D R A F T   1994-02-01

Title:	Registry for conversions between ISO/IEC 10646 and 
other coded character sets
Source:	U.S.A. (ANSI)
Status:	Contribution
Action:	For consideration by SC 2/WG 2
Distribution:	ISO/IEC JTC 1/SC 2/WG 2

In the resolutions (WG2 N949R) from WG2 Meeting 24 held in 
November, 1993, the U.S. wants to express its support for needs 
described in resolution TKS - 2.  TKS - 2 describes the need for 
an additional annex for ISO/IEC 10646-1:
The working group recognizes the need for information 
about the source of characters in UCS (such as those 
described in document N 926 item 3), and cross 
reference tables between UCS characters and characters 
in other ISO or IEC standards (list in document N 926 
item 1).  All member bodies are invited to contribute 
input towards developing an informative Annex to 
ISO/IEC 10646-1 for consideration at the next SC 2/WG 2 
meeting.
However, the U.S. asks WG2 to consider expanding the scope of the 
ideas expressed in this resolution.  
The U.S. believes that an additional need is for implementers of 
10646 to have available mappings between characters in 10646 and 
those in other coded-character sets including international and 
national standards, as well as industry coded-character-sets.  
Note that with some coded-character-sets several different 
mappings may be possible or desirable.  Therefore the need is not 
only to define the mappings but also to uniquely identify each 
mapping. Furthermore,  the U.S. believes that while including 
such information in an informative Annex to 10646-1 would be 
extremely valuable, it also would make an already long standard 
extremely burdensome to manage for ISO/IEC. In addition, it does 
not promise to be a timely mechanism for updating of this useful 
information, especially not in the case of industry coded-
character-sets. While identifying the sources of characters in 
10646 could still be done in an informative Annex, the U.S. 
recommends that the needs expressed here be implemented in a 
registry of conversions.
Enclosed is a draft NP to meet this requirement.
1.	Title
International Standard for Registry of Conversions between 
ISO/IEC 10646 and Other Coded-Character Sets
2.	Scope
The work is to produce a new international standard for a 
registry of conversions between the characters in ISO/IEC 10646 
and other coded-character-sets including international and 
national standards, and industry coded-character-sets.  
The registry will:
1.	document the conversion and
2.	provide a unique numeric and ASN.1 identifier for each 
registered conversion table
3.	Purpose and Justification
The purpose of the international standard is to define:
1.	a registration authority for a registry of conversions between 
the characters in ISO/IEC 10646 and other coded-character-sets
2.	procedures for registration
3.	criteria for registration
4.	specifics of 
a.	the information to be provided for registration
b.	the information available from the registry
The justification for this work is:
1.	Implementers of ISO/IEC 10646 require conversion information 
for interoperability.
2.	Providing an authorized ISO/IEC registry will encourage 
developers to use the conversion registry rather than 
developing their own conversions.
a.	Registration will increase interoperability.
b.	Registration will reduce duplication of effort by allowing 
a conversion to be defined once and then used by anyone.
3.	Registration is faster than standardization.
4.	For industry coded-character sets, registration of conversions 
is more appropriate than standardization.
4.	Program of Work
This project will develop a new international standard.
5.	Relevant Documents to Be Considered
ISO/IEC 10646-1:1993, Information technology – Universal 
multiple-octet coded character set (UCS) – Part 1:  Architecture 
and basic multilingual plane.
ISO 2375:1985, Data processing – Procedure for registration of 
escape sequences.
ISO/IEC 10036:1993, Information technology – Font information 
interchange – Procedure for registration of glyph and glyph 
collection identifiers.
ISO 8824:1990, Information technology – Open systems 
interconnection – Specification of abstract syntax notation one 
(ASN.1).
ISO 8825:1990, Information technology – Open systems 
interconnection – Specification of basic encoding rules for 
abstract syntax notation one (ASN.1).
ISO 9834:xxxx, Information technology – Open systems 
interconnection – Procedures for the operation of OSI 
registration authorities – general procedures.
6.	Cooperation and Liaison
Liaisons:  ISO/IEC JTC1/SC2/WG3, ISO TC46/SC4/WG1, ECMA, Unicode
7.	Preparatory Work Offered and Target Date(s)
The U.S. has prepared a draft of the proposed standard.
A CD will be ready for ballot within 6 months after approval of 
the project by JTC1.
A DIS will be ready for ballot within 6 months after resolution 
of comments on the CD.
A registration authority will be needed for this project. 
The U.S. is prepared to offer an editor for the project. 
The U.S. is prepared to offer a registration authority.
The proposed standard has no known requirements for coding.
The proposed international standard does not concern known 
patented items.
8.	Assignment of Project
It is proposed to assign this new item to JTC1/SC2/WG2.

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