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RFC 0740

NETRJS Protocol

Pages: 19
Historic
Obsoletes:  0599

ToP   noToC   RFC0740 - Page 1
Network Working Group                                          R. Braden
Request for Comments: 740                                       UCLA-CCN
NIC: 42423                                              22 November 1977
Obsoletes: 189, 599



                            NETRJS PROTOCOL




A.  Introduction

   NETRJS, a private protocol for remote job entry service, was defined
   and implemented by the UCLA Campus Computing Network (CCN) for batch
   job submission to an IBM 360 Model 91. CCN's NETRJS server allows a
   remote user, or a daemon process working in behalf of a user, to
   access CCN's RJS ("Remote Job Service") subsystem.  RJS provides
   remote job entry service to real remote batch (card reader/line
   printer) terminals over direct communications lines as well as to the
   ARPANET.

   A batch user at a remote host needs a NETRJS user process to
   communicate with the NETRJS server at the batch host. An active
   NETRJS user process simulates a "Virtual Remote Batch Terminal", or
   "VRBT".

   A VRBT may have virtual card readers, printers, and punches. In
   addition, every VRBT has a virtual remote operator console. Using a
   virtual card reader, a Network user can transmit a stream of card
   images comprising one or more batch jobs, complete with job control
   language ("JCL"), to the batch server host. The NETRJS server will
   cause these jobs to be spooled into the batch system to be executed
   according to their priority.  NETRJS will automatically return the
   print and/or punch output images which are created by these jobs to
   the virtual printer and/or card punch at the VRBT from which the job
   was submitted. The batch user can wait for his output, or he can
   signoff and signon again later to receive it.

   To initiate  a NETRJS session, the user process must execute a
   standard ICP to a fixed socket at the server.  The result is to
   establish a full-duplex Telnet connection for the virtual remote
   operator console, allowing the VRBT to signon to RJS.  The virtual
   remote operator console can then be used to issue commands to NETRJS
   and to receive status, confirmation, and error messages from the
ToP   noToC   RFC0740 - Page 2
   server.  The most important remote operator commands are summarized
   in Appendix D.

   Different VRBT's are distinguished by 8-character terminal id's,
   which are assigned by the server site to individual batch users or
   user groups.

B.  Connections and Protocols

   The protocol uses up to five connections between the user and server
   processes.  The operator console uses a a full-duplex Telnet
   connection. The data transfer streams for the virtual card reader,
   printer, and punch each use a separate simplex connection under a
   data transfer protocol defined in Appendix A. This document will use
   the term "channel" for one of these simplex data transfer connections
   and will designate a connection "input" or "output" with reference to
   the server.

   A particular data transfer channel needs to be open only while it is
   in use, and different channels may be used sequentially or
   simultaneously. CCN's NETRJS server will support simultaneous
   operation of a virtual card reader, a virtual printer, and a virtual
   punch (in addition to the operator console) on the same VRBT process.
   The NETRJS protocol could easily be extended to any number of
   simultaneously-operating virtual card readers, printers, and punches.

   The NETRJS server takes a passive role in opening the data channels:
   the server only "listens" for an RFC from the user process. NETRJS is
   defined with an 8-bit byte size on all data channels.

   Some implementations of NETRJS user processes are daemons, operating
   as background processes to submit jobs from a list of user requests;
   other implementations are interactive processes executed directly
   under terminal control by remote users. In the latter case, the VRBT
   process generally multiplexes the user terminal between NETRJS, i.e.,
   acting as the remote operator console, and entering local commands to
   control the VRBT. Local VRBT commands allow selection of the files
   containing job streams to be sent to the server as well as files to
   receive job output from the server.  Other local commands would cause
   the VRBT to open data transfer channels to the NETRJS server and to
   close these channels to free buffer space or abort transmission.

   The user process has a choice of three ICP sockets, to select the
   character set of the VRBT -- ASCII-68, ASCII-63, or EBCDIC. The
   server will make the corresponding translation of the data in the
   card reader and printer channels. (In the CCN implementation of
   NETRJS, an EBCDIC VRBT will transmit and receive, without
ToP   noToC   RFC0740 - Page 3
   translation, "transparent" streams of 8-bit bytes, since CCN is an
   EBCDIC installation). The punch stream will always be transparent,
   outputting "binary decks"  of 80-byte records untranslated. The
   operator console connections always use Network ASCII, as defined by
   the Telnet protocol.

