Consensus Call on Latin Sharp S and Greek Final Sigma

Vaggelis Segredakis segred at
Mon Nov 30 16:02:30 CET 2009

Dear Vint,

If the question you raised is a step to eliminate these two characters then
my answer is NO;

(1) Both characters should be PVALID

However, please keep in mind that I do not regard the solution of the IDNA
protocol in general as optimal solution (please take a look at my
presentation in the last IGF meeting in Egypt
f). This protocol presents lots of shortcomings for the Greek language and
actually requests from the end-user to adapt to it instead of the protocol
adapting to the languages.

As we move forward with IDNA2008 I would welcome very much a request from
this WG to the IETF to introduce a xNAME command in the DNS that will allow
whole domain name trees to equal each other (one level above DNAME) since
Greek registrants will have to have lots of domain names pointing one to the
other just to receive emails properly. 

If this wouldn't be a choice, a new protocol that would take in account all
these issues and start from scratch, maybe with character formatting instead
of PUNYCODE translations and mappings would be a nicer solution than a patch
of the IDNA which carries skeletons of the past. However, this very last
paragraph is my personal wish-list and not a formal position.

Kind Regards,

Vaggelis Segredakis
Administrator of the .GR Top Level Domain
Institute of Computer Science
Foundation for Research and Technology - Hellas
Tel. +30-281-0391450
Fax +30-281-0391451
Email segred at

Message: 2
Date: Sat, 28 Nov 2009 18:28:22 -0500
From: Vint Cerf <vint at>
Subject: Consensus Call on Latin Sharp S and Greek Final Sigma
To: idna-update at	
Cc: lisa Dusseault <lisa.dusseault at>
Message-ID: <3FCFF859-FEB2-4586-98EA-401F0853F78E at>
Content-Type: text/plain; charset=US-ASCII; format=flowed; delsp=yes

In consultation with the area director, issues were raised concerning the
consensus on the use of Latin small letter sharp S and Greek small final
sigma as PVALID in IDNA2008.

I have copied the working group on a request for opinion from the Unicode
Technical Committee.

By this message, I request a response from the Working Group on the

Should Latin Small Letter Sharp S and Greek Small Letter Final Sigma be
PVALID in IDNA2008 or not:

Please Respond by choosing among the following:

(1) Both characters should be PVALID
(2) Both characters should be DISALLOWED
(3) Only Latin Small Letter Sharp S should be PVALID
(4) Only Greek Small Letter Final Sigma should be PVALID

Choices (3) and (4) create additional complexity in dealing with
IDNA2003 and IDNA2008 disparities

During the Last Call, a number of objections were raised with regard to
choice (1) and this led the Area Director to question the rough consensus
that the WG submission to IESG claimed.

It will be much appreciated if all working group members would respond by
December 8.


vint cerf

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