Re: [DNSOP] draft-lewis-domain-names-00.txt

[Alec Muffett <[e-mail]>]

> On Sep 18, 2015, at 14:16, George Michaelson <[e-mail]> wrote:
> 
> My private comment bears repeating in public.
> 
> DOMAIN names is about the property of domains. Domains are encompassing, set-theory/venn-diagram style. A domain and a prefix are analogous concepts. One is expressed syntactically somehow, the other is a mathematical property of bounding in a number field but they have the same basic behaviour.
> 
> the UK domain order in coloured book mails obeyed this property: it just used reverse semantics to the ARPA model.
> 
> XXXXXXXX.onion is *not* a domain name inside the .onion part: as I understand it, the value is a hash, or other function which has no nesting properties expressed syntactically.

Hi, my name's Alec, I work for Facebook and lead the engineering team for Facebook over Tor.

You are certainly correct that the label immediately left of ".onion" is a hash, and functions not unlike a layer-3 address; however, there may be other labels leftwards of the hash, under (to some extent) other administrative control.

The canonical example of this would be: www.facebookcorewwwi.onion <http://www.facebookcorewwwi.onion/> versus m.facebookcorewwwwi.onion versus… well, anything.you.like.sixteencharshash.onion.

With onion addressing it's all a matter of whether the layer 7 protocol honours the symbolic name that it has been given (eg: www.facebookcorewwwi.onion <http://www.facebookcorewwwi.onion/>) and passes it to the server via metadata (eg: HTTP "Host:" header) rather than a delegated and differentiated address lookup.

I feel this may need clarification in your section on Tor addressing.  Perhaps it's not **really** domain-naming, but it **looks** much more like it.

Also, there is some information which requires correction:

According to an email message, ".onion" names may (in the future)
exceed the length limits of a label imposed on DNS domain names,
reaching 64, 80, or more bytes. [DNSOP1]

Per this e-mail:

https://www.ietf.org/mail-archive/web/ietf/current/msg94362.html <https://www.ietf.org/mail-archive/web/ietf/current/msg94362.html>

...from Nick Mathewson at Tor, he says:
So it's IMO fine to say ".onion addresses are case-insensitive and
will comply with existing DNS limitations for label lengths (63) and
maximum fqdn lengths (253ish)".
Which contradicts draft-lewis-domain-names-00

Also, my name's not "Alex" :-)

    - alec