   The NETRJS protocol provides data compression, replacing repeated
   blanks or other characters by repeat counts.  However, when the
   terminal id is assigned, a particular network VRBT may be specified
   to use no data compression.  In this case, NETRJS will simply
   truncate trailing blanks and send records in a simple "op
   code-length-data" form, called "truncated format" (see Appendix A).

C.  Starting and Terminating a Session

   The remote user establishes a connection to the NETRJS server by
   executing an ICP to the contact socket 71 (decimal) for EBCDIC,
   socket 73 (decimal) for ASCII-68, or to socket 75 (decimal) for
   ASCII-63. A successful ICP results in a pair of connections which are
   in fact the NETRJS operator console connections. NETRJS will send a
   READY message over the operator output connection.

   The user (process) must now enter a valid NETRJS signon command
   ("SIGNON terminal-id") through the virtual remote operator console.
   RJS will normally acknowledge signon with a console message; however,
   if there is no available NETRJS server port, NETRJS will indicate
   refusal by closing both operator connections.  If the user fails to
   enter a valid signon within 3 minutes, NETRJS will close the operator
   connections. If the VRBT attempts to open data transfer channels
   before the signon command is accepted, the data transfer channels
   will be refused  with an error message to the VRBT operator console.

   Suppose that S is the even number sent in the ICP; then the NETRJS
   connections have sockets at the server with fixed relation to S, as
   shown in the following table:

   Channel                          Server Socket     User Socket
   -------                          -------------     -----------
   Remote Operator Console Input         S            U + 3 Telnet
   Remote Operator Console Output        S + 1        U + 2 Telnet
   Data Transfer - Card Reader #1        S + 2        any odd number
   Data Transfer - Printer #1            S + 3        any even number
   Data Transfer - Punch #1              S + 5        any even number

   Once the VRBT has issued a valid signon, it can open data transfer
   channels and initiate input and output operations as explained in the
   following sections.  To terminate the session, the VRBT may close all
ToP   noToC   RFC0740 - Page 4
   connections.  Alternatively, it may enter a SIGNOFF command through
   the virtual remote operator console.  Receiving a SIGNOFF, NETRJS
   will wait until the current job output streams are complete and then
   itself terminate the session by closing all connections.

D.  Input Operations

   A job stream for submission to the NETRJS server is a series of
   logical records, each of which is a card image of at most 80
   characters. The user can submit a "stack" of successive jobs through
   the card reader channel with no end-of-job indication between jobs;
   NETRJS is able to parse the JCL sufficiently to recognize the
   beginning of each job.

   To submit a batch job or stack of jobs for execution, the user
   process must first open the card reader channel by issuing an Init
   for foreign socket S+2 and the appropriate local socket. NETRJS,
   which is listening on socket S+2, will return an RTS command to open
   the channel. When the channel is open, the user can begin sending his
   job stream using the protocol defined in Apendix A.  For each job
   successfully spooled, NETRJS will send a confirming message to the
   remote operator console.

   At the end of the job stack, the user process must send an
   End-of-Data transaction to initiate processing of the last job.
   NETRJS will then close the channel (to avoid holding buffer space
   unnecessarily).  At any time during the session, the user process can
   re-open the card reader channel and transmit another job stack.  It
   can also terminate the session and signon later to get the output.

   If the user process leaves the channel open for 5 minutes without
   sending any bits, the server will abort (close) the channel. The user
   process can abort the card reader channel at any time by closing the
   channel;  NETRJS will then discard the last partially spooled job.
   If NETRJS finds an error (e.g., transaction sequence number error or
   a dropped bit), it will abort the channel by closing the channel
   prematurely, and also inform the user process that the job was
   discarded (thus solving the race condition between End-of-Data and
   aborting).  The user process should retransmit only those jobs in the
   stack that have not been completely spooled.

   If the user's process, NCP, or host, or the Network itself fails
   during input, RJS will discard the job being transmitted.  A message
   informing the user that this job was discarded will be generated and
   sent to him the next time he signs on.  On the other hand, those jobs
   whose receipt have been acknowledged on the operator's console will
   not be affected by the failure, but will be executed by the server.
ToP   noToC   RFC0740 - Page 5
E.  Output Operations

   The VRBT may wait to set up a virtual printer or punch and open its
   channel until a STATUS message from NETRJS indicates output is ready;
   or it may leave the output channel(s) open during the entire session,
   ready to receive output whenever it becomes available.  The VRBT can
   also control which one of several available jobs is to be returned by
   entering appropriate operator commands.

