spf-discuss
[Top] [All Lists]

Re: Re: [IETF] Allocation of the new RR type for SPF

2004-11-23 17:56:15
On Tue, Nov 23, 2004 at 07:26:30PM -0500, terry(_at_)ashtonwoodshomes(_dot_)com 
wrote:
wayne wrote:
Personally, I don't think that exclusively using a DNS RR in
the spec that won't exist on most people's name servers for
many months or years is very productive.

And you are certainly correct for the short term, and probably correct for at 
least a couple years
to come.

What would be a realistic, conversative, number ?

If we want to get rid of TXT records there MUST be a MUST NOT USE
clause in the RFC.  For instance (example numbers, change to fit):

The following is surrounded by the necessary "spf is optional, if
you are going to implement it then these are the requirements"

 ... "SPF is currently (2005) deployed using the TXT record.  A specific
      resource record for SPF has been assigned (see ...) and people are
      encouraged to start using this new record ASAP.

      However, for a smooth transition from TXT to the SPF RR, both need
      to coexist for a while.  The following time table MUST be used:

      Years 2005 upto and including 2007:
      Senders
       - MUST provide a TXT record
       - SHOULD provide an SPF record
       - When present, the SPF record MUST provide the same information
      Receivers
       - MAY query an SPF record (and are encouraged to do so)
       - MUST use it if found
       - MUST NOT query nor use a TXT record if an SPF record is found
       - MUST query and use a TXT record if an SPF record cannot be found

      Year 2008 (transition period):
      Sites
       - MUST provide a TXT record 
       - MUST provide an SPF record
       - the TXT record MUST provide the same information
      Receivers
       - SHOULD query an SPF record
       - MUST use it if found
       - MUST NOT query nor use a TXT record if an SPF record is found
       - MUST query and use a TXT record if an SPF record cannot be found

      Year 2009 and further
      Sites
       - MUST NOT provide a TXT record
       - MUST provide an SPF record
      Receivers
       - MUST query and use an SPF record
       - MUST NOT query a TXT record
"...


cheers,
Alex