<pre>NWG/RFC# 725                              DAY GRG 25-APR-77 12:41  38316
An RJE Protocol for a Resource Sharing Network



                    CAC Technical Memorandum No. 86

                           CCTC-WAD No. 7508

                          ARPANET RFC No. 725

                             NIC No. 38316

             An RJE Protocol for a Resource Sharing Network

                                   by

                                John Day

                            Gary R. Grossman

                            Prepared for the

                  Command and Control Technical Center

                         WWMCCS ADP Directorate

                                 of the

                     Defense Communications Agency

                         Washington, D.C. 20305

                             under contract

                            DCAl00-76-C-0088

                    Center for Advanced Computation

               University of Illinois at Urbana-Champaign

                         Urbana, Illinois 61801

                             March 1, 1977

    Approved for Release - Peter A. Alsberg, Principal Investigator</pre>
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An RJE Protocol for a Resource Sharing Network



For many users of the ARPANET, an RJE protocol is probably as important
in terms of utility as a TELNET (VTP) protocol.  In fact, the facilities
provided by a TELNET and an RJE protocol are probably of most interest
to most users of computer networks.  For these users, the net provides a
fast, cheap RJE surrogate, just as TELNET provides a telephone surrogate
for the timesharing user.  The collection (and layers) of protocols that
provide these services must be organized to efficiently support a wide
variety of applications and user needs.  They should not pose an undue
software burden on the user.

The "official" NETRJE protocol for the ARPANET has met an underwhelming
response from both the user and server community.  I believe there are
two basic reasons.  First, a large commitment of resources is necessary
to implement NETRJE.  Second, the protocol creates serious security
problems.

In order to support the ARPA RJE protocol, a user must implement User
Telnet, Server FTP, and User RJE, while a server must implement Server
Telnet, User FTP, and Server RJE.  In addition when an RJE session is
going on all three of these protocol implementations will be executing
for most of the life of the session.  This could entail considerable
burden for some systems.  Although it may not be out of line to require
a service to shoulder such burdens, it is out of line to require a user
to assume them in order to gain a rather basic service.  Most user
installations are oriented toward meeting their user's needs not toward
implementing large amounts of network software.  (In fact one of the
better aspects of the previous ARPANET protocol designs was that they
attempted to minimize the work for the user.  (It must be admitted
though that compassion for the user was not the reason for this
approach.)

In order to support a "hot line printer" (i.e., a job is automatically
printed when it is completed), the user must store his user code and
password for the output host at the server host.  This, of course,
presents a rather severe security problem.  Although the ARPANET can not
be made totally secure without massive revision, there are some basic
precautions that can be taken to protect users from being victimized by
every first year Computer Science student with access to the net.

The RJE protocol proposed here tries to mitigate the implementation
problems and security problems.  The protocol is designed to provide
three levels of service.  A user or server has the perogative to
implement the protocol at whatever level their resources allow.  The
service can then be upgraded to cleaner or more sophisticated approaches
when and if the opportunity arises.

This protocol is described in terms of the ARPANET.  Several aspects of





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An RJE Protocol for a Resource Sharing Network



the design (such as the reply structure) were made to coincide with
existing ARPANET conventions.  This was done to facilitate understanding
and limit the discussion to the protocol itself.  Although the protocol
is described in ARPANET terms, it should be applicable to other network
environments.

This paper is not considered to be complete in every detail.  It was
written primarily to elicit comments from the network community and to
measure the desire of the community to adopt such a procedure.  We have
tried to describe enough of the protocol so that the reader can get an
idea of how things are to work without getting bogged down in the detail
that would be necessary for implementation.  Below is an outline of the
final protocol document as presently conceived.  Sections marked with an
asterisk are to be provided later.






































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An RJE Protocol for a Resource Sharing Network



Introduction

Part I

   The NETRJE Models

      1.  Telnet (VTP) Model

      2.  Telnet with Data Transfer Model

      3.  Telnet with FTP Model

   Scenarios for the Models

*    Suggested Implementaton Schemes for Various Applications

Part II

   The Server RJE Commands

*        General Conventions

   Commands

   Replies

      Numerical List

      Command-Reply List

*         Details of the Data Transfer

*         Minimal Requirements for a User RJE

*         Minimal Requirements for a Server RJE

*         Glossary of Terms















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An RJE Protocol for a Resource Sharing Network