   To be prepared to receive printer (or punch) output from its jobs,
   the VRBT issues an Init for foreign socket S+3 or S+5 for printer or
   punch output, respectively. NETRJS is listening on these sockets and
   should immediately return an STR.  However, it is possible that
   because of a buffer shortage, NETRJS will refuse the connection by
   returning a CLS; in this case, try again later.

   When NETRJS has job output for a particular virtual terminal and a
   corresponding open output channel, it will send the output as a
   series of logical records using the protocol in Appendix A.  The
   first record will consist of the job name (8 characters) followed by
   a comma and then the ID string from the JOB card, if any.  In the
   printer stream, the first column of each record after the first will
   be an ASA carriage control character (see Appendix C). A virtual
   printer in NETRJS has 254 columns, exclusive of carriage control;
   NETRJS will send up to 255 characters of a logical record it finds in
   a SYSOUT data set.  If the user wishes to reject or fold records
   longer than some smaller record size, he can do so in his VRBT
   process.

   NETRJS will send an End-of-Data transaction and then close an output
   channel at the end of the output for each complete batch job; the
   remote site must then send a new RFC to start output for another job.
   This gives the remote site a chance to allocate a new file for each
   job without breaking the output within a job.

   If the batch user wants to cancel (or backspace or defer) the output
   of a particular job, he can enter appropriate NETRJS commands on the
   operator input channel (see Appendix D).

   If NETRJS encounters a permanent I/O error in reading the disk data
   set, it will notify the user via his console, skip forward to the
   next set of system messages or SYSOUT data set in the same job, and
   continue. If the user process stops accepting bits for 5 minutes, the
   server will abort the channel. In any case, the user will receive
   notification of termination of output data transfer for each job via
   a remote console message.
ToP   noToC   RFC0740 - Page 6
   If the user detects an error in the stream, he can issue a Backspace
   (BSP) command from his console to repeat the last "page" of output,
   or a Restart (RST) command to repeat from the last SYSOUT data set or
   the beginning of the job, or he can abort the channel by closing his
   socket.  If he aborts the channel, NETRJS will simulate a Backspace
   command, and when the user re-opens the channel the job will begin
   transmission again from an earlier point in the same data set.  This
   is true even if the user terminates the current session first and
   reopens the channnel in a later session; RJS saves the state of every
   incomplete output stream.  However, before re-opening the channel he
   can defer this job for later output, restart it at the beginning, or
   cancel its output (see Appendix D).  Note that aborting the channel
   is only effective if NETRJS has not yet sent the End-of-Data
   transaction.

   If the user's process, NCP, or host or the Network itself fails
   during an output operation, NETRJS will act as if the channel had
   been aborted and the user signed off. NETRJS will discard the output
   of a job only after receiving the RFNM from the last data transfer
   message (containing an End-of-Data).  In no case should a NETRJS user
   lose output from a batch job.
ToP   noToC   RFC0740 - Page 7
                               APPENDIX A

                    Data Transfer Protocol in NETRJS

   1.  Introduction

      The records in the data transfer channels (for virtual card
      reader, printer, and punch) are generally grouped into
      transactions preceded by headers.  The transaction header includes
      a sequence number and the length of the transaction.  Network byte
      size must be 8 bits in these data streams.

      A transaction is the unit of buffering within the server software,
      and is limited to 880 8-bit bytes. Transactions can be as short as
      one record; however, those sites which are concerned with
      efficiency should send transactions as close as possible to the
      880 byte limit.

      There is no necessary connection between physical message
      boundaries and transactions ("logical messages"); the NCP can
      break a transaction arbitrarily into physical messages. The CCN
      server starts each transaction at the beginning of a new physical
      message, but this is not a requirement of the protocol.

      Each logical record within a transaction begins with an "op code"
      byte which contains the channel identification, so its value is
      unique to each channel but constant within a channel.  This choice
      provides the receiver with a convenient way to verify
      bit-synchronization, and it also allows an extension in the future
      to true "multi-leaving" (i.e., multiplexing all channels within
      one connection in each direction).

