spf-discuss
[Top] [All Lists]

Re: considering XML

2004-01-21 23:54:05
On Wed, Jan 21, 2004 at 02:50:24PM -0500, Meng Weng Wong wrote:

| On Wed, Jan 21, 2004 at 01:17:42PM -0600, wayne wrote:
| | In <20040121185921(_dot_)GD6875(_at_)dumbo(_dot_)pobox(_dot_)com> Meng Weng 
Wong <mengwong(_at_)dumbo(_dot_)pobox(_dot_)com> writes:
| | 
| | > In theory, extensibility will be built in [if we use XML].
| | 
| | I guess I disagree with this.  We *could* have allowed unrecognized
| | mechanisms to be ignored in SPF.  I think we made the right decision
| | to not silently ignore typos.
| | 
| | I do not understand XML that well, but I can't see how new mechanisms
| | can be created and understood by those systems that need to check SPF
| | records.
| 
| Well, the idea is that if a sender domain wants to define a new
| mechanism, it can change the xmlns attribute to point to its DTD and
| people out there can subscribe to it.  Is that the idea?

But how do you get that new mechanism's implementation semantics/logic to
execute in all MTAs that access that SPF data?  Would we have to also send
along some Java bytecode?  I sure as hell hope not.

Extensions should fall into two categories:  1: user defined, and 2: well
studied, vetted, and commonly agreed on.  Those in number 2 don't need XML
since they don't depend on end user extensibility; they can be added to the
standard if it is decided that it is good.  I also think the number of
mechanisms needs to be under control.  But those in number 1 can still be
done by anyone who wants to implement any oddball logic by using exists
with a macro formatted to send all the necessary data in the query, and
let a specially coded/hacked DNS server figure it out and answer back.

-- 
-----------------------------------------------------------------------------
| Phil Howard KA9WGN       | http://linuxhomepage.com/      http://ham.org/ |
| (first name) at ipal.net | http://phil.ipal.org/   http://ka9wgn.ham.org/ |
-----------------------------------------------------------------------------

-------
Sender Permitted From: http://spf.pobox.com/
Archives at http://archives.listbox.com/spf-discuss/current/
Latest draft at http://spf.pobox.com/draft-mengwong-spf-02.9.4.txt
To unsubscribe, change your address, or temporarily deactivate your 
subscription, 
please go to 
http://v2.listbox.com/member/?listname(_at_)©#«Mo\¯HÝÜîU;±¤Ö¤Íµø?¡


<Prev in Thread] Current Thread [Next in Thread>