Subject: draft-ietf-tn5250e-02.txt

From: Jeffrey Stevens <[email-masked]>
Date: Wed, 6 May 1998 17:30:48 -0400

Hello Everyone,

This is a refreshed draft which includes a little reorganization
and more detail.  Some major changes include the following:

- Addition of password encryption negotiation
- Move description of NEW-ENVIRON from section 3. to section 4.
- Modify reference to Network Station to indicate it is a subset
  of 5250 devices (section 4)
- All hex dumps are now 8 bytes across (except for end-to-end example)
- Addition of printer pass-through header description (new figure)
- Addition of printer pass-through header example (new figure)
- Addition of end-to-end example of a printer datastream exchange
- Updates to Table of Contents

=============================================================
J.S. Stevens   AS/400 TCP/IP Applications (LPD/WSG/Telnet)
Work: [email-masked]     Private: [email-masked]

TN3270E Working Group                                     T. Murphy, Jr.
Internet Draft: <draft-ietf-tn5250e-02.txt>                     P. Rieth
Updates:  RFC 1205                                            J. Stevens
Expiration Date: August, 1998                            IBM Corporation
                                                           February 1998

                        5250 Telnet Enhancements

Status of this Memo

   This document is an Internet Draft.  Internet Drafts are working
   documents of the Internet Engineering Task Force (IETF), its Areas,
   and its Working Groups.  Note that other groups may also distribute
   working documents as Internet Drafts.

   Internet Drafts are draft documents valid for a maximum of six
   months.  Internet Drafts may be updated, replaced, or obsoleted by
   other documents at any time.  It is not appropriate to use Internet
   Drafts as reference material or to cite them other than as a "working
   draft" or "work in progress."

   Please check the I-D abstract listing contained in each Internet
   Draft directory to learn the current status of this or any Internet
   Draft.  Distribution of this document is unlimited.

Copyright Notice

   Copyright (C) The Internet Society (1998).  All Rights Reserved.

Abstract

   This draft describes the interface to the IBM 5250 Telnet server that
   allows client Telnet to request a Telnet terminal or printer session
   using a specific device name.  If a requested device name is not
   available, a method to retry the request using a new device name is
   described.  Methods to request specific Telnet session settings and
   auto-signon function are also described.

   By allowing a Telnet client to select the device name, the 5250
   Telnet server opens the door for applications to set and/or extract
   useful information about the Telnet client.  Some possibilities are
   1) selecting a customized device name associated with a particular
   user profile name for National Language Support or subsystem routing,
   2) connecting PC and network printers as clients and 3) auto-signon
   using clear-text or DES-encrypted password exchange.

Murphy, Rieth & Stevens                                         [Page 1]

Internet Draft          5250 Telnet Enhancements           February 1998

   Applications may need to use system API's on the AS/400 in order to
   extract Telnet session settings from the device name description.
   Refer to the Retrieve Device Description (QDCRDEVD) API described in
   the AS/400 System API book [3] on how to extract information using
   the DEVD0600 and DEVD1100 templates.

   This draft describes how the IBM 5250 Telnet server supports Work
   Station Function (WSF) printers using 5250 Display Station Pass-
   Through.  A response code is returned by the Telnet server to
   indicate success or failure of the WSF printer session.

Murphy, Rieth & Stevens                                         [Page 2]