      The only provisions for transmission error detection in the
      current NETRJS protocol are (1) the "op code" byte to verify bit
      synchronization and (2) the transaction sequence number. Under the
      NETRJS protocol, a data transfer error must abort the entire
      transmission; there is no provision for restart.
ToP   noToC   RFC0740 - Page 8
   2.  Meta-Notation

      The following description of the NETRJS data transfer protocol
      uses a formal notation derived from that proposed in RFC 31 by
      Bobrow and Sutherland. The notation consists of a series of
      productions for bit string variables. Each variable name which
      represents a fixed length field is followed by the length in bits
      (e.g., SEQNUMB(16)).  Numbers enclosed in quotes are decimal,
      unless qualified by a leading X meaning hex.  Since each hex digit
      is 4 bits, the length is not shown explicitly in hex numbers.  For
      example, '255'(8) and X'FF' both represent a string of 8 one bits.

      The meta-syntactic operators are:

         |     :alternative string

         [ ]   :optional string

         ( )   :grouping

         +     :catenation of bit strings

      The numerical value of a bit string (interpreted as an integer) is
      symbolized by a lower case identifier preceding the string
      expression and separated by a colon.  For example, in
      "i:FIELD(8)", i symbolizes the numeric value of the 8 bit string
      FIELD.

      Finally, we use Bobrow and Sutherland's symbolism for iteration of
      a sub-string:  (STRING-EXPRESSION = n); denotes n occurrences of
      STRING-EXPRESSION, implicitly catenated together.  Here any n
      greater or equal to 0 is assumed unless n is explicitly
      restricted.

   3.  Protocol Definition

      STREAM ::= (TRANSACTION = n) + [END-OF-DATA]

         That is, STREAM, the entire sequence of data on a particular
         open channel, is a sequence of n TRANSACTIONS followed by an
         END-OF-DATA marker (omitted if the sender aborts the channel).

      TRANSACTION ::= THEAD(72) + (RECORD = r) + ('0'(1) = f)

         That is, a transaction consists of a 72 bit header, r records,
         and f filler bits; it may not exceed 880*8 bits.
ToP   noToC   RFC0740 - Page 9
      THEAD ::= X'FF'+f:FILLER(8)+SEQNUMB(16)+LENGTH(32)+X'00'

         Transactions are to be consecutively numbered in the SEQNUMB
         field, starting with 0 in the first transaction after the
         channel is (re-) opened.  The 32 bit LENGTH field gives the
         total length in bits of the r RECORD's which follow.  For
         convenience, the using site may add f additional filler bits at
         the end of the transaction to reach a convenient word boundary
         on his machine; the value f is transmitted in the FILLER field
         of THEAD.

      RECORD ::= COMPRESSED | TRUNCATED

         RJS will accept intermixed RECORD's which are COMPRESSED or
         TRUNCATED in an input stream.  RJS will send one or the other
         format in the printer and punch streams to a given VRBT; the
         choice is determined for each terminal id.

      COMPRESSED ::= '2'(2) + DEVID(6) + (STRING = p) + '0'(8)

      STRING     ::= ('6'(3) + i:DUPCOUNT(5))  |

         This form represents a string of i consecutive blanks

                     ('7'(3) + i:DUPCOUNT(5) + TEXTBYTE(8)) |

         This form represents string of i consecutive duplicates of
         TEXTBYTE.

                     ('2'(2) + j:LENGTH(6) + (TEXTBYTE(8) = j))

         This form represents a string of j characters.

      TRUNCATED  ::= '3'(2) + DEVID(6) + n:COUNT(8) + (TEXTBYTE(8)=n)

      DEVID(6)   ::= DEVNO(3) + t:DEVTYPE(3)

         DEVID identifies a particular virtual device, i.e., it
         identifies a channel.  DEVTYPE specifies the type of device, as
         follows:

            t = 1:  Output to remote operator console
                2:  Input from remote operator console
                3:  Input from card reader
                4:  Output to printer
                5:  Output to card punch
              6,7:  Unused
ToP   noToC   RFC0740 - Page 10
         DEVNO identifies the particular device of type t at this remote
         site; at present only DEVNO = 0 is possible.

