PRECIS Framework: Preparation, Enforcement, and Comparison of Internationalized Strings in Application Protocols
draft-ietf-precis-framework-19

• Status
• IESG evaluation record
• IESG writeups
• Email expansions
• History

• Versions
• 01
• 02
• 03
• 04
• 05
• 06
• 07
• 08
• 09
• 10
• 11
• 12
• 13
• 14
• 15
• 16
• 17
• 18
• 19
• 20
• 21
• 22
• 23

PRECIS                                                    P. Saint-Andre
Internet-Draft                                                      &yet
Obsoletes: 3454 (if approved)                                M. Blanchet
Intended status: Standards Track                                Viagenie
Expires: April 26, 2015                                 October 23, 2014

     PRECIS Framework: Preparation, Enforcement, and Comparison of
           Internationalized Strings in Application Protocols
                     draft-ietf-precis-framework-19

Abstract

   Application protocols using Unicode characters in protocol strings
   need to properly handle such strings in order to enforce
   internationalization rules for strings placed in various protocol
   slots (such as addresses and identifiers) and to perform valid
   comparison operations (e.g., for purposes of authentication or
   authorization).  This document defines a framework enabling
   application protocols to perform the preparation, enforcements, and
   comparison of internationalized strings ("PRECIS") in a way that
   depends on the properties of Unicode characters and thus is agile
   with respect to versions of Unicode.  As a result, this framework
   provides a more sustainable approach to the handling of
   internationalized strings than the previous framework, known as
   Stringprep (RFC 3454).  This document obsoletes RFC 3454.

Status of This Memo

   This Internet-Draft is submitted in full conformance with the
   provisions of BCP 78 and BCP 79.

   Internet-Drafts are working documents of the Internet Engineering
   Task Force (IETF).  Note that other groups may also distribute
   working documents as Internet-Drafts.  The list of current Internet-
   Drafts is at http://datatracker.ietf.org/drafts/current/.

   Internet-Drafts are draft documents valid for a maximum of six months
   and may be updated, replaced, or obsoleted by other documents at any
   time.  It is inappropriate to use Internet-Drafts as reference
   material or to cite them other than as "work in progress."

   This Internet-Draft will expire on April 26, 2015.

Saint-Andre & Blanchet   Expires April 26, 2015                 [Page 1]
Internet-Draft              PRECIS Framework                October 2014

Copyright Notice

   Copyright (c) 2014 IETF Trust and the persons identified as the
   document authors.  All rights reserved.

   This document is subject to BCP 78 and the IETF Trust's Legal
   Provisions Relating to IETF Documents
   (http://trustee.ietf.org/license-info) in effect on the date of
   publication of this document.  Please review these documents
   carefully, as they describe your rights and restrictions with respect
   to this document.  Code Components extracted from this document must
   include Simplified BSD License text as described in Section 4.e of
   the Trust Legal Provisions and are provided without warranty as
   described in the Simplified BSD License.

Table of Contents

   1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   3
   2.  Terminology . . . . . . . . . . . . . . . . . . . . . . . . .   6
   3.  Preparation, Enforcement, and Comparison  . . . . . . . . . .   6
   4.  String Classes  . . . . . . . . . . . . . . . . . . . . . . .   7
     4.1.  Overview  . . . . . . . . . . . . . . . . . . . . . . . .   7
     4.2.  IdentifierClass . . . . . . . . . . . . . . . . . . . . .   8
       4.2.1.  Valid . . . . . . . . . . . . . . . . . . . . . . . .   9
       4.2.2.  Contextual Rule Required  . . . . . . . . . . . . . .   9
       4.2.3.  Disallowed  . . . . . . . . . . . . . . . . . . . . .   9
       4.2.4.  Unassigned  . . . . . . . . . . . . . . . . . . . . .  10
       4.2.5.  Examples  . . . . . . . . . . . . . . . . . . . . . .  10
     4.3.  FreeformClass . . . . . . . . . . . . . . . . . . . . . .  10
       4.3.1.  Valid . . . . . . . . . . . . . . . . . . . . . . . .  10
       4.3.2.  Contextual Rule Required  . . . . . . . . . . . . . .  11
       4.3.3.  Disallowed  . . . . . . . . . . . . . . . . . . . . .  11
       4.3.4.  Unassigned  . . . . . . . . . . . . . . . . . . . . .  11
       4.3.5.  Examples  . . . . . . . . . . . . . . . . . . . . . .  12
   5.  Profiles  . . . . . . . . . . . . . . . . . . . . . . . . . .  12
     5.1.  Profiles Must Not Be Multiplied Beyond Necessity  . . . .  12
     5.2.  Rules . . . . . . . . . . . . . . . . . . . . . . . . . .  13
       5.2.1.  Width Mapping Rule  . . . . . . . . . . . . . . . . .  13
       5.2.2.  Additional Mapping Rule . . . . . . . . . . . . . . .  13
       5.2.3.  Case Mapping Rule . . . . . . . . . . . . . . . . . .  14
       5.2.4.  Normalization Rule  . . . . . . . . . . . . . . . . .  14
       5.2.5.  Exclusion Rule  . . . . . . . . . . . . . . . . . . .  14
       5.2.6.  Directionality Rule . . . . . . . . . . . . . . . . .  15
     5.3.  Building Application-Layer Constructs . . . . . . . . . .  15
     5.4.  A Note about Spaces . . . . . . . . . . . . . . . . . . .  16