Internet Draft          5250 Telnet Enhancements           February 1998

1. Table of Contents

                               CONTENTS

    1.  Table of Contents..................................   3
    2.  Enhancing Telnet Negotiations......................   4
    3.  Standard Telnet Option Negotiation.................   5
    4.  Enhanced Telnet Option Negotiation.................   7
    5.  Enhanced Display Emulation Support.................  10
    6.  Enhanced Display Auto-Signon and Password
        Encryption.........................................  11
    7.  Device Name Collision Processing...................  15
    8.  Enhanced Printer Emulation Support.................  16
    9.  Telnet Printer Terminal Types......................  18
   10.  Telnet Printer Startup Response Record for Printer
        Emulators..........................................  21
        10.1  Example of a Success Response Record.........  22
        10.2  Example of an Error Response Record..........  23
        10.3  Response Codes...............................  24
   11.  Printer Steady-State Pass-Through Interface........  25
        11.1  Example of a Print Record....................  28
        11.2  Example of a Print Complete Record...........  29
        11.3  Example of a Null Print Record...............  30
   12.  End-to-End Print Example...........................  31
   13.  Author's Note......................................  36
   14.  References.........................................  36
   15.  Security Considerations............................  37
   16.  Author's Address...................................  37
   17.  Relation to Other RFC's............................  38

                          LIST OF FIGURES

   Figure 1.  Example of a success status response
              record.......................................  22
   Figure 2.  Example of an error response record..........  23
   Figure 3.  Layout of the printer pass-through
              header.......................................  25
   Figure 4.  Server sending client data with a print
              record.......................................  28
   Figure 5.  Client sending server a print complete
              record.......................................  29
   Figure 6.  Server sending client a null print
              record.......................................  30

Murphy, Rieth & Stevens                                         [Page 3]

Internet Draft          5250 Telnet Enhancements           February 1998

2. Enhancing Telnet Negotiations

   The 5250 Telnet server enables clients to negotiate both terminal and
   printer device names through Telnet Environment Options Negotiations,
   defined in the Standards Track RFC 1572 [13].

   The purpose of RFC 1572 is to exchange environment information using
   a set of standard or custom variables.  By using a combination of
   both standard VAR's and custom USERVAR's, the 5250 Telnet server
   allows client Telnet to request a pre-defined specific device by
   name.

   If no pre-defined device exists then the device will be created, with
   client Telnet having the option to negotiate device attributes, such
   as the code page, character set, keyboard type, etc.

   Since printers can now be negotiated as a device name, new terminal
   types have been defined to request printers.  For example, you can
   now negotiate "IBM-3812-1" and "IBM-5553-B01" as valid TERMINAL-TYPE
   options [11].

   Finally, the 5250 Telnet server will allow exchange of user profile
   and password information, where the password may be in either clear-
   text or encrypted form.  If a valid combination of profile and
   password is received, then the client is allowed to bypass the sign-
   on panel.  The setting of the QRMTSIGN system value must be either
   *VERIFY or *SAMEPRF for the bypass of the sign-on panel to succeed.

Murphy, Rieth & Stevens                                         [Page 4]

Internet Draft          5250 Telnet Enhancements           February 1998

3. Standard Telnet Option Negotiation

   Telnet server option negotiation typically begins with the issuance,
   by the server, of an invitation to engage in terminal type
   negotiation with the Telnet client (DO TERMINAL-TYPE) [11].  The
   client and server then enter into a series of sub-negotiations to
   determine the level of terminal support that will be used.  After the
   terminal type is agreed upon, the client and server will normally
   negotiate a required set of additional options (EOR [12], BINARY
   [10], SGA [15]) that are required to support "transparent mode" or
   full screen 5250/3270 block mode support.  As soon as the required
   options have been negotiated, the server will suspend further
   negotiations, and begin with initializing the actual virtual device
   on the AS/400.  A typical exchange might start like the following:

   AS/400 Telnet server              Enhanced Telnet client
   --------------------------        -------------------------
   IAC DO TERMINAL-TYPE        -->
                               <--   IAC WILL TERMINAL-TYPE
   IAC SB TERMINAL-TYPE SEND
   IAC SE                      -->
                                     IAC SB TERMINAL-TYPE IS
                               <--   IBM-5555-C01 IAC SE
   IAC DO EOR                  -->
                               <--   IAC WILL EOR
                               <--   IAC DO EOR
   IAC WILL EOR                -->
                                .
                                .
   (other negotiations)         .

