Postmaster Convention for X.400 Operations (RFC1648)
Original Publication Date: 1994-Jul-01
Included in the Prior Art Database: 2000-Sep-12
Internet Society Requests For Comment (RFCs)
Both STD 11, RFC 822  and STD 3, RFC 1123  (Host Requirements) require that the email address "postmaster" be supported at all hosts. This paper extends this concept to X.400 mail domains which have registered RFC 1327 mapping rules, and which therefore appear to have normal RFC822-style addresses.
Network Working Group A. Cargille
Request for Comments: 1648 University of Wisconsin
Category: Standards Track July 1994
Postmaster Convention for X.400 Operations
Status of this Memo
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 "Internet
Official Protocol Standards" (STD 1) for the standardization state
and status of this protocol. Distribution of this memo is unlimited.
Both STD 11, RFC 822  and STD 3, RFC 1123  (Host Requirements)
require that the email address "postmaster" be supported at all
hosts. This paper extends this concept to X.400 mail domains which
have registered RFC 1327 mapping rules, and which therefore appear to
have normal RFC822-style addresses.
1. Postmaster Convention in RFC822
Operating a reliable, large-scale electronic mail (email) network
requires cooperation between many mail managers and system
administrators. As noted in RFC 822 , often mail or system
managers need to be able to contact a responsible person at a remote
host without knowing any specific user name or address at that host.
For that reason, both RFC 822 and the Internet Host Requirements 
require that the address "postmaster" be supported at every Internet
2. Postmaster Convention and X.400
However, RFC 822 is not the only email protocol being used in the
Internet. Some Internet sites are also running the X.400 (1984) 
and X.400 (1988)  email protocols. RFC 1327 specifies how to map
between X.400 and RFC 822 addresses . When mapping rules are
used, addresses map cleanly between X.400 and RFC 822. In fact, it
is impossible to determine by inspecting the address whether the
recipient is an RFC 822 mail user or an X.400 mail user.
A paper by Rob Hagens and Alf Hansen describes an X.400 community
known as the "Global Open MHS Community" (GO-MHS) . Many mail
domains in the GO-MHS Community have registered RFC 1327 mapping
rules. Therefore, users in those domains have RFC 822-style email
addresses, and these email domains are a logical extension of the RFC
822 Internet. It is impossible to tell by inspecting a user's
address whether the user receives RFC 822 mail or X.400 mail.
Since these addresses appear to be standard RFC 822 addresses, mail
managers, mailing list managers, host administrators, and users
expect to be able to simply send mail to "postmaster@domain"...