[Cbor] Multiple questions with CBOR for DNS

[Martine Sophie Lenders <[e-mail]>]

Hi all,

Esko talked yesterday about the potential requirements of having two 
questions in a DNS message. I think this could be achieved with a small 
extension to the existing definition that makes the question section an 
alternating list of names an type-specs (each pair of those being one 
question):

     question-section = [question+]
     question = (
       name: domain-name,
       ? type-spec,
     )

The only caveat I see is, that if we go with the componified domain name 
definition I presented yesterday, that at least a record type needs to 
be provided when more than one question is used. Otherwise, the 
compontents of names of different questions will become hard to keep 
apart by a parser.

Alternatively, we can go for a list of list in the question (each of the 
inner lists being a question). This has two caveats, however. (1) The 
question section will be harder to distinguish from the other sections 
in the response (given that it is optional, this is important). (2) We 
add at least 1 extra byte for the very rare (and by most resolvers not 
accepted) case that someone wants to have more than one questions.

Best
Martine