Part I THE NETRJE MODELS
------------------------

This section describes the proposed NETRJE protocol in a narrative form.
A formal definition will be included in Part II after review.  The
narrative should provide the general reader with the flavor of the
protocol without getting bogged down in unnecessary detail.  The
proposed NETRJE protocol provides three different models for job
submission and retrieval.  The three models can be characterized as 1)
RJE using Telnet only, 2) RJE using Telnet and Data Transfer, and 3) RJE
using FTP.  This approach provides flexibility for both implementors and
users.  User and server sites constrained by manpower or machine
resources may implement only the simpler models.  The user may use the
different models separately or in any consistent combination which best
suits his requirements and convenience.  Servers should assume that the
minimal implementation of a more sophisticated model includes the
minimal implementations of all less sophisticated models.  (There are,
however, certain minimal requirements that must be supported.)  This
secton will discuss each of these models in turn, and show each one can
be used to provide a useful network RJE functon.

This protocol does not contain the security difficulties of the present
protocol.  This has been avoided by requiring that the burden of
implementing the "hot line printer" or "hot card reader" be put on the
user system.  Thus, those systems which desire such a facility may still
support it.  The user implementaton will be slightly more complicated.
The trade-off is the increased security of the protocol.

End-to-end protocols are assumed to be available and to provide an
ordered, error free bit stream to the RJE protocol.  It is also assumed
that a suitable virtual terminal protocol such as Telnet, is used to
format the control connection.

RJE Using Only Telnet (VTP)
---------------------------

The intent of this model is, bluntly, to provide an official "quick and
dirty" form of the protocol.  Many organizatons, both users and servers,
are often confronted with problem of providing a service quickly or
within very tight budgetary constraints.  This model is intended for
these situations.  With this model, the user is required only to be able
to establish a Telnet connection via the RJE contact socket.  Commands,
replies, and data are all sent over the Telnet connecton.  Card input or
printer output has the appearance of coming from or going to the user's
terminal.  The user's system may allow output to be diverted from the
terminal to another device such as the line printer.  The technique of
diverting terminal output was used with great success in the MARK I ANTS





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An RJE Protocol for a Resource Sharing Network



systems where various devices were not assigned socket numbers as in a
TIP.  This technique is also useful for hosts that allow program access
to the network only through the user's Telnet connection.  This
situation may exist in the early phases of a server's availability to
the network.  When data is transferred in this mode an end-of-data
marker will be sent to aid the receiving host in determining when to
stop diverting the data.  This model will have to handle the problems of
data traveling on a connection essentially meant for control.  The use
of this data transfer mechanism is intended as an intermediate measure
required by limited resources.  For now we let it stand that the
designers are aware of the problems inherent in embedding commands or
replies in the data stream.  We will leave the exact resolution of the
problem to the formal definition.

This proposed NETRJE protocol uses a schedule verb, SCHED for job
submission. For this model, there are two forms of SCHED that are
relevant.  First, there is the "SCHED &lt;server pathname&gt;" form.  This
command indicates to the server that there exists at the server site a
file with all necessary job control information and data to define a
job.  The server will then attempt to place the job in the job queue and
reply to the user indicating success or failure and possibly a job-id.
This job-id will be used when inquiring about the job status or
retrieving the job's output.

When the job finishes, the server will take one of two actions:

   a)  if the user is still logged in, the server will send a reply
   notifying the user of his job completion; or,

   b)  if the user is not logged in, the server will save the status of
   the job which may later be interrogated via the STATUS command (see
   below).

The otherform of SCHED of relevance to this model has the syntax:

   SCHED INPUT &lt;CRLF&gt;&lt;data&gt;&lt;CRLF&gt;.&lt;CFLF&gt;

This allows the user to sit down at a terminal and type his own job
control or possibly a program.  It also allows those users whose local
systems provide a facility to transmit files with User TELNET to
transmit user input job fles in this way.  The RJE Server would insert
the job into the local job stream, returning the proper indication of
success or failure along with identification of the job.

Just as the SCHED command provides several ways for job submission, the
OUTPUT command provides several options for retrieving output.  The form






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   OUTPUT&lt;job-id&gt;&lt;server pathname&gt;DISCARD

is sent to the server to initiate the output to the user's site
according to output specifications defined by previous OUTDEF commands
(see below).  The optional DISCARD argument to the OUTPUT command
indicates, if present, that the file is to be destroyed after
transmission has completed successfully.

The OUTDEF command for a job may be sent at any time after the job has
been scheduled and before it is retrieved using the OUTPUT command.
This command will specify the parameters necessary to effect the
transfer of the output to the user or to define the disposition of the
output.  We realize that the OUTDEF &lt;job-id&gt;&lt;server pathname&gt; command
(indicating that output is to be placed in a file described by the
pathname) may be difficult for some systems to implement.  These systems
would merely respond negatively indicating their inability to perform
the function.

