Message ORGanization Working Group A. Melnikov Internet-Draft D. Cridland Intended status: Standards Track Isode Limited Expires: January 14, 2010 July 13, 2009 IMAP4 Keyword Registry draft-melnikov-imap-keywords-04 Status of this Memo This Internet-Draft is submitted to IETF in full conformance with the provisions of BCP 78 and BCP 79. Internet-Drafts are working documents of the Internet Engineering Task Force (IETF), its areas, and its working groups. Note that other groups may also distribute working documents as Internet- Drafts. 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." The list of current Internet-Drafts can be accessed at http://www.ietf.org/ietf/1id-abstracts.txt. The list of Internet-Draft Shadow Directories can be accessed at http://www.ietf.org/shadow.html. This Internet-Draft will expire on January 14, 2010. Copyright Notice Copyright (c) 2009 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 in effect on the date of publication of this document (http://trustee.ietf.org/license-info). Please review these documents carefully, as they describe your rights and restrictions with respect to this document. Abstract The aim of this document is to establishe a new IANA registry for IMAP keywords and to define a procedure for keyword registration, in order to improve interoperability between different IMAP clients. Melnikov & Cridland Expires January 14, 2010 [Page 1] Internet-Draft IMAP4 Keyword Registry July 2009 Note A revised version of this draft document will be submitted to the RFC editor as a Proposed Standard for the Internet Community. Discussion and suggestions for improvement are requested, and should be sent to morg@ietf.org. Table of Contents 1. Conventions used in this document . . . . . . . . . . . . . . 3 2. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3 3. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 3 3.1. Comments on IMAP Keywords' Registrations . . . . . . . . . . 5 3.2. Change Control . . . . . . . . . . . . . . . . . . . . . . . 5 3.3. Initial registrations . . . . . . . . . . . . . . . . . . . . 5 4. Security Considerations . . . . . . . . . . . . . . . . . . . 7 5. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 7 6. References . . . . . . . . . . . . . . . . . . . . . . . . . 7 6.1. Normative References . . . . . . . . . . . . . . . . . . . . 7 6.2. Informative References . . . . . . . . . . . . . . . . . . . 7 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . 8 Melnikov & Cridland Expires January 14, 2010 [Page 2] Internet-Draft IMAP4 Keyword Registry July 2009 1. Conventions used in this document The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in RFC 2119 [Kwds]. 2. Introduction IMAP Keywords [RFC3501] are boolean named flags that can be used by clients to annotate messages in an IMAP mailbox. Although support for IMAP keywords is an optional feature of IMAP, the majority of IMAP servers allow for storing of arbitrary keywords. Many mainstream IMAP clients support some specific keywords, and some can manage arbitrary IMAP keywords. Over years some IMAP keywords have become de-facto standard, with some specific semantics associated with them. In some cases different client implementors decided to define and use keywords with different names, but the same semantics. Some server implementors decided to map such keywords automatically in order to improve cross client interoperability. In other cases, the same keywords have been used with different semantics, thus causing interoperability problems. This document attempts to prevent further incompatible uses of IMAP keywords by establishing an IMAP Keyword registry, and documenting a reserved space for standardized keywords. 3. IANA Considerations IANA is requested to establish a new registry for IMAP keywords. Registration of an IMAP keyword is requested by filling in the following template: Subject: Registration of IMAP keyword X IMAP keyword name: Purpose (description): Melnikov & Cridland Expires January 14, 2010 [Page 3] Internet-Draft IMAP4 Keyword Registry July 2009 Private or Shared on a server: (One of PRIVATE, SHARED or BOTH. PRIVATE means that each different user has own copy of the keyword. SHARED means that all different users see the same value of the keyword. BOTH means that an IMAP server can have the keyword as either private or shared.) Is it an advisory keyword or may it cause an automatic action: When/by whom the keyword is set/cleared: Related keywords: (for example "mutually exclusive with keywords Y and Z") Related IMAP capabilities: Security considerations: Published specification (recommended): Person & email address to contact for further information: Intended usage: (One of COMMON, LIMITED USE or OBSOLETE) Owner/Change controller: Note: (Any other information that the author deems interesting may be added here, for example if the keyword(s) is supported by existing clients.) and sending it via electronic mail to . Registration of an IMAP keyword intended for common use requires Expert Review. This can be performed by posting a review