   Actual bytes transmitted in the above example are shown in hex below.

   AS/400 Telnet server              Enhanced Telnet client
   --------------------------        -------------------------
   FF FD 18                    -->
                               <--   FF FB 18
   FF FA 18 01 FF F0           -->
                                     FF FA 18 00 49 42 4D 2D
                                     35 35 35 35 2D 43 30 31
                               <--   FF F0
   FF FD 19                    -->
                               <--   FF FB 19
                               <--   FF FD 19
   FF FB 19                    -->
                                .
                                .
   (other negotiations)         .

Murphy, Rieth & Stevens                                         [Page 5]

Internet Draft          5250 Telnet Enhancements           February 1998

   Some negotiations are symmetrical between client and server and some
   are negotiated in one direction only.  Also, it is permissible and
   common practice to bundle more than one response or request, or
   combine a request with a response, so the actual exchange may look
   different in practice to what is shown above.

Murphy, Rieth & Stevens                                         [Page 6]

Internet Draft          5250 Telnet Enhancements           February 1998

4. Enhanced Telnet Option Negotiation

   In order to accommodate the new environment option negotiations, the
   server will bundle an environment option invitation along with the
   standard terminal type invitation request to the client.

   A client should either send a negative acknowledgment (WONT NEW-
   ENVIRON), or at some point after completing terminal type
   negotiations, but before completing the full set of negotiations
   required for transparent mode, engage in environment option sub-
   negotiation with the server.  A maximum or 1024 bytes of environment
   strings may be sent to the server.  A recommended sequence might look
   like the following:

   AS/400 Telnet server              Enhanced Telnet client
   --------------------------        -------------------------
   IAC DO NEW-ENVIRON
   IAC DO TERMINAL-TYPE        -->
   (2 requests bundled)
                               <--   IAC WILL NEW-ENVIRON
   IAC SB NEW-ENVIRON SEND
   VAR IAC SE                  -->
                                     IAC SB NEW-ENVIRON IS
                                     VAR "USER" VALUE "JONES"
                                     USERVAR "DEVNAME" VALUE "MYDEVICE07"
                               <--   IAC SE
                               <--   IAC WILL TERMINAL-TYPE
                                     (do the terminal type
                                     sequence first)
   IAC SB TERMINAL-TYPE SEND
   IAC SE                      -->
                                     IAC SB TERMINAL-TYPE IS
                               <--   IBM-5555-C01 IAC SE
                                     (terminal type negotiations
                                     completed)
   IAC DO EOR                  -->
   (server will continue
   with normal transparent
   mode negotiations)
                               <--   IAC WILL EOR
                                .
                                .
     (other negotiations)       .

   Actual bytes transmitted in the above example are shown in hex below.

Murphy, Rieth & Stevens                                         [Page 7]

Internet Draft          5250 Telnet Enhancements           February 1998

   AS/400 Telnet server              Enhanced Telnet client
   --------------------------        -------------------------
   FF FD 27
   FF FD 18                    -->
   (2 requests bundled)
                               <--   FF FB 27
   FF FA 27 01 00 FF F0        -->
                                     FF FA 27 00 00 55 53 45
                                     52 01 4A 4F 4E 45 53 03
                                     44 45 56 4E 41 4D 45 01
                                     4D 59 44 45 56 49 43 45
                               <--   30 37 FF F0
                               <--   FF FB 18
                                     (do the terminal type
                                     sequence first)
   FF FA 18 01 FF F0           -->
                                     FF FA 18 00 49 42 4D 2D
                                     35 35 35 35 2D 43 30 31
                               <--   FF F0
   FF FD 19                    -->
   (server will continue
   with normal transparent
   mode negotiations)
                               <--   FF FB 19
                                .
                                .
   (other negotiations)         .