A scenario is now in order to illustrate the model.  The user has logged
in to Multics and is ready to submit an RJE job in the following way
(XXX will denote the as yet unspecified reply code for the reply):

   SCHED MY-JOB&gt;TREK

The system responds with a reply indicating the job has been submitted
successfully and returns a job-id, say XA1423.

   XXX JOB XA1423 was successfully submitted.

At some later time a message appears.

   XXX JOB XA1423 has completed.

The user or user process now sends OUTDEF XA1423 TELNET indicating that
the job should be sent on the TELNET connection.  A reply returns

   XXX last command successful.

The user now sends

   OUTPUT XA1423

and the server replies with

   XXX Output ready.  Type an empty line when ready.

The user then sends an empty line when he is read to receive the output.





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An RJE Protocol for a Resource Sharing Network



This exchange allows the user to effect output diversion at his local
site if necessary after he has confirmed the server is ready.

If the user had not wished to wait on his output and had logged off
after getting the successful submission, the next time the user logged
in he could inquire as to the status of the job or all jobs under his
usercode and then proceeded to output any or all of them.

RJE with TELNET and Data Transfer
---------------------------------

The previous model provided a minimal implementation for NETRJE.  This
model provides better data transfer facilities without requiring an FTP
implementation.  This model requires no new commands, but does
manipulate connections differently, so that data is not required to flow
on the command connection (see Fig. 2).  Data is sent on separate
default connections (unless otherwise specified) as in the CCN NETRJS
protocol.  However, for this protocol the defaults used will be the same
offsets from the control connection as those in FTP.

The use of this model is indicated to the Server by either the INDEF
command or a SCHED command with no arguments.  The INDEF command allows
the user to specify a socket other than the default socket as the source
of the input.  On receipt of the SCHED or INDEF indicating this
technique is to be used, the Server will attempt to connect to the
appropriate socket.  If a SCHED command was sent, the user protocol
interpreter could start sending cards as soon as the data connection is
established.  (It is assumed that the user interface has indicated to
the RJE protocol interpreter where the cards are to come from.)  If the
command was INDEF, then the Server will not start reading until the
SCHED is received.  Similarly, when the output is ready, either an
OUTDEF or OUTPUT command is sent to set up and start the printing.  The
INDEF and OUTDEF commands used with this mode will also allow moving
data to or from a TIP or printer.

This model requires definiton of actual data transfer formats for the
reader and printer lines.  We propose that the formats and connection
schemes of the present FTP be adopted.  This solution has the advantage
of not requiring extra coding efforts for users with FTP implementations
and may allow them to organize their FTP implementations and may allow
them to organize their FTP and NETRJE implementations in such a way as
to take advantage of common algorithms.  One might easily confuse this
solution with a revival of the Data Transfer Protocol.  Some thought on
a more rigorous definition of a Data Transfer Protocol for the common
use of FTP and RJE might be worthwhile in the future.







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An RJE Protocol for a Resource Sharing Network



Let us consider a scenario.

The user wishes to submit a card deck to the Server.  He then types

   SCHED&lt;CRLF&gt;

The Server opens a connection to the user's default card reader socket
while sending a reply to the user on the control connection.

   XXX attempting connection to card reader.

When the connection is opened, another reply:

   XXX transfer started

and when completed:

   XXX JOB XA 1423 was successfully submitted.

When the job completes and the completion message is sent to the user,
he may wish to send the output to his TIP printer on socket Y.  He will
then type

   OUTDEF XA1423 255, Y (255 being his host address).

The Server will then attempt to connect to the socket and will reply

   XXX printer connection successful.

When the user has satisfied himself all is in readiness, he will type

   OUTPUT XA1423

and the Server will start sending and reply to the user

   XXX print started.

When the transfer is complete the Server will close the data connection
and send an appropriate reply.













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An RJE Protocol for a Resource Sharing Network



NETRJE Using FTP
----------------

This model (illustrated in Fig. 3) uses FTP to effect the transfer of
the files.  It may be easier for some systems to use this sort of model
for more sophisticated RJE systems.  This is especially true if the
users desire to take input from the local file system or to send output
to the local file system rather than from an actual card reader or to an
actual line printer.  Although using the local file system is not
prohibited by the Data Transfer model, it may be easier to approach
through FTP.  Using FTP with NETRJE also allows the utilization of the
FTP server-server transfer mechanism to generate input from or direct
output to a third host.

