Hi Jim,
I'm lost with these DNS considerations. Your option 3 is apparently
the "CSV method" (or rather the CSV method was an elaborated variant
of a naive tree walk, for starters it never hit the root servers)
Anything using wildcards where they're not already used today could
also run into trouble. If folks like it anyway I hope they've read
I-D.iab-dns-synthesis-concerns-00
Frank
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