      END-OF-DATA ::=X'FE'

         Signals end of job (output) or job stack (input).
ToP   noToC   RFC0740 - Page 11
                               APPENDIX B

                    Telnet for VRBT Operator Console

   The remote operator console connections use the ASCII Telnet
   protocol. Specifically:

      1.  The following one-to-one character mappings are used for the
      three EBCDIC graphics not in ASCII:

         ASCII in Telnet     |  NETRJS
         ----------------------------------------------------
         broken vertical bar |  solid vertical bar
         tilde               |  not sign
         back slash          |  cent sign

      2.  Telnet controls are ignored.

      3.  An operator console input line which exceeds 133 characters
      (exclusive of CR LF) is truncated by NETRJS.

      4.  NETRJS accepts BS (Control-H) to delete a character and CAN
      (Control-X) to delete the current line.  The sequence CR LF
      terminates each input and output line.  HT (Control-I) is
      translated to a single space. An ETX (Control-C) terminates
      (aborts) the session.  All other ASCII control characters are
      ignored.

      5.  NETRJS translates the six ASCII graphics with no equivalent in
      EBCDIC into the character question mark ("?") on input.
ToP   noToC   RFC0740 - Page 12
                               APPENDIX C

                            Carriage Control

   The carriage control characters sent in a printer channel by NETRJS
   conform to IBM's extended USASI code, defined by the following table:

      CODE       ACTION BEFORE WRITING RECORD
      ----       ----------------------------
      Blank      Space one line before printing
      0          Space two lines before printing
      -          Space three lines before printing
      +          Suppress space before printing
      1          Skip to channel 1
      2          Skip to channel 2
      3          Skip to channel 3
      4          Skip to channel 4
      5          Skip to channel 5
      6          Skip to channel 6
      7          Skip to channel 7
      8          Skip to channel 8
      9          Skip to channel 9
      A          Skip to channel 10
      B          Skip to channel 11
      C          Skip to channel 12
ToP   noToC   RFC0740 - Page 13
                               APPENDIX D

                      Network/RJS Command Summary

   This section presents an overview of the RJS Operator Commands, for
   the complete form and parameter specifications please see references
   2 and 3.

   Terminal Control and Information Commands

      SIGNON       First command of a session; identifies VRBT by giving
                   its terminal id.

      SIGNOFF      Last command of a session; RJS waits for any data
                   transfer in progress to complete and then closes all
                   connections.

      STATUS       Outputs on the remote operator console a complete
                   list, or a summary, of all jobs in the system for
                   this VRBT, with an indication of their processing
                   status in the batch host.

      ALERT        Outputs on the remote operator console an "Alert"
                   message, if any, from the computer operator.  The
                   Alert message is also automatically sent when the
                   user does a SIGNON, or whenever the message changes.

      MSG          Sends a message to the computer operator or to any
                   other RJS terminal (real or virtual).  A message from
                   the computer operator or another RJS terminal will
                   automatically appear on the remote operator console.

   Job Control and Routing Commands

      Under CCN's job management system, the default destination for
      output is the input source.  Thus, a job submitted under a given
      VRBT will be returned to that VRBT (i.e., the same terminal id),
      unless the user's JCL overrides the default destination.

      RJS places print and punch output destined for a particular remote
      terminal into either an Active Queue or a Deferred Queue.  When
      the user opens his print or punch output channel, RJS immediately
      starts sending job output from the Active Queue, and continues
      until this queue is empty.  Job output in the Deferred Queue, on
      the other hand, must be called for by job name, (via a RESET
      command from the remote operator)  before RJS will send it.  The
      Active/Deferred choice for output from a job is determined by the
ToP   noToC   RFC0740 - Page 14
      deferral status of the VRBT when the job is entered; the deferral
      status, which is set to the Active option when the user signs on,
      may be changed by the SET command.

      SET           Allows the remote user to change certain properties
                    of his VRBT for the duration of the current session;
      
                    (a)  May change the default output destination to be
                    another (real or virtual) RJS terminal or the
                    central facility.
      
                    (b)  May change the deferral status of the VRBT.

      DEFER         Moves the print and punch output for a specified job
                    or set of jobs from the Active Queue to the Deferred
                    Queue. If the job's output is in the process of
                    being transmitted over a channel, RJS aborts the
                    channel and saves the current output location before
                    moving the job to the Deferred Queue.  A subsequent
                    RESET command will return it to the Active Queue
                    with an implied Backspace (BSP).

      RESET         Moves specified job(s) from Deferred to Active Queue
                    so they may be sent to user.  A specific list of job
                    names or all jobs can be moved with one RESET
                    command.