The only new facility required by this model are the commands INPATH and
OUTPATH.  When using FTP to transfer input to the Server, the user must
know where to send the job so that it enters the job stream.  The INPATH
command returns as a reply such a legal pathname.  Thus the scenario for
job submission is as follows:  The user sends an INPATH command; the
Server responds with a legal Server pathname for the user.  The user
process starts sending the input to the file using FTP.  When transfer
is complete, the user sends a SCHED &lt;server pathname&gt; command.  When the
job has finished, the pathname created for the user may or may not
destroy the input file.  The OUTPATH command is similarily used to
identify the pathname for the output, so that it may be retrieved by
FTP.  Some systems may define file names in such a way that the user may
derive them from the parameters of his job.

Note on Replies

In all of the above examples we have refrained from defining actual
reply codes.  The intent is to use the same reply structure, and where
appropriate the same numbers, as described in <a href="./rfc640">RFC 640</a> "Revised FTP Reply
Codes".

Protocol Measurement

An integral part of any good protocol definition is a set of
measurements to allow evaluation of both the protocol and its
implementation.  This provides two functions:  1) It allows the protocol
designer to evaluate the protocol and make improvements.  2) It allows
the user of the protocol to know how expensive it is and to demand
improvements.  The proposed NETRJE protocol provides two sets of
measures - one for a particular session and one for overall performance.
These measurements may be elicited by the MEASURE command which will
take an argument with three values:  JOB (job statistics and cost
measurements), SESSION (measurements taken for this sesson), and GLOBAL





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(overall measurements of the performance of the protocol and its
implementation).  The command will return the measurements in a fixed
format reply.

The measurements reported for a job are:

   1.  CPU time,

   2.  I/O operations,

   3.  storage space time product,

   4.  job cost in dollars,

   5.  elapsed time the job waited before being executed, and

   6.  elapsed time for the job to execute.

The measures taken from a sesson are:

   1.  number of bits transferred,

   2.  transmission rate of input or output transfers,

   3.  the amount of CPU time, storage space-time product, and I/O
   operations for the session.

   4.  cost in dollars and cents.

The measures to be taken globally are:

   1.  frequency of commands and possibly command forms,

   2.  model frequency (which submission/retrieval model used),

   3.  transmission mode frequency,

   4.  total number of sessions,

   5.  transmission rate:  average, std. deviation, upper and lower
   bounds (also by transmission mode),

   6.  cpu time, storage space-time product, and I/O operations for both
   the protocol and jobs submitted:  average, std. deviation, and upper
   and lower bounds (overall as well as by model, transfer mode, and
   file size).  (The reason for including job statistics here is so that






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   management and systems personnel have some indication how the
   facility is being used.)

It is clear that it may be difficult to acquire some measures (such as
transmission rate) when NETRJE is using FTP.  This is unavoidable since
FTP is not metered.  The most straightforward solution is also to meter
FTP (hint).  For the final definition a close look will be given to the
subset that should be required.  Comments are welcome.  However, we
believe strongly that it is very important to know how a facility like
this is used as well as how well it performs.










































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An RJE Protocol for a Resource Sharing Network



Part II.  Preliminary Definition of NETRJE Commands
---------------------------------------------------

For purposes of discussion this section gives a very preliminary
definition of the NETRJE commands and their replies.  The intent is to
give a brief but not exhaustive definition of each command and its major
replies to give the flavor of the protocol.  We do not do this to
discourage nit-picking by critics, since we may actually overlook the
obvious on occasion, but merely to expedite the writing of this paper.

The reply scheme will follow the model of the revised FTP reply codes
described in <a href="./rfc640">RFC 640</a>.

Access Control

   USER &lt;usercode&gt;

   PASS &lt;password&gt;

   ACCT &lt;account&gt;

These perform the normal functions to log the user into the system.  The
replies to them are the standard ones in FTP.  It was never clear why
"account" was not included in the old NETRJE.  Presumably, if it's
necessary for an FTP or Telnet user, it will be necessary for an RJE
user.

REINIT

This command reinitializes the state of the NETRJE server process so
that it is ready for a new user.  If the transfer of data is in progress
for the previous user, it will be allowed to complete.

ABORT

This command is used to abort the transfer of data.  This command is
meaningful to the Server only if the data is being transferred over the
Telnet connection or the default data sockets.  If FTP is being used,
the execution of this command is the responsibility of the USER NETRJE
process.

