Shepherd writeup

Document Shepherd Writeup
“The Require-Recipient-Valid-Since Header Field and SMTP Service Extension”
By J. Trent Adams
January 23, 2013.

1. Summary

The document shepherd is J. Trent Adams. The responsible Area Director is Barry Leiba.

This document defines an extension for the Simple Mail Transfer Protocol called
RRVS, and a header field called Require-Recipient-Valid-Since, to provide a method 
for senders to indicate to receivers the time when the sender last confirmed the 
ownership of the target mailbox.  This can be used to detect changes of mailbox 
ownership, and thus prevent mail from being delivered to the wrong party.

The intended use of these facilities is on automatically generated messages that 
might contain sensitive information, though it may also be useful in other applications.

The Applications Area Work Group (AppsArea WG) is requesting that the document 
become a Proposed Standard.

2. Review and Consensus

The document has gone through 7 iterations, starting with the -00 draft published as 
an I-D on August 18, 2013, and the most recent -05 version posted on January 10, 
2014.  Each iteration represents updates to the document following discussion on the 
AppsArea WG discussion list (  There have been 
approximately a dozen active contributors throughout the process, representing strong 

By way of example of the impact of the review by the AppsArea WG, the initial draft 
focused on the addition of a header field within the message as a means to identifying 
continuous ownership of the mailbox.  Through the conversation, however, it became 
clear that the community felt it was more appropriate to perform the validation through 
the addition of an SMTP extension.  At the conclusion of the discussion, the 
document was updated and now includes an SMTP extension.

The -06 version includes clarifications and addresses issues that were brought up on
the list in response to a call for final comments.  The comments on the -05 version
were incorporated to the point where those who contributed them responded that they
were comfortable that the -06 version effectively addressed their comments.

As of this writing, the document appears to have reached consensus support and
it is the opinion of this shepherd that it is ready to be moved forward.

3. Intellectual Property

The document was developed within the AppsArea WG in which all contributions by 
the participants, including the named authors, were made in conformance with BCPs 
78 and 79 and the copyright of the document has been granted to the IETF Trust.  
The authors have further confirmed that they have no knowledge of any 
encumbrances on their contributions, or any contributions made by other participants.

4. Other Points

The document requests the following be registered by IANA:

* The registration in the “Permanent Message Header Field Names” registry of a new 
Header Field Name: “Require-Recipient-Valid-Since”.  This request is made to support 
the header field option described in this document.  No expert review is required.

* The registration in the “SMTP Service Extension in the Mail Parameters” registry of 
a new EHLO Keyword: ”RRVS”.  No additional parameters are being requested.  No 
expert review is required.

* The registration of two additional “Enumerated Status Codes” within the “Simple Mail 
Transfer Protocol (SMTP) Enhanced Status Codes” registry: One to identify when a 
mailbox owner has changed, the other when a domain owner has changed.  At the 
time of this review, the requested entries are: “X.7.17” and “X.7.18”.  No expert 
review is required.

* The registration in the “Email Authentication Methods” table of the “Email 
Authentication Parameters” registry of a new Method: “rrvs”, with a ptype: “smtp”, and 
property: “rcptto”.  An expert review is required, though no expert reviewer has been 
identified at this time.