   RFC 1572 defines 6 standard VAR's: USER, JOB, ACCT, PRINTER,
   SYSTEMTYPE, and DISPLAY.  The USER standard VAR will hold the value
   of the AS/400 user profile name to be used in auto-signon requests.
   The Telnet server will make no direct use of the additional 5 VAR's,
   nor are any of them required to be sent.  All standard VAR's and
   their values that are received by the Telnet server will be placed in
   a buffer, along with any USERVAR's received (described below), and
   made available to a registered initialization exit program to be used
   for any purpose desired.

   There are some reasons you may want to send NEW-ENVIRON negotiations
   prior to TERMINAL-TYPE negotiations.  With AS/400 TELNET server,
   several virtual device modes can be negotiated: 1) VTxxx device 2)
   3270 device 3) 5250 device (includes Network Station).  The virtual
   device mode selected depends on the TERMINAL-TYPE negotiated plus any
   other TELNET option negotiations necessary to support those modes.
   The AS/400 TELNET server will create the desired virtual device at
   the first opportunity it thinks it has all the requested attributes
   needed to create the device.  This can be as early as completion of
   the TERMINAL-TYPE negotiations.

Murphy, Rieth & Stevens                                         [Page 8]

Internet Draft          5250 Telnet Enhancements           February 1998

   For the case of Transparent mode (5250 device), then the moment
   TERMINAL-TYPE, BINARY, and EOR options are negotiated the TELNET
   server will go create the virtual device.  Receiving any NEW-ENVIRON
   negotiations after these option negotiations are complete will result
   in the NEW-ENVIRON negotiations having no effect on device
   attributes, as the virtual device will have already been created.
   So, for Transparent mode, NEW-ENVIRON negotiations are effectively
   closed once EOR is negotiated, since EOR is generally the last option
   done.

   For other devices modes (such as VTxxx or 3270), you cannot be sure
   when the AS/400 TELNET server thinks it has all the attributes to
   create the device.  Recall that NEW-ENVIRON negotiations are
   optional, and therefore the AS/400 TELNET server need not wait for
   any NEW-ENVIRON options prior to creating the virtual device.  It is
   in the clients best interest to send NEW-ENVIRON negotiations as soon
   as possible, preferably before TERMINAL-TYPE is negotiated.  That
   way, the client can be sure the requested attributes were received
   before the virtual device is created.

Murphy, Rieth & Stevens                                         [Page 9]

Internet Draft          5250 Telnet Enhancements           February 1998

5. Enhanced Display Emulation Support

   RFC 1572 style USERVAR variables have been defined to allow a
   compliant Telnet client more control over the Telnet server virtual
   device on the AS/400.  These USERVAR's allow the client Telnet to
   create or select a previously created virtual device.  If the virtual
   device does not exist and must be created, then the USERVAR variables
   are used to create and initialize the device attributes.  If the
   virtual device already exists, the device attributes are modified.

   The USERVAR's defined to accomplish this are:

   USERVAR    VALUE              EXAMPLE           DESCRIPTION
   --------   ----------------   ----------------  -------------------
   DEVNAME    us-ascii char(x)   MYDEVICE07        Display device name
   KBDTYPE    us-ascii char(3)   USB               Keyboard type
   CODEPAGE   us-ascii char(y)   437               Code page
   CHARSET    us-ascii char(y)   1212              Character set

   x - up to a maximum of 10 characters
   y - up to a maximum of 5 characters

   For a description of the KBDTYPE, CODEPAGE and CHARSET parameters and
   their permissible values, refer to Chapter 8 in the Communications
   Configuration Reference [5] and also to Appendix C in National
   Language Support [16].