BYE

This command causes the Server to log out the user and close the Telnet
connection.  If the transfer of data is in progress, the action of the
command will be delayed until the transfer is complete.






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SCHED &lt;input part&gt;&lt;output part&gt;

&lt;input part&gt;::= &lt;empty&gt;|&lt;server pathname&gt; [DISCARD]

   INPUT &lt;CRLF&gt;   &lt;text&gt;   &lt;CRLF&gt;.&lt;CRLF&gt;

output part ::= &lt;empty&gt;|&lt;server pathname&gt;[DISCARD]

server pathname ::= {locally recognizable string of characters
terminated by an ASCII NULL}

This command causes the input described by the &lt;input part&gt; to be
entered into the RJE job stream and the output produced to be disposed
of according to the &lt;output part&gt;.  The null condition for either
argument implies that the information has been previously specified or
is the default.

For the &lt;input part&gt;, the &lt;empty&gt; may imply two actions.  If an INDEF
command has previously specified a &lt;server pathname&gt;, input to the job
stream is taken from the file indicated by the file name.  If the INDEF
command has specified that the input is to come from a CCN-like data
transfer socket, the SCHED &lt;empty&gt; command is the signal for the Server
to start reading data.

The DISCARD modifier, if present, indicates that the file should be
discarded after it has been transmitted or it has been received and
executed.  If the input stream is to be sent on the Telnet connection,
the source may be a local device or a human user.  This facility is
provided for mini-hosts that can't use one of the other techniques and
for the user who wishes to enter job control directly at his terminal.

The empty for output specifies either the primary output file of the job
(the default) or a previously specified server pathname (OUTDEF
command).

Successful replies to this command should indicate any job-id assigned
by the local RJE system along with other status informaton.  Failure
would be because files did not exist, access was denied, etc.

OUTPUT &lt;output spec&gt;

&lt;output spec&gt;::= &lt;job-id&gt;&lt;xmsn part&gt;|&lt;job-id&gt;&lt;server pathname&gt;

&lt;xmsn part&gt;::= &lt;empty&gt;| /&lt;IO params&gt;

&lt;IO params&gt;::= &lt;xmsn params&gt;, &lt;dest&gt;






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This command indicates to the Server what output  is to be sent to the
user, how it is to be sent, and to whom.  The &lt;IO params&gt; part will
allow the specification of a host and socket so that output may be sent
to a TIP printer, or alternatively sent on the Telnet connection or to
the default data sockets.  This argument also specifies the format and
representation of the data.

When the Server receives this command, it will proceed to transmit the
output to the host in the prescribed manner.  The reply structure of
this command will depend on how the output is moved and will be
discussed in more detail later.

INPATH

This command returns to the user a legal pathname at the Server.  The
user may then transfer his input to this pathname for eventual
submission to the RJE facility.

OUTPATH

This command performs a similar function to INPATH.

DISCARD   &lt;job-file-id&gt;  |  &lt;server pathname&gt;

This allows the user to destroy input or output files associated with a
job.

INDEF     &lt;job-id&gt;&lt;I/O params&gt;

OUTDEF    &lt;job-id&gt;&lt;I/O params&gt;

These commands allow the user to specify the parameters necessary to
send input or retrieve output.  This command specifies how the data will
be transferred and specifies format, etc.

CANCEL &lt;job-id&gt;

This command allows a job to be cancelled from the RJE job stream.

STATUS &lt;status arg&gt;

status arg ::= &lt;empty&gt;|&lt;user id&gt;|&lt;job-id&gt;|&lt;job-id&gt;&lt;blank&gt;&lt;job-file-id&gt;

This command allows the user to determine the status of the RJE session,
all jobs under his usercode, a specific job, or the output of a specific
job.






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ALTER &lt;job-id&gt;&lt;site specific option&gt;

SITE &lt;site specific option&gt;

These commands allow site specific commands to be passed to the Server
RJE system.  The ALTER command is intended to effect specific jobs,
while the SITE command is used for commands of more global effect.  They
could be merged into one.

OP &lt;operator message&gt;

This command allows messages to be sent to the operator at the Server
site.

Reply Codes for the Proposed NETRJE
-----------------------------------

The reply codes for this protocol will follow the model proposed for the
new FTP specificaton in <a href="./rfc640">RFC 640</a>.  As a reminder we insert the pertinent
information from that RFC:

There are five values for the first digit of the reply code:

1yz     Positive Preliminary reply

   The requested action is being initiated; expect another reply before
   proceeding with a new command.  (The user-process sending another
   command before the completion reply would be in violation of
   protocol; but server-FTP processes should queue any commands that
   arrive while a preceding command is in progress.)  For
   implementations where simultaneous monitoring is difficult, this type
   of reply can be used to indicate that the command was accepted and
   the user-process may now pay attention to the data connections.

