Sieve working group R. George Internet-Draft B. Leiba Intended status: Standards Track Huawei Technologies Expires: May 27, 2011 November 23, 2010 Sieve Vacation Extension: "Seconds" parameter draft-ietf-sieve-vacation-seconds-03 Abstract This document describes a further extension to the Sieve Vacation extension, allowing multiple auto-replies to the same sender in a single day by adding a ":seconds" parameter. 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 May 27, 2011. Copyright Notice Copyright (c) 2010 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. George & Leiba Expires May 27, 2011 [Page 1] Internet-Draft Sieve Vacation: Seconds parameter November 2010 Table of Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3 1.1. Terminology Used in This Document . . . . . . . . . . . . . . 3 2. The ':seconds' Parameter . . . . . . . . . . . . . . . . . . 3 3. Examples . . . . . . . . . . . . . . . . . . . . . . . . . . 4 4. Security Considerations . . . . . . . . . . . . . . . . . . . 5 5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 5 5.1. Registration of Sieve Extension . . . . . . . . . . . . . . . 5 6. References . . . . . . . . . . . . . . . . . . . . . . . . . 5 6.1. Normative References . . . . . . . . . . . . . . . . . . . . 5 6.2. Informative References . . . . . . . . . . . . . . . . . . . 5 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . 6 George & Leiba Expires May 27, 2011 [Page 2] Internet-Draft Sieve Vacation: Seconds parameter November 2010 1. Introduction The Sieve [RFC5228] Vacation extension [RFC5230] defines a mechanism to generate automatic replies to incoming email messages. Through the ":days" parameter, it limits the number of auto-replies to the same sender to one per [n] days, for a specified number of days. But there are cases when one needs more granularity, if one would like to generate "vacation" replies more frequently. This extension defines a ":seconds" parameter to provide more granularity for such situations. 1.1. Terminology Used in This Document The upper-case 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 [RFC2119]. 2. The ':seconds' Parameter The purpose of the ":seconds" parameter is to specify the minimum time interval (in seconds) between consecutive auto-replies to a given sender. The ":seconds" value, if specified, is used instead of the ":days" value, and works in a similar way (see the Vacation extension [RFC5230] for details). Only one of ":days" and ":seconds" is allowed -- use of both parameters in the same vacation action MUST result in a Sieve processing error. The capability string associated with this extension is "vacation- seconds". Note that "vacation-seconds" implies "vacation", and a script with "vacation-seconds" in a "require" list can omit "vacation" from that list. The time value is specified in seconds, and MUST be greater than or equal to 0 and less than 2**31. All valid values MUST be accepted without error, but sites MAY define a minimum value to actually be used if a smaller value is specified, and/or a maximum value to be used if a larger value is specified. If a site imposes a maximum value, that value MUST be at least 86400 (one day). If ":seconds 0" is specified and used, it means that all auto-replies are sent, and no attempt is made to suppress consecutive replies. This differs from the base vacation specification, which does not allow a time period of zero (":days 0" is forbidden); the change is necessary to allow operation of an auto-responder (see [I-D.ietf-sieve-autoreply], and note especially example 4 in section George & Leiba Expires May 27, 2011 [Page 3] Internet-Draft Sieve Vacation: Seconds parameter November 2010 3 of that document). If ":seconds" and ":days" are both omitted, a site-defined interval is used (see [RFC5230]). Usage: vacation [":days" number | ":seconds" number] [":subject" string] [":from" string] [":addresses" string-list] [":mime"] [":handle" string] 3. Examples This example will automatically reply to senders with a message that the recipient is in a meeting. Multiple replies to the same sender will only be sent every half hour (1800 seconds). require ["vacation-seconds"]; vacation :addresses ["tjs@example.edu", "ts4z@landru.example.edu"] :seconds 1800 "I am in a meeting, and do not have access to email."; This example is used to send an acknowledgment to every message received. A :seconds value of zero is used to reply to every message, with no removal of duplicates to the same sender. This requires that the Sieve engine allow an interval of zero; if it does not, and it imposes a minimum value, not every message will receive an auto-reply. require ["vacation-seconds"]; vacation :handle "auto-resp" :seconds 0 "Your request has been received. A service representative will contact you as soon as possible, usually within one business day."; George & Leiba Expires May 27, 2011 [Page 4] Internet-Draft Sieve Vacation: Seconds parameter November 2010 4. Security Considerations Security considerations for the Sieve Vacation extension [RFC5230] apply equally here. In addition, implementations SHOULD consider the number of auto-replies that might be generated by allowing small values of ":seconds" (including 0), and MAY impose additional limits on that number. See the Security Considerations section of RFC 3834 [RFC3834] for a fuller discussion. 5. IANA Considerations 5.1. Registration of Sieve Extension To: iana@iana.org Subject: Registration of new Sieve extension Capability name: vacation-seconds Description: adds the ":seconds" parameter to the Sieve Vacation extension. Implementations that support this MUST also support "vacation". RFC number: this RFC Contact address: The Sieve discussion list 6. References 6.1. Normative References [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, March 1997. [RFC3834] Moore, K., "Recommendations for Automatic Responses to Electronic Mail", RFC 3834, August 2004. [RFC5228] Guenther, P. and T. Showalter, "Sieve: An Email Filtering Language", RFC 5228, January 2008. [RFC5230] Showalter, T. and N. Freed, "Sieve Email Filtering: Vacation Extension", RFC 5230, January 2008. 6.2. Informative References [I-D.ietf-sieve-autoreply] George, R., Leiba, B., and A. Melnikov, "Sieve Email Filtering: Use of Presence Information with Auto Responder functionality", draft-ietf-sieve-autoreply-02 (work in progress), October 2010. George & Leiba Expires May 27, 2011 [Page 5] Internet-Draft Sieve Vacation: Seconds parameter November 2010 Authors' Addresses Robins George Huawei Technologies Bangalore, Karnataka 560071 India Phone: +91-080-41117676 Email: robinsgv@gmail.com Barry Leiba Huawei Technologies Phone: +1 646 827 0648 Email: barryleiba@computer.org URI: http://internetmessagingtechnology.org/ George & Leiba Expires May 27, 2011 [Page 6]