7Internet Engineering Task Force (IETF) R. George
8Request for Comments: 6131 B. Leiba
9Category: Standards Track Huawei Technologies
10ISSN: 2070-1721 July 2011
13 Sieve Vacation Extension: "Seconds" Parameter
17 This document describes a further extension to the Sieve Vacation
18 extension, allowing multiple auto-replies to the same sender in a
19 single day by adding a ":seconds" parameter.
23 This is an Internet Standards Track document.
25 This document is a product of the Internet Engineering Task Force
26 (IETF). It represents the consensus of the IETF community. It has
27 received public review and has been approved for publication by the
28 Internet Engineering Steering Group (IESG). Further information on
29 Internet Standards is available in Section 2 of RFC 5741.
31 Information about the current status of this document, any errata,
32 and how to provide feedback on it may be obtained at
33 http://www.rfc-editor.org/info/rfc6131.
37 Copyright (c) 2011 IETF Trust and the persons identified as the
38 document authors. All rights reserved.
40 This document is subject to BCP 78 and the IETF Trust's Legal
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42 (http://trustee.ietf.org/license-info) in effect on the date of
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45 to this document. Code Components extracted from this document must
46 include Simplified BSD License text as described in Section 4.e of
47 the Trust Legal Provisions and are provided without warranty as
48 described in the Simplified BSD License.
58George & Leiba Standards Track [Page 1]
60RFC 6131 Sieve Vacation: Seconds Parameter July 2011
65 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 2
66 1.1. Terminology Used in This Document . . . . . . . . . . . . . 2
67 2. The ':seconds' Parameter . . . . . . . . . . . . . . . . . . . 2
68 3. Examples . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
69 4. Security Considerations . . . . . . . . . . . . . . . . . . . . 4
70 5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . . 4
71 5.1. Registration of Sieve Extension . . . . . . . . . . . . . . 4
72 6. References . . . . . . . . . . . . . . . . . . . . . . . . . . 5
73 6.1. Normative References . . . . . . . . . . . . . . . . . . . 5
74 6.2. Informative References . . . . . . . . . . . . . . . . . . 5
78 The Sieve [RFC5228] Vacation extension [RFC5230] defines a mechanism
79 to generate automatic replies to incoming email messages. Through
80 the ":days" parameter, it limits the number of auto-replies to the
81 same sender to one per [n] days, for a specified number of days. But
82 there are cases when one needs more granularity, if one would like to
83 generate "vacation" replies more frequently.
85 This extension defines a ":seconds" parameter to provide more
86 granularity for such situations.
881.1. Terminology Used in This Document
90 The upper-case key words "MUST", "MUST NOT", "REQUIRED", "SHALL",
91 "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and
92 "OPTIONAL" in this document are to be interpreted as described in RFC
952. The ':seconds' Parameter
97 The purpose of the ":seconds" parameter is to specify the minimum
98 time interval (in seconds) between consecutive auto-replies to a
99 given sender. The ":seconds" value, if specified, is used instead of
100 the ":days" value, and works in a similar way (see the Vacation
101 extension [RFC5230] for details). Only one of ":days" or ":seconds"
102 is allowed -- use of both parameters in the same vacation action MUST
103 result in a Sieve processing error.
105 The capability string associated with this extension is "vacation-
106 seconds". Note that "vacation-seconds" implies "vacation", and a
107 script with "vacation-seconds" in a "require" list can omit
108 "vacation" from that list.
114George & Leiba Standards Track [Page 2]
116RFC 6131 Sieve Vacation: Seconds Parameter July 2011
119 The time value is specified in seconds, and MUST be greater than or
120 equal to 0 and less than 2**31. All valid values, from 0 to 2**31,
121 MUST be accepted without error. Sites MAY define a minimum effective
122 value and/or a maximum effective value. If a site chooses to do
125 1. Call the value specified "v(spec)".
127 2. Call the minimum effective value "v(min)".