      ROUTE         Re-routes output of specified jobs (or all jobs)
                    waiting in the Active and Deferred Queues for the
                    VRBT.  The new destination may be any other RJS
                    terminal or the central facility.

      ABORT         Cancels a job which was successfully submitted and
                    awaiting execution or is currently executing.

   Output Stream Control Commands

      BSP (BACKSPACE)  "Backspaces" output stream within current sysout
                    data set.  Actual amount backspaced depends upon
                    sysout blocking but is roughly equivalent to a page
                    on the line printer.

      CAN (CANCEL)  (a)  On an output channel, CAN causes the rest of
                    the output in the sysout data set currently being
                    transmitted to be omitted. Alternatively, may omit
                    the rest of the sysout data sets for the job
                    currently being transmitted; however, the remaining
ToP   noToC   RFC0740 - Page 15
                    system and accounting messages will be sent.
      
                    (b)  On an input channel, CAN causes RJS to ignore
                    the job currently being read.  However, the channel
                    is not aborted as a result, and RJS will continue
                    reading in jobs on the channel.
      
                    (c)  CAN can delete all sysout data sets for
                    specified job(s) waiting in Active or Deferred
                    Queue.

      RST (RESTART) (a)  Restarts a specified output stream at the
                    beginning of the current sysout data set or,
                    optionally, at the beginning of the job.
      
                    (b)  Marks as restarted specified job(s) whose
                    transmission was earlier interrupted by system
                    failure or user action (e.g., DEFER command or
                    aborting the channel).  When RJS transmits these
                    jobs again it will start at the beginning of the
                    partially transmitted sysout data set or,
                    optionally, at the beginning of the job. This
                    function may be applied to jobs in either the Active
                    or the Deferred Queue; however, if the job was in
                    the Deferred Queue then RST also moves it to the
                    Active Queue.  If the job was never transmitted, RST
                    has no effect other than this queue movement.

      REPEAT        Sends additional copies of the output of specified
                    jobs.

      EAM           Echoes the card reader stream back in the printer
                    and/or punch stream.
ToP   noToC   RFC0740 - Page 16
                               APPENDIX E

                        NETRJS TERMINAL OPTIONS

   When a new NETRJS virtual terminal is defined, certain options are
   available; these options are listed below.

      1. Truncated/Compressed Data Format

         A VRBT may use either the truncated data format (default) or
         the compressed format for printer and punch output.  See
         Reference 9 for discussion of the virtues of compression.

      2. Automatic Coldstart Job Resubmission

         If "R" (Restart) is specified in the accounting field on the
         JOB card and if this option is chosen, RJS will automatically
         resubmit the job from the beginning if the server operating
         system should be "coldstarted" before all output from the job
         is returned.  Otherwise, the job will be lost and must be
         resubmitted from the remote terminal in case of a coldstart.

      3. Automatic Output RESTART

         With this option, transmission of printer output which is
         interrupted by a broken connection always starts over at the
         beginning.  Without this option, the output is backspaced
         approximately one page when restarted, unless the user forces
         the output to start over from the beginning with a RESTART
         command when the printer channel is re-opened and before
         printing begins.

      4. Password Protection

         This option allows a password to be supplied when a terminal is
         signed on, preventing unauthorized use of the terminal ID.

      5. Suppression of Punch Separator and Large Letters.

         This option suppresses both separator cards which RJS normally
         puts in front of each punched output deck, and separator pages
         on printed output containing the job name in large block
         letters.  These separators are an operational aid when the
         ouptut is directed to a real printer or punch, but generally
         undesirable for an ARPA user who is saving the output in a file
         for on-line examination.
ToP   noToC   RFC0740 - Page 17
                               APPENDIX F

                  Character Translation by CCN Server

   A VRBT declares its character set for job input and output by the
   initial connection socket it chooses. A VRBT can have the ASCII-68,
   the ASCII-63, or the EBCDIC character set.  The ASCII-63 character
   mapping was added to NETRJS at the request of users whose terminals
   are equipped with keyboards like those found on the model 33
   Teletype.

   Since CCN operates an EBCDIC machine, its NETRJS server translates
   ASCII input to EBCDIC and translates printer output back to ASCII.
   The details of this translation are described in the following.

