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RFC 458 UNKNOWN MAIL · FTP

Mail retrieval via FTP

Two proposed FTP commands for reading mail stored at another site.

On rfc-editor.org ↗
PUBLISHED
February 1973
AUTHORS
R.D. Bressler, R. Thomas
STREAM
Legacy
PROPOSED COMMANDS
RDMF and RDML
RDMF MAIL PATH
Data connection
RDML MAIL AND REPLIES
TELNET connection
RDML MAIL-FOLLOWS REPLY
152
DOI
10.17487/RFC0458

RFC text

Original text · RFC Editor View on rfc-editor.org ↗ 
Network Working Group                                        B. Bressler
Request for Comments: 458                                        BBN-NET
NIC: 14378                                                     B. Thomas
                                                               BBN-TENEX
                                                        20 February 1973


                         Mail Retrieval via FTP

   We propose two new FTP commands called ReaDMailFile and ReaDMail.
   These commands are intended to be symmetric with respect to the
   current MLFL and MAIL commands.  They would allow a user to read his
   mail at one or more sites without incurring the overhead of logging
   in and without having to use several different retrieval methods.
   The user might go further and create a program to go around to all
   the server sites and retrieve his mail for him.  The current FTP
   mechanisms provide for password protection, should security be
   required.

   This proposal brings into focus, once again, the problems of
   different users with the same ID, and to a lesser extent, one user
   with multiple IDs.  This RFC does not attempt to address these issues
   at this time, as much effort is currently being devoted to them.
   However, we believe that a satisfactory system for network mail
   should include a mechanism to enable each user to have mail for him
   sent to a single repository (ideally, the site of his choice).  We
   further believe that the two commands proposed here would be useful
   in such an environment as well as within the current network
   environment.

   The format of the commands is

   COMMAND    REPLY
              success        fail

   RDMF       200,250,330    433,450,451,454,455,457,500,507
              secondary replies:
              252            452

   RDML       152,330        433,450,451,455,500,507

   The success reply 200 would take the text "NO MAIL NOW".  For the
   RDMF command the mail itself is transferred over the data connection,
   and the FTP replies come over the TELNET connection.

   For the RDML command both the mail and the FTP replies come over the
   TELNET connection.  The reply 152 is a new code meaning "mail text
   follows" the text that follows may be "NO MAIL NOW".


          [This RFC was put into machine readable form for entry]
     [into the online RFC archives by Helene Morin, Via Genie 12/1999]

ISO Plain Language

On this page
PROBLEMUsers could have mail at more than one network site, but reading it required logging in and using different retrieval methods.
MECHANISMRFC 458 proposes RDMF and RDML as read counterparts to FTP's MLFL and MAIL commands. RDMF sends mail over the data connection; RDML sends mail and replies over the TELNET connection.
THE PROPOSALThe proposal describes two ways to retrieve mail and leaves the problems of users with multiple IDs for later work.

§1Why Add Mail-Reading Commands

FTP already had the MLFL and MAIL commands for sending mail. RFC 458 proposes matching commands for reading it, so a user could retrieve mail from one or more sites without logging in at each site or using different retrieval methods.

The authors say FTP's existing password protection could be used when security is required. They also identify the problem of different people sharing an ID, and one person having several IDs, but leave those issues unresolved.

The proposal adds ways to read mail through FTP, matching its existing ways to send mail. It does not solve how to identify people who share or have several user IDs.

§2Two Ways to Return Mail

RDMF (ReaDMailFile) transfers the mail over FTP's data connection. FTP replies use the TELNET connection. Its listed successful replies include 200, 250 and 330; the 200 reply carries the text NO MAIL NOW.

RDML (ReaDMail) sends both the mail and FTP replies over the TELNET connection. It introduces reply 152, meaning that mail text follows; that text may say NO MAIL NOW. The RFC also lists success and failure reply codes for both commands.

RDMF puts the mail on a separate data connection. RDML puts the mail and its status replies together on the TELNET connection.

§3A Proposal for Network Mail

The authors suggest that a useful network mail system should let each person's mail reach one repository, ideally at a site the person chooses. They expect the proposed commands could be useful both in that arrangement and in the network as it then existed.

The RFC describes the commands as a proposal and does not report implementation or adoption. Its focus is mail retrieval; the identity problems it raises are explicitly left for other work.

The authors want mail to be gathered in one chosen place for each person. This RFC proposes retrieval commands but does not say that they were implemented.