{"draft":"draft-ietf-appsawg-nullmx-10","doc_id":"RFC7505","title":"A \"Null MX\" No Service Resource Record for Domains That Accept No Mail","authors":["J. Levine","M. Delany"],"format":["ASCII","HTML"],"page_count":"6","pub_status":"PROPOSED STANDARD","status":"PROPOSED STANDARD","source":"ART Area General Application Working Group","abstract":"Internet mail determines the address of a receiving server through\r\nthe DNS, first by looking for an MX record and then by looking for an\r\nA\/AAAA record as a fallback.  Unfortunately, this means that the\r\nA\/AAAA record is taken to be mail server address even when that\r\naddress does not accept mail.  The No Service MX RR, informally\r\ncalled \"null MX\", formalizes the existing mechanism by which a domain\r\nannounces that it accepts no mail, without having to provide a mail\r\nserver; this permits significant operational efficiencies.","pub_date":"June 2015","keywords":["DNS","e-mail"],"obsoletes":[],"obsoleted_by":[],"updates":[],"updated_by":[],"see_also":[],"doi":"10.17487\/RFC7505","errata_url":null}