129 3. Call the maximum effective value "v(max)".
131 4. Call the actual effective value used by the processor "v(eff)".
133 5. The following apply for determining v(eff):
135 * If 0 <= v(spec) < v(min), then v(eff) = v(min).
137 * If v(min) <= v(spec) <= v(max), then v(eff) = v(spec).
139 * If v(max) < v(spec) <= 2**31, then v(eff) = v(max).
141 If a site imposes a maximum effective value, that value MUST be at
142 least 86400 (one day).
144 If ":seconds 0" is specified and used, it means that all auto-replies
145 are sent, and no attempt is made to suppress consecutive replies.
146 This differs from the base vacation specification, which does not
147 allow a time period of zero (":days 0" is forbidden); the change is
148 necessary to allow operation of an auto-responder (see [RFC6133], and
149 note especially example 4 in section 3 of that document).
151 If ":seconds" and ":days" are both omitted, a site-defined interval
152 is used (see [RFC5230]).
154 Usage: vacation [":days" number | ":seconds" number]
157 [":addresses" string-list]
170George & Leiba Standards Track [Page 3]
172RFC 6131 Sieve Vacation: Seconds Parameter July 2011
177 The following example will automatically reply to senders with a
178 message that the recipient is in a meeting. Multiple replies to the
179 same sender will only be sent every half hour (1800 seconds).
181 require ["vacation-seconds"];
182 vacation :addresses ["tjs@example.edu", "ts4z@landru.example.edu"]
184 "I am in a meeting, and do not have access to email.";
186 The following example is used to send an acknowledgment to every
187 message received. A :seconds value of zero is used to reply to every
188 message, with no removal of duplicates to the same sender. This
189 requires that the Sieve engine allow an interval of zero; if it does
190 not, and it imposes a minimum value, not every message will receive
193 require ["vacation-seconds"];
195 vacation :handle "auto-resp" :seconds 0
196 "Your request has been received. A service
197 representative will contact you as soon as
198 possible, usually within one business day.";
2004. Security Considerations
202 Security considerations for the Sieve Vacation extension [RFC5230]
203 apply equally here. In addition, implementations SHOULD consider the
204 number of auto-replies that might be generated by allowing small
205 values of ":seconds" (including 0), and MAY impose additional limits
206 on that number. See the Security Considerations section of RFC 3834
207 [RFC3834] for a fuller discussion.
2095. IANA Considerations
2115.1. Registration of Sieve Extension
214 Subject: Registration of new Sieve extension
215 Capability name: vacation-seconds
216 Description: adds the ":seconds" parameter to the Sieve Vacation
217 extension. Implementations that support this MUST also support
220 Contact address: The Sieve discussion list <sieve@ietf.org>
226George & Leiba Standards Track [Page 4]
228RFC 6131 Sieve Vacation: Seconds Parameter July 2011
2336.1. Normative References
235 [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
236 Requirement Levels", BCP 14, RFC 2119, March 1997.
238 [RFC3834] Moore, K., "Recommendations for Automatic Responses to
239 Electronic Mail", RFC 3834, August 2004.
241 [RFC5228] Guenther, P. and T. Showalter, "Sieve: An Email Filtering
242 Language", RFC 5228, January 2008.
244 [RFC5230] Showalter, T. and N. Freed, "Sieve Email Filtering:
245 Vacation Extension", RFC 5230, January 2008.
2476.2. Informative References
249 [RFC6133] George, R., Leiba, B., and A. Melnikov, "Sieve Email
250 Filtering: Use of Presence Information with Auto-Responder
251 Functionality", RFC 6133, July 2011.
257 Bangalore, Karnataka 560071
260 Phone: +91-080-41117676
261 EMail: robinsgv@gmail.com
267 Phone: +1 646 827 0648
268 EMail: barryleiba@computer.org
269 URI: http://internetmessagingtechnology.org/
282George & Leiba Standards Track [Page 5]