Subject: Re: [dmarc-ietf] [dmarc-discuss] DMARC URI size allowance

From: Steven M Jones <[email-masked]>
Date: Wed, 14 Aug 2013 20:32:49 -0700

Adding the [dmarc-ietf] list for spec considerations. Direct follow-up 
spec discussion there; operational issues can remain with 
[dmarc-discuss]. PLEASE edit your To: and Cc: accordingly.

Originating message on [dmarc-discuss] from Tomki Camp queried how many 
implementations obeyed the optional report size limitations described in 
section 5.1 ...

  On 08/14/2013 05:21 PM, Franck Martin wrote:
> On Aug 14, 2013, at 5:07 PM, Matt Simerson <[email-masked]> wrote:
>> I just iterate over the URI list and send the report to each one, skipping over any where the message size exceeds the published limit.
> But this is not the intent, you are supposed to cut the report in smaller chunks and send them... (just saying ;)

Can you cite the section(s) for that behavior, Franck?

Matt, if no reports can be sent based on size limits, do you then send a 
"reports too big" notice to all the mailto: URIs per section 11.2.4?

Section 11.2 indicates that any reporting URI with a size limit lower 
than the current report size should be skipped, with an exception that 
if no URIs qualify to receive a report, Mail Receivers should follow 
section 11.2.4 to send a "report too big" notice.

Section 11.2.1 for the Email transport notes the possibility of a report 
larger than can be accepted by a mailto: URI and refers to section 
11.2.4. Section 11.2.2 for the HTTP transport does not make a specific 
reference to the size limitation; neither does section 11.2.3 which 
notes the opportunity to add additional transports in future. I'd 
recommend that it just be made clear that the handling specified in 
section 11.2 applies across all transports.

Pursuant to the original question though, has anybody received an error 
report as described in section 11.2.4 in the wild? I'm curious because 
there's a note in the spec that a more rigorous definition will be added 
based on operational experience...  I'll go bodge something to generate 
some, but organic examples would probably be better if we've got any.

Thanks,
--Steve.