2yz     Positive Completion reply

   The requested action has been successfully completed.  A new request
   may be initiated.

3yz     Positive Intermediate reply

   The command has been accepted, but the requested action is being held
   in abeyance, pending receipt of further information.  The user should
   send another command specifying this information.  This reply is used
   in command sequence groups.







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4yz     Transient Negative Completion reply

   The command was not accepted and the requested action did not take
   place, but the error condition is temporary and the action may be
   requested again.  The user should return to the beginning of the
   command sequence, if any.  It is difficult to assign a meaning to
   "transient", particularly when two distinct sites (Server and
   User-processes) have to agree on the interpretation.  Each reply in
   the 4yz category might have a slightly different time value, but the
   intent is that the user-process is encouraged to try again.  A rule
   of thumb in determining if a reply fits into the 4yz or the 5yz
   (Permanent Negative) category is that replies are 4yz if the commands
   can be repeated without any change in command form or in properties
   of the User or Server (e.g., the command is spelled the same with the
   same arguments used, the user does not change his file access or user
   name, the server does not put up a new implementation.)

5yz     Permanent Negative Completion reply

   The command was not accepted and the requested action did not take
   place.  The User-process is discouraged from repeating the exact
   request (in the same sequence).  Even some "permanent" error
   conditions can be corrected, so the human user may want to direct his
   User-process to reinitiate the command sequence by direct action at
   some point in the future (e.g., after the spelling has been changed,
   or the user has altered his directory status.)

The following function groupings are encoded in the second digit:

x0z     Syntax - These replies refer to syntax errors, syntactically
correct commands that don't fit any functional category, and
unimplemented or superfluous commands.

x1z     Information - These are replies to requests for information,
such as status or help.

x2z     Connection - Replies referring to the Telnet and data
connections.

x3z     Authentication and accounting - Replies for the logon process
and accountng procedures.

x4z     Unspecified as yet.

x5z     File system - These replies indicate the status of the Server
file system vis-a-vis the requested transfer or other file system
action.





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The third digit gives a finer gradation of meaning in each of the
function categories specified by the second digit.  The list of replies
below will illustrate this.  Note that the text associated with each
reply is suggestive, rather than mandatory, and may even change
according to the command with which it is associated.  The reply codes,
on the other hand, should strictly follow the specifications.  That is,
Server implementations should not invent new codes for situations that
are only slightly different from the ones described here, but rather
should adapt codes already defined.

Below is a list of replies ordered by reply code.  Some new replies have
been added for RJE; these are marked by asterisks to aid the reader.
Following this list is a list of commands with the replies that are
possible for that command.  This list is not considered complete or
final; as usual comments are welcomed.

<span class="h2"><a class="selflink" id="section-110" href="#section-110">110</a> Restart marker reply,</span>

   In this case the text is exact and not left to the particular
   implementation; it must read:

      MARK yyyy = mmmm

   where yyyy is user-process data stream marker, and mmmm is Server's
   equivalent marker.  (Note the spaces between the markers and "=".)

<span class="h2"><a class="selflink" id="section-120" href="#section-120">120</a> Service ready in nnn minutes</span>

<span class="h2"><a class="selflink" id="section-125" href="#section-125">125</a> Data connection already open; transfer starting</span>

<span class="h2"><a class="selflink" id="section-150" href="#section-150">150</a> File status okay; about to open data connection</span>

<span class="h2"><a class="selflink" id="section-200" href="#section-200">200</a> Command okay</span>

<span class="h2"><a class="selflink" id="section-202" href="#section-202">202</a> Command not implemented, superfluous at this site</span>

<span class="h2"><a class="selflink" id="section-211" href="#section-211">211</a> System status, or system help reply</span>

<span class="h2"><a class="selflink" id="section-212" href="#section-212">212</a> Directory status</span>

<span class="h2"><a class="selflink" id="section-213" href="#section-213">213</a> File status</span>

<span class="h2"><a class="selflink" id="section-214" href="#section-214">214</a> Help message (on how to use the server or the meaning of a</span>
particular non-standard command.  This reply is useful only to the human
user.)

