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Re: [idn] length restrictions on IDN label
Soobok Lee <email@example.com> wrote:
> If UTF8-encoded, that valid 8bit label will exceed 63 octets limits
> (up to 168 octets or more)
> which is imposed by RFC1035 even upon non-ASCII 8bit labels .
Yes, but labels in DNS containing octets >= 128 are not
internationalized labels, because internationalized labels use only
octets <= 127 in DNS. Labels in DNS containing octets >= 128 are
mysterious creatures that have no standard interpretation as text
(because ASCII is the only text encoding used by the DNS standard).
> IDNA section 6.3 does not rule out that utf8 encoded labels may be
> used in DNS wire protocols in the future.
In which case the specification of those future wire protocols will need
to deal with the fact that UTF-8 forms of internationalized labels can
have more than 63 octets. (255 is an upper bound, though not the least