request to the Message Organization WG mailing list (or its replacement as chosen by the responsible Application Area Director). Keywords intended for widespread use SHOULD start with the "$" Melnikov & Cridland Expires January 14, 2010 [Page 4] Internet-Draft IMAP4 Keyword Registry July 2009 prefix. IMAP keywords intended for widespread use SHOULD be standardized in IETF Consensus documents. Registration of vendor specific keywords is done on First Come First Serve basis and doesn't require the Expert Review. However such review is still encouraged. Vendor specific keywords MUST start with the "vnd." prefix. [[anchor3: SHOULD this be followed by the company name?]] 3.1. Comments on IMAP Keywords' Registrations Comments on registered IMAP Keywords should first be sent to the "owner" of the mechanism and then to the mailing list designated to IMAP keyword review Section 3 Submitters of comments may, after a reasonable attempt to contact the owner and after soliciting comments on the IMAP mailing list, request IANA to attach their comment to the IMAP keyword registration itself by sending mail to . At IANA sole discretion, IANA may attach the comment to the IMAP keyword registration. 3.2. Change Control Once an IMAP keyword registration has been published by IANA, the author may request a change to its definition. The change request follows the same procedure as the registration request, with the exception of changes to the "Person & email address to contact for further information" and "Owner/Change controller" fields. The latter can be changed by the owner by sending informing IANA; this can be done without discussion or review. The IESG may reassign responsibility for an IMAP keyword. The most common case of this will be to enable changes to be made to mechanisms where the author of the registration has died, moved out of contact or is otherwise unable to make changes that are important to the community. IMAP keyword registrations may not be deleted; keywords which are no longer believed appropriate for use can be declared OBSOLETE by a change to their "intended usage" field. The IESG is considered to be the owner of all IMAP keywords which are on the IETF standards track. 3.3. Initial registrations IANA is requested to register the following IMAP Keyword in the registry established in this document: Melnikov & Cridland Expires January 14, 2010 [Page 5] Internet-Draft IMAP4 Keyword Registry July 2009 Subject: Registration of IMAP keyword $MDNSent IMAP keyword name: $MDNSent Purpose (description): Specifies that a Message Disposition Notification (MDN) must not be sent for any message annotated with the $MDNSent IMAP keyword. Private or Shared on a server: SHARED Is it an advisory keyword or may it cause an automatic action: This keyword can cause automatic action by the client. See [RFC3503] for more details When/by whom the keyword is set/cleared: This keyword is set by an IMAP client when it decides to act on a MDN request, or when uploading a sent or draft message. Related keywords: None Related IMAP capabilities: None Security considerations: See section 6 of [RFC3503] Published specification (recommended): [RFC3503] Person & email address to contact for further information: Alexey Melnikov Intended usage: COMMON Owner/Change controller: IESG Melnikov & Cridland Expires January 14, 2010 [Page 6] Internet-Draft IMAP4 Keyword Registry July 2009 Note: 4. Security Considerations IMAP Keywords are one of the base IMAP features [RFC3501]. This document doesn't change their behaviour, so it is not adding new security issues. A particular IMAP keyword might have specific security considerations, which are documented in IMAP keyword registration template standardized by this document. 5. Acknowledgements The creation of this document was prompted by one of many discussions on the IMAP mailing list. John Neystadt co-authored the first revision of this document. Special thanks to Chris Newman, David Harris, Lyndon Nerenberg and Mark Crispin for reviewing the document. However all errors or omissions must be attributed to the author of this document. The author would also like to thank the developers of Mozilla mail clients for providing food for thoughts. 6. References 6.1. Normative References [Kwds] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", RFC 2119, March 1997. [RFC3501] Crispin, M., "INTERNET MESSAGE ACCESS PROTOCOL - VERSION 4rev1", RFC 3501, March 2003. 6.2. Informative References [RFC3503] Melnikov, A., "Message Disposition Notification (MDN) profile for Internet Message Access Protocol (IMAP)", RFC 3503, March 2003. Melnikov & Cridland Expires January 14, 2010 [Page 7] Internet-Draft IMAP4 Keyword Registry July 2009 Authors' Addresses Alexey Melnikov Isode Limited 5 Castle Business Village 36 Station Road Hampton, Middlesex TW12 2BX UK Email: Alexey.Melnikov@isode.com URI: http://www.melnikov.ca/ Dave Cridland Isode Limited 5 Castle Business Village 36 Station Road Hampton, Middlesex TW12 2BX UK Email: dave.cridland@isode.com Melnikov & Cridland Expires January 14, 2010 [Page 8]