Murphy, Rieth & Stevens                                        [Page 10]

Internet Draft          5250 Telnet Enhancements           February 1998

6. Enhanced Display Auto-Signon and Password Encryption

   Several 5250 Telnet server specific USERVAR's will be defined.  One
   will carry a random seed to be used in Data Encryption Standard (DES)
   password encryption, and another will carry the encrypted copy of the
   password.  This would use the same password/substitution scheme as
   APPC and Client Access.  For a description of the 7-step DES
   encryption scheme, refer to Federal Information Processing Standards
   Publication 46 [17] or visit the IBM Customer Support FTP Server at
   one of the following links:

   ftp://ftp.networking.ibm.com/pub/standards/ciw/sig/sec/pwsubciw.ps
   ftp://ftp.networking.ibm.com/pub/standards/ciw/sig/sec/pwsubciw.ps.Z
   ftp://ftp.networking.ibm.com/pub/standards/ciw/sig/sec/pwsubciw.zip

   If encrypted password exchange is not required, clear-text password
   exchange is permitted using the same USERVAR's defined for
   encryption.  For this case, the random client seed should be set to
   either an empty value (RFC 1572 preferred method) or to hexadecimal
   zeros to indicate the password is not encrypted, but is clear-text.

   It should be noted that security of clear-text password exchange
   cannot be guaranteed unless the network is physically protected or a
   trusted network (such as an intranet).  If your network is vulnerable
   to IP address spoofing or directly connected to the Internet, you
   should engage in encrypted password exchange to validate a clients
   identity.

   Additional VAR's and USERVAR's have also been defined to allow an
   auto-signon user greater control over their startup environment,
   similar to what is supported using the Open Virtual Terminal
   (QTVOPNVT) API [3].

   The standard VAR's supported to accomplish this are:

   VAR        VALUE              EXAMPLE           DESCRIPTION
   --------   ----------------   ----------------  -------------------
   USER       us-ascii char(x)   USERXYZ           User profile name

   x - up to a maximum of 10 characters

Murphy, Rieth & Stevens                                        [Page 11]

Internet Draft          5250 Telnet Enhancements           February 1998

   The custom USERVAR's defined to accomplish this are:

   USERVAR    VALUE              EXAMPLE           DESCRIPTION
   --------   ----------------   ----------------  -------------------
   IBMRSEED   binary(8)          8-byte hex field  Random client seed
   IBMSUBSPW  binary(10)         10-byte hex field Substitute password
   IBMCURLIB  us-ascii char(x)   QGPL              Current library
   IBMIMENU   us-ascii char(x)   MAIN              Initial menu
   IBMPROGRAM us-ascii char(x)   QCMD              Program to call

   x - up to a maximum of 10 characters

   In order to communicate the server random seed value to the client,
   the server will request a USERVAR name made up of a fixed part (the 8
   characters "IBMRSEED" immediately followed by an 8-byte hexadecimal
   variable part, which is the server random seed.  The client generates
   its own 8-byte random seed value, and uses both seeds to encrypt the
   password.  Both the encrypted password and the client random seed
   value are then sent to the server for authentication.  RFC 1572 rules
   will need to be adhered to when transmitting the client random seed
   and substituted password values to the server.  Specifically, since a
   typical environment string is a variable length hexadecimal field,
   the hexadecimal fields are required to be escaped and/or byte stuffed
   according to the RFC 854 [8], where any single byte could be mis-
   construed as a Telnet IAC or other Telnet option negotiation control
   character.  The client must escape and/or byte stuff any bytes which
   could be seen as a RFC 1572 [13] option, specifically VAR, VALUE, ESC
   and USERVAR.

   The following illustrates the encrypted case:

   AS/400 Telnet server             Enhanced Telnet client
   --------------------------       -------------------------------
   IAC DO NEW-ENVIRON          -->
                               <--  IAC WILL NEW-ENVIRON
   IAC SB NEW-ENVIRON SEND
   USERVAR "IBMRSEEDxxxxxxxx"
   USERVAR "IBMSUBSPW"
   VAR USERVAR IAC SE          -->
                                    IAC SB NEW-ENVIRON IS
                                    VAR "USER" VALUE "SMITH"
                                    USERVAR "IBMRSEED" VALUE "yyyyyyyy"
                                    USERVAR "IBMSUBSPW" VALUE "zzzzzzzz"
                               <--  IAC SE
                                .
                                .
   (other negotiations)         .

