13 Feb
2012
13 Feb
'12
12:47 a.m.
On Sun, Feb 12, 2012 at 11:36 PM, Randy Bush <randy@psg.com> wrote:
DNS is case-insensitive when you are talking about 7-bit ASCII < pedantry > dns itself is purely eight bit transparent. one can even have a dot as a non-separator. p.r.c could be a tld. it's strictly length/value.
That's true, but there is no standard character representation for octet values 128 - 255. If you use them in a DNS record, they are just binary values that don't refer to a specific printable symbol. Only octets in the range from 65 to 90 (uppercase) and 977 to 122 (lowercase) have a case equivalent for DNS resolution. And IDN uses 7-bit ASCII DNS records. -- -JH