A new Request for Comments is now available in online RFC libraries. RFC 7505 Title: A "Null MX" No Service Resource Record for Domains That Accept No Mail Author: J. Levine, M. Delany Status: Standards Track Stream: IETF Date: June 2015 Mailbox: standards@taugh.com, mx0dot@yahoo.com Pages: 6 Characters: 12534 Updates/Obsoletes/SeeAlso: None I-D Tag: draft-ietf-appsawg-nullmx-10.txt URL: https://www.rfc-editor.org/info/rfc7505 DOI: http://dx.doi.org/10.17487/RFC7505 Internet mail determines the address of a receiving server through the DNS, first by looking for an MX record and then by looking for an A/AAAA record as a fallback. Unfortunately, this means that the A/AAAA record is taken to be mail server address even when that address does not accept mail. The No Service MX RR, informally called "null MX", formalizes the existing mechanism by which a domain announces that it accepts no mail, without having to provide a mail server; this permits significant operational efficiencies. This document is a product of the Applications Area Working Group Working Group of the IETF. This is now a Proposed Standard. STANDARDS TRACK: This document specifies an Internet Standards Track protocol for the Internet community, and requests discussion and suggestions for improvements. Please refer to the current edition of the Official Internet Protocol Standards (https://www.rfc-editor.org/standards) for the standardization state and status of this protocol. Distribution of this memo is unlimited. This announcement is sent to the IETF-Announce and rfc-dist lists. To subscribe or unsubscribe, see https://www.ietf.org/mailman/listinfo/ietf-announce https://mailman.rfc-editor.org/mailman/listinfo/rfc-dist For searching the RFC series, see https://www.rfc-editor.org/search For downloading RFCs, see https://www.rfc-editor.org/rfc.html Requests for special distribution should be addressed to either the author of the RFC in question, or to rfc-editor@rfc-editor.org. Unless specifically noted otherwise on the RFC itself, all RFCs are for unlimited distribution. The RFC Editor Team Association Management Solutions, LLC