fax: 703 591-6154
"Confutatis maledictis, flamis acribus addictis" - background song for
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