I have two CAA questions from our technical group.  I am posting here to see 
what others think.  Do we need to make any changes to BR 3.2.2.8 (created under 
Ballot 187)?  Thanks for any feedback.

QUESTION 1

Subject: CAA ballot and handling of REFUSED status response from authoritative 
name servers

Suppose we have a domain "demo-k2k.com" that have NS records pointing to 
"ns1.demo-k2k.com" and ns2.demo-k2k.com as the authoritative name servers. When 
we query "ns1.demo-k2k.com" for the CAA records for "demo-k2k.com", it returns 
a status of REFUSED. This may be due to a misconfiguration or the restricted 
access may be intentional.

We now have a scenario where the record lookup for "demo-k2k.com" has failed.

According to ballot 187, CAs are permitted to treat a record lookup failure as 
permission to issue if:


1.       the failure is outside the CA's infrastructure;

2.       the lookup has been retried at least once; and

3.       the domain's zone does not have a DNSSEC validation chain to the ICANN 
root.

Condition #1 is satisfied, the failure is outside the CA's infrastructure.
We can satisfy Condition #2 by retrying - we get the same REFUSED status in the 
response.

Because of the "and" clause in above ballot excerpt, we must also satisfy 
condition #3 if we want to treat the lookup failure as permission to issue.
We cannot, however, determine whether the "domain's zone does not have a DNSSEC 
validation chain to the ICANN root" because the domain's zone authoritative 
name servers are refusing to answer our DNS queries.

This scenario is encountered often enough in the real world that it would 
prevent many certificates from being issued if ballot 187 is followed.

One potential solution is to allow CA's to treat REFUSED status responses from 
authoritative name servers as permission to issue.

QUESTION 2

Subject: Handling CAA record with single character in it

We have found a CAA record that consists only of a semi-colon ";"  So the field 
is not empty, but also does not designate any known CAs.

Our team assumes this effectively blocks all CAs from issuing to this domain.  
Do others agree?

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