number of characters in a domain?

Sun Jul 24 05:03:20 UTC 2016

The number of wire octets is <= 255.
The number of presentation characters <= 1008 (63*4*3 + 62*4 + 4)

In message <5793C61B.4080107 at dougbarton.us>, Doug Barton writes:
> On 07/23/2016 07:07 AM, Matthew Pounsett wrote:
> > On 23 July 2016 at 14:31, Ryan Finnesey <ryan at finnesey.com> wrote:
> >
> >> I was hoping someone can help me confirm my research.  I am correct that
> >> domains are now limited to 67 characters in length including the extension?
> >>
> >
> > 63 octets per label (the bits between the period separators) , 255 octets
> > per domain name. In ascii octets and characters are interchangeable, but as
> > Stephan noted, it gets slightly more complicated for IDN.
> 
> Not really ... the 1035 limits apply to the A-label
> 
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Mark Andrews, ISC
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