*215 RJE general status reply





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*216 job status reply

*217 RJE user's jobs status reply

<span class="h2"><a class="selflink" id="section-220" href="#section-220">220</a> Service ready for new user</span>

<span class="h2"><a class="selflink" id="section-221" href="#section-221">221</a> Service closing TELNET connecton (logged off if appropriate)</span>

<span class="h2"><a class="selflink" id="section-225" href="#section-225">225</a> Data connection open; no transfer in progress</span>

<span class="h2"><a class="selflink" id="section-226" href="#section-226">226</a> Closing data connection; requested file action successful (for</span>
example, file transfer or file abort.)

<span class="h2"><a class="selflink" id="section-227" href="#section-227">227</a> Entering [passive, active] mode</span>

<span class="h2"><a class="selflink" id="section-230" href="#section-230">230</a> User logged in</span>

<span class="h2"><a class="selflink" id="section-250" href="#section-250">250</a> Requested file action okay, completed</span>

*260 Job &lt;job-id&gt; has completed

*261 Output ready.  Type an empty line when ready

*262 Job &lt;job-id&gt; IS ALLOCATED  pathname

*263 Job &lt;job-id&gt; cancelled as requested

*264 Job &lt;job-id&gt; altered as requested to state status

<span class="h2"><a class="selflink" id="section-331" href="#section-331">331</a> User name okay, need password</span>

<span class="h2"><a class="selflink" id="section-332" href="#section-332">332</a> Need account for login</span>

<span class="h2"><a class="selflink" id="section-350" href="#section-350">350</a> Requested file action held in abeyance, pending further information</span>

<span class="h2"><a class="selflink" id="section-354" href="#section-354">354</a> Start mail input; end with CRLF, CRLF</span>

*360 Job &lt;job-id&gt; successfully submitted

<span class="h2"><a class="selflink" id="section-421" href="#section-421">421</a> Service not available, closing Telnet connecton.  </span>(This may be a
reply to any command if the service knows it must shut down.)

<span class="h2"><a class="selflink" id="section-425" href="#section-425">425</a> Can't open data connection</span>

<span class="h2"><a class="selflink" id="section-426" href="#section-426">426</a> Connection trouble, closed; transfer aborted</span>







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An RJE Protocol for a Resource Sharing Network



<span class="h2"><a class="selflink" id="section-450" href="#section-450">450</a> Requested file action not taken; file unavailable (e.g., file not</span>
found, no access)

<span class="h2"><a class="selflink" id="section-451" href="#section-451">451</a> Requested action aborted; local error in processing</span>

<span class="h2"><a class="selflink" id="section-452" href="#section-452">452</a> Requested action not taken:  </span>insufficient storage space in system

<span class="h2"><a class="selflink" id="section-500" href="#section-500">500</a> Syntax error, command unrecognized  </span>(This may include errors such as
command line too long.)

<span class="h2"><a class="selflink" id="section-501" href="#section-501">501</a> Syntax error in parameters or arguments</span>

<span class="h2"><a class="selflink" id="section-502" href="#section-502">502</a> Command not implemented</span>

<span class="h2"><a class="selflink" id="section-503" href="#section-503">503</a> Bad sequence of commands</span>

<span class="h2"><a class="selflink" id="section-504" href="#section-504">504</a> Command not implemented for that parameter</span>

<span class="h2"><a class="selflink" id="section-530" href="#section-530">530</a> Not logged in</span>

<span class="h2"><a class="selflink" id="section-532" href="#section-532">532</a> Need account for storing files</span>

<span class="h2"><a class="selflink" id="section-550" href="#section-550">550</a> Requested action not taken: file unavailable (e.g., file busy)</span>

<span class="h2"><a class="selflink" id="section-552" href="#section-552">552</a> Requested file action aborted:  </span>exceeded storage allocation for
current directory or dataset)

<span class="h2"><a class="selflink" id="section-553" href="#section-553">553</a> Requested action not taken:  </span>file name not allowed

*563 Job &lt;job-id&gt; is not known to the system

*564 Requested alteration is not permitted for the specified job.

Reply codes for RJE

   USER

      230

      530

      500, 501, 421

      331, 332

   PASS






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      230

      202

      530

      500, 501, 503, 421

      332

   ACCT

      230

      202

      530

      500, 501, 503, 421

   BYE

      221

      500

   REINIT

      120

      220

      220

      421

      500, 502

   ABORT

      225, 226

      500, 501, 502, 421

   STATUS

      211, 212, 213





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      450

      500, 501, 502, 421, 530

   HELP

      211, 214

      500, 501, 502, 421

   SOCK

      200

      500, 501, 421, 530

   BYTE, MODE, TYPE, STRU

      200

      500, 501, 504, 421, 530

   SCHED

      360     JOB &lt;job-id&gt; successfully submitted

      260     Job &lt;job-id&gt; has completed.

      125          500

      425, 426     501

      226          504, 532

   OUTPUT

      261     Output ready.  Type an empty line when ready.

      125     Transfer started

      226          500

      425, 426      501

      110

   OUTDEF





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      225     Data connection opened, no transfer in progress.