   For ASCII-68, the following rules are used:

      1.  There is one-to-one mapping between the three ASCII characters
          broken vertical bar, tilde, and back slash, which are not in
          EBCDIC, and the three EBCDIC characters vertical bar, not
          sign, and cent sign (respectively), which are not in ASCII.

      2.  The other six ASCII graphics not in EBCDIC are translated on
          input to unused EBCDIC codes, shown in the table below.

      3.  The ASCII control DC4 is mapped to and from the EBCDIC control
          TM.

      4.  The other EBCDIC characters not in ASCII are mapped in the
          printer stream into the ASCII question mark.

   For ASCII-63, the same rules are used except that the ASCII-63 codes
   X'60' and X'7B' - X'7E' are mapped as in the following table.

      EBCDIC              | ASCII-68 VRBT       | ASCII-63 VRBT
      ---------------------------------------------------------------
      vertical bar  X'4F' | vertical bar  X'7C' | open bracket  X'5B'
      not sign      X'5F' | tilde         X'7E' | close bracket X'5D'
      cent sign     X'4A' | back slash    X'5C' | back slash    X'5C'
      underscore    X'6D' | underscore    X'5F' | left arrow    X'5F'
      .             X'71' | up arrow      X'5E' | up arrow      X'5E'
      open bracket  X'AD' | open bracket  X'5B' | .             X'7C'
      close bracket X'BD' | close bracket X'5D' | .             X'7E'
      .             X'8B' | open brace    X'7B' | .             X'7B'
      .             X'9B' | close brace   X'7D' | .             X'7D'
      .             X'79' | accent        X'60' | .             X'60'
ToP   noToC   RFC0740 - Page 18
                               APPENDIX G

                               REFERENCES

   1. "Interim NETRJS Specifications", R. T. Braden.  RFC #189:  NIC
   #7133, July 15, 1971.

      This was the basic system programmer's definition document.  The
      proposed changes mentioned on the first page of RFC #189 were
      never implemented, since the DTP then in vogue became obsolete.

   2. "NETRJS Remote Operator Commands", R. T. Braden.  NIC #7182,
   August 9, 1971

      This document together with References 3 and 8 define the remote
      operator (i.e. user) command language for NETRJS, and form the
      basic user documentation for NETRJS at CCN.

   3. "Implementation of a Remote Job Service", V. Martin and T. W.
   Springer.  NIC #7183, July, 1971.

   4. "Remote Job Entry to CCN via UCLA Sigma 7; A scenario", UCLA/CCN.
   NIC #7748, November 15, 1971.

      This document described the first NETRJS user implementation
      available on a server host.  This program is no longer of general
      interest.

   5. "Using Network Remote Job Entry", E. F. Harslem.  RFC #307:  NIC
   #9258, February 24, 1972.

      This document is out of date, but describes generally the Tenex
      NETRJS user process "RJS".

   6. "EBCDIC/ASCII Mapping for Network RJS", R. T. Braden.  RFC #338:
   NIC #9931, May 17, 1972.

      The ASCII-63 mapping described here is no longer correct, but
      CCN's standard ASCII-68/EBCDIC mapping is described correctly.
      This information is accurately described in Appendix F of the
      current document.
ToP   noToC   RFC0740 - Page 19
   7. "NETRJT--Remote Job Service Protocol for TIP's", R. T. Braden. RFC
   #283: NIC 38165, December 20, 1971.

      This was an attempt to define an rje protocol to handle TIPs.
      Although NETRJT was never implemented, many of its features are
      incorporated in the current Network standard RJE protocol.

   8. "CCN NETRJS Server Messages to Remote User", R. T. Braden.  NIC
   #20268, November 26, 1973.

   9. "FTP Data Compression", R. T. Braden.  RFC #468:  NIC #14742,
   March 8, 1973.

   10. "Update on NETRJS", R. T. Braden.  RFC #599: NIC #20854, December
   13, 1973.

      This updated reference 1, the current document combines the two.

   11. "Network Remote Job Entry -- NETRJS", G. Hicks.  RFC #325: NIC
   9632, April 6, 1972.

   12. "CCNRJS: Remote Job Entry between Tenex and UCLA-CCN", D.
   Crocker.  NUTS Note 22, [ISI]<DOCUMENTATION>CCNRJS.DOC, March 5,
   1975.

   13. "Remote Job Service at UCSB", M. Krilanovich.  RFC #477: NIC
   #14992, May 23, 1973.