Mail Transfer Protocol: ISI TOPS20 MTP-NIMAIL interface
How MTP and NIMAIL exchange mail on ISI TOPS-20.
Sluizer, S. and J. Postel, "Mail Transfer Protocol: ISI TOPS20 MTP-NIMAIL interface", RFC 786, DOI 10.17487/RFC0786, July 1981, <https://www.rfc-editor.org/info/rfc786>.
@misc{rfc786,
series = {Request for Comments},
number = 786,
howpublished = {RFC 786},
publisher = {RFC Editor},
doi = {10.17487/RFC0786},
url = {https://www.rfc-editor.org/info/rfc786},
author = {S. Sluizer and J. Postel},
title = {{Mail Transfer Protocol: ISI TOPS20 MTP-NIMAIL interface}},
pagetotal = 2,
year = 1981,
month = jul,
} RFC text
Contents
Network Working Group S. Sluizer
Request for Comments: 786 J. Postel
ISI
July 1981
MAIL TRANSFER PROTOCOL:
ISI TOPS20 MTP-NIMAIL INTERFACE
INTRODUCTION
This document defines the ISI TOPS20s interface between the Mail
Transfer Protocol (MTP) and the Network Independent Mail Protocol
(NIMAIL) in terms of the files which implement it. The internal
structure and name of each file is described below.
For a complete understanding of the MTP protocol as well as the terms
used within this document, see RFC 780 "Mail Transfer Protocol", RFC
784 "ISI TOPS20 Implementation", and RFC 785 "ISI TOPS20 File
Defintitions". The NIMAIL is documented in IEN 169, "A Simple
NIFTP-Based Mail System".
DESCRIPTION
1. NIMAIL to MTP
NIMAIL will present mail for processing by MTP using the files
specified in RFC 785.
2. MTP to NIMAIL
MTP will present mail for processing by NIMAIL in files of the
following form:
address <CR><LF>
address <CR><LF>
address <CR><LF>
<CR><LF>
Via: USC-ISIE; date-time <CR><LF>
header
.
.
.
<CR><LF>
body
.
.
.
Where each address is of the form:
Sluizer & Postel Page [1]
ISI TOPS20 MTP-NIMAIL Interface
user%host%host%host@host
And each address in the same file has the same "@host" part.
The date-time will be in the default TOPS20 ODTIM format
"dd-mmm-yy hh:mm:ss" (24 hour time).
The files will named "arbitrary.NIMAIL.-1", where "arbitrary" will
be somesort of date-time encoding for human uses. The NIMAIL will
not care in the least what the "arbitrary" part is. These files
will be placed into the NIMAIL directory on ISIE.
DISCUSSION
The NIMAIL and MTP will each perform a transformation of the address
information to create the appropriate input for the other system.
NIMAIL to MTP
The mail that arrives at NIMAIL with the information
joe%hostx%hosty%hostz@isie
will be presented to MTP with the information
FROM: <NIMAIL@ISIE>
TO: <@hostz,@hosty,joe@hostx>
MTP to NIMAIL
The mail that arrives at MTP with the information
FROM: <sam@SRI-NIC>
TO: <@ISIE,@hostz,@hosty,joe@hostx>
will be presented to NIMAIL with the information
joe%hostx%hosty@hostz
Via: ISIE
Page [2] Sluizer & Postel
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On this page
§1Introduction
RFC 786 defines how the Mail Transfer Protocol (MTP) and the Network Independent Mail (NIMAIL) system exchange messages on ISI's TOPS-20 system. NIMAIL is a mail system based on NIFTP (the Network Independent File Transfer Protocol), documented in IEN 169. This RFC specifies the file interface, address transformations, and directory conventions.
This memo is about two mail systems on the same computer and how they pass mail back and forth.
§2Bidirectional Exchange
Mail flows in two directions. When NIMAIL sends mail to MTP, it uses the file format from RFC 785: a control file pointing to a mail file, with FROM and TO addresses. When MTP sends mail to NIMAIL, it creates files with a different structure. MTP files contain a list of recipient addresses, followed by a Via: line with the sending host and timestamp (in TOPS-20 format dd-mmm-yy hh:mm:ss), followed by mail headers and body. Files are named arbitrarily with a .NIMAIL.-1 extension and placed in the NIMAIL directory.
Mail going in can be in one format, and mail going out can be in another. Each system transforms the address list so the other understands it.
§3Address Format Conversion
NIMAIL uses a source-routed address format with percent signs and a final host, such as joe%hostx%hosty%hostz@isie. When NIMAIL sends to MTP, this becomes FROM: <NIMAIL@ISIE> and TO: <@hostz,@hosty,joe@hostx> in MTP path format. Conversely, when MTP sends to NIMAIL an address like FROM: <sam@SRI-NIC> with TO: <@ISIE,@hostz,@hosty,joe@hostx>, it becomes joe%hostx%hosty@hostz with Via: ISIE in the NIMAIL file. The key constraint is that all addresses in a single NIMAIL file from MTP must share the same final @host part.
MTP uses angle brackets and route symbols, NIMAIL uses percent signs. The two systems automatically translate between the two styles.