Re: length restrictions on IDN label

> If this limit is a new and independent from the underlying "native" DNS,
> what is the reason for it?  If it is not independent, why duplicate it?

It isn't independent since the limit derives from the label length limit
in the DNS protocol, but the limit is also a function of the amount
of compression that punycode performs.

The fact that punycode will never generate a string with less
number of code points than the number of code points in the input
is far from obvious, hence it makes sense in my mind to state this limit.

  Erik