      425          500

                   501

                   504

   INDEF

      225          500

      425          501

                   504

   INPATH/OUTPATH

      262     JOB &lt;job-id&gt; IS ALLOCATED PATHNAME &gt;

                   500     504

                    501

   DISCARD

                 250     500     530

                 450     501

                 550     502

                         421

   CANCEL

      263     Job &lt;job-id&gt; Cancelled as requested

                    500     504

                    501

                    502

      563     Job &lt;job-id&gt; is not known to the system







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An RJE Protocol for a Resource Sharing Network



      564     Requested Alteration is not permitted for the specific
      job.

   STATUS

      215     RJE general status reply

      216     RJE job status reply

      217     RJE user's jobs status reply

      500, 501, 502, 504

   ALTER



      264     Job &lt;job-id&gt; altered as requested to state status

      500, 501, 502, 504     563, 564

   SITE

      200

      500, 501, 502, 504

   OP

      200

      500, 501, 502, 504




















                                                               [page 23]</pre>
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An RJE Protocol for a Resource Sharing Network



References
----------

Braden, R.

   1971 "Interim NETRJS Specifications", <a href="./rfc189">RFC 189</a>, NIC 7133.

Bressler, R.; Guida, R.; and McKenzie, A.

   1972 "Remote Job Entry Protocol", <a href="./rfc407">RFC 407</a>

Neigus, N.

   1973 "The File Transfer Protocol", <a href="./rfc542">RFC 542</a>.

Neigus, N.; Pogran, K.; and Postel, J.

   1974 "A New Schema for FTP Reply Codes", <a href="./rfc640">RFC 640</a>.


































                                                               [page 24]</pre>
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An RJE Protocol for a Resource Sharing Network



Figures
-------

   +-----------+
   !           !
   !  user     !
   !  RJE      !
   ! interface !
   !           !
   +-----------+     +--------+    Telnet Connection     +--------+
         !           !        !                          !        !
         !           ! user   !-------------------------&gt;! server !
         ------------! RJE    !                          ! RJE    !
                     ! module !&lt;-------------------------! module !
                     !        !                          !        !
                     +--------+                          +--------+

      all RJE commands, replies and data on telnet connection


                         RJE Using Only Telnet

                                 Figure 1.

   +-----------+
   !  user     !
   !  RJE      !
   ! interface !
   +-----------+     +--------+     Telnet Connection      +--------+
         !           ! user   !---------------------------&gt;! server !
         ------------! RJE    !  RJE Commands and Replies  ! RJE    !
                     ! module !&lt;---------------------------! module !
                     +--------+                            +--------+
                         !                                     !
                     +--------+                            +--------+
                     ! data   !          RJE Data          ! data   !
                     !transfer!----------------------------!transfer!
                     +--------+                            +--------+
                        !                                      !
           User's Local File System                  Server's RJE System
           Card Readers or Line Printers

                 RJE Using a Separate Data Connection

                                 Figure 2.







                                                               [page 25]</pre>
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An RJE Protocol for a Resource Sharing Network



   +-----------+
   !  user     !
   !  RJE      !
   ! interface !
   +-----------+     +--------+     Telnet Connection      +--------+
         !           ! user   !---------------------------&gt;! server !
         ------------! RJE    !  RJE Commands and Replies  ! RJE    !
                     ! module !&lt;---------------------------! module !
                     +--------+                            +--------+

                        ! !
                     +--------+     Telnet Connection      +--------+
                     ! user   !---------------------------&gt;! server !
                     ! FTP    !  FTP Commands and Replies  ! FTP    !
                     ! module !&lt;---------------------------! module !
                     +--------+                            +--------+

                         !                                     !
                     +--------+                            +--------+
                     ! data   !          RJE Data          ! data   !
                     !transfer!----------------------------!transfer!
                     +--------+                            +--------+
                        !                                      !
           User's Local File System                  Server's File
   System
           Card Readers or Line Printers

                               RJE Using FTP

                                 Figure 3.






















                                                               [page 26]
</pre>