Rob Seaman wrote: >Any implementation should support the entire table of leap seconds.
I agree. I'd arrange the DNS mechanism such that the queried domain name encodes the month, and the resource record just represents the TAI-UTC difference that applies that month. Leap events are implied by the difference changing between months. NXDOMAIN for a particular month means that the TAI-UTC difference for that month hasn't been decided yet. TTLs for filled months can be arbitrarily large. The effective TTL for an NXDOMAIN response mustn't exceed a few months, and may be usefully manipulated in anticipation of Bulletin C's release. $origin tai-utc.example. $ttl 100000000 @ in soa . . ( 2015013100 100000 10000 1000000 100000 ) 1972-01 txt "10" 1972-02 txt "10" 1972-03 txt "10" 1972-04 txt "10" 1972-05 txt "10" 1972-06 txt "10" 1972-07 txt "11" 1972-08 txt "11" ... 2015-05 txt "35" 2015-06 txt "35" 2015-07 txt "36" 2015-08 txt "36" 2015-09 txt "36" 2015-10 txt "36" 2015-11 txt "36" 2015-12 txt "36" The TAI-UTC difference may also be encoded in A and AAAA records to support lookup via gethostbyname(). -zefram _______________________________________________ LEAPSECS mailing list LEAPSECS@leapsecond.com https://pairlist6.pair.net/mailman/listinfo/leapsecs