Integration of BIDI into the protocol

James Mitchell james.mitchell at
Tue Sep 1 03:33:56 CEST 2009

> > As a registry, should I allow registration of the name 123abc.RTL?
> >
> My recommendation is that you should (as a registry) establish policy
> that says "it is not allowed". The protocol does not require you to do so.
> > As an application, should I lookup the name 123abc.RTL?
> >
> The protocol does not say that you can't. For the obvious reasons, I
> think it's a legitimate implementor decision to decide not to.

I was of the assumption that the lookup protocol was no more restrictive than the registration protocol.

I propose that one of the following changes is made to draft-ietf-idnabis-protocol-14.  The first to clarify that registries are expected to establish policy for this specific issue (or potentially be suprised if they do not), and the second to prevent such labels entirely.  I am leaning towards the latter only because the protocol states such names SHOULD be rejected in lookup.  Labels Containing Characters Written Right to Left

   If the proposed label contains any characters that are written from
   right to left it MUST meet the BIDI criteria [IDNA2008-BIDI].

   Note that a label containing no characters written from right to left
   may fail to meet the BIDI criteria when in a name having at least one
   label containing right to left characters.  It is expected that
   registries establish policy for the registration of such labels.


   If the proposed label, or the name in which it belongs, contains any
   characters that are written from right to left then the proposed label
   MUST meet the BIDI criteria.

I welcome any updates to the wording of these changes.


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