Internet Engineering Task Force (IETF) R. George
Request for Comments: 6131 B. Leiba
Category: Standards Track Huawei Technologies
ISSN: 2070-1721 July 2011
Sieve Vacation Extension: "Seconds" Parameter
George & Leiba Standards Track [Page 1]
RFC 6131 Sieve Vacation: Seconds Parameter July 2011
Table of Contents
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.
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" or ":seconds" is allowed -- use of both parameters in the same vacation action MUST result in a Sieve processing error.
George & Leiba Standards Track [Page 2]
RFC 6131 Sieve Vacation: Seconds Parameter July 2011
1. Call the value specified "v(spec)".
George & Leiba Standards Track [Page 3]
RFC 6131 Sieve Vacation: Seconds Parameter July 2011 3. ExamplesThe following 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).
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 ExtensionTo: 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: RFC 6131 Contact address: The Sieve discussion list <sieve@ietf.org>
George & Leiba Standards Track [Page 4]
RFC 6131 Sieve Vacation: Seconds Parameter July 2011 6. References 6.1. Normative References[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
6.2. Informative References
[RFC6133] George, R., Leiba, B., and A. Melnikov, "Sieve Email