Re: Microsoft takes over British Telecom

On 23/10/2011 17:09, Steve Atkins wrote:
> On Oct 23, 2011, at 7:39 AM, Alessandro Vesely wrote:
>
>> On 21/Oct/11 19:07, Steve Atkins wrote:
>>> The bigger issue is that you shouldn't care about SPF failing. An SPF pass
>>> provides somewhat useful data, an SPF fail means absolutely nothing.
>> Wasn't it supposed to mean "reject"?  IIRC, that was the difference
>> between setting -all (as irtf.org does) rather than ~all or ?all.
> That's what it's proponents used to claim, yes. But it's unfixably broken for
> that purpose. The only reason you don't see serious mail problems for
> anyone unwise enough to use -all is that almost nobody pays much attention
> to SPF for rejecting email.
>
How is it 'unfixably' broken? Just interested.

it seems to me that the only reason it's 'unfixably broken' is that 
people are using it without really understanding what it's doing. If all 
MTAs rejected all mail that failed SPF checks, then they'd soon get the 
problems fixed. Remote users having to relay via a specified submission 
server is a trivial problem to fix (AFAICS), and incorrectly specified 
SPF records (as in the BT/MS case) deserve to cause messages to be 
blocked (IMHO)

(SPF is certainly not that useful as an 'anti-spam' mechanism, but it 
seems to have the potential to work reasonably well as an anti-spoofing 
mechanism, which makes it considerably harder for many spammers)