Murphy, Rieth & Stevens                                        [Page 12]

Internet Draft          5250 Telnet Enhancements           February 1998

   In this example, "xxxxxxxx" is an 8-byte hexadecimal random server
   seed, "yyyyyyyy" is an 8-byte hexadecimal random client seed and
   "zzzzzzzz" is an 8-byte hexadecimal encrypted password.  If the
   password is not valid, then the sign-on panel is displayed.  If the
   password is expired, then the Change Password panel is displayed.

   Actual bytes transmitted in the above example are shown in hex below.

   AS/400 Telnet server             Enhanced Telnet client
   --------------------------        -------------------------
   FF FD 27                    -->
                               <--  FF FB 27
   FF FA 27 01 03 49 42 4D
   52 53 45 45 44 78 78 78
   78 78 78 78 78 03 49 42
   4D 53 55 42 53 50 57 03
   00 FF F0                    -->
                                    FF FA 27 00 00 55 53 45
                                    52 01 53 4D 49 54 48 03
                                    49 42 4D 52 53 45 45 44
                                    01 79 79 79 79 79 79 79
                                    79 03 49 42 4D 53 55 42
                                    53 50 57 01 7A 7A 7A 7A
                               <--  7A 7A 7A 7A FF F0

   The following illustrates the clear-text case:

   AS/400 Telnet server             Enhanced Telnet client
   --------------------------        -------------------------
   IAC DO NEW-ENVIRON          -->
                               <--  IAC WILL NEW-ENVIRON
   IAC SB NEW-ENVIRON SEND
   USERVAR "IBMRSEEDxxxxxxxx"
   USERVAR "IBMSUBSPW"
   VAR USERVAR IAC SE          -->
                                    IAC SB NEW-ENVIRON IS
                                    VAR "USER" VALUE "SMITH"
                                    USERVAR "IBMRSEED" VALUE
                                    USERVAR "IBMSUBSPW" VALUE "yyyyyyyy"
                               <--  IAC SE
                                .
                                .
   (other negotiations)         .

   In this example, "xxxxxxxx" is an 8-byte hexadecimal random server
   seed, "yyyyyyyyyy" is a 10-byte us-ascii client clear-text password.
   If the password has expired, then the sign-on panel is displayed.

Murphy, Rieth & Stevens                                        [Page 13]

Internet Draft          5250 Telnet Enhancements           February 1998

   Actual bytes transmitted in the above example are shown in hex below.

   AS/400 Telnet server             Enhanced Telnet client
   --------------------------        -------------------------
   FF FD 27                    -->
                               <--  FF FB 27
   FF FA 27 01 03 49 42 4D
   52 53 45 45 44 78 78 78
   78 78 78 78 78 03 49 42
   4D 53 55 42 53 50 57 03
   00 FF F0                    -->
                                    FF FA 27 00 00 55 53 45
                                    52 03 53 4D 49 54 48 03
                                    49 42 4D 52 53 45 45 44
                                    01 03 49 42 4D 53 55 42
                                    53 50 57 01 7A 7A 7A 7A
                               <--  7A 7A 7A 7A FF F0

Murphy, Rieth & Stevens                                        [Page 14]

Internet Draft          5250 Telnet Enhancements           February 1998

7. Device Name Collision Processing

   Device name collision occurs when a Telnet client sends the Telnet
   server a virtual device name that it wants to use, but that device is
   already in use on the server.  When this occurs, the Telnet server
   sends a request to the client asking it to try another device name.
   The environment option negotiation uses the USERVAR name of DEVNAME
   to communicate the virtual device name.  The following shows how the
   Telnet server will request the Telnet client to send a different
   DEVNAME when device name collision occurs.

   AS/400 Telnet server             Enhanced Telnet client
   --------------------------        -------------------------
   IAC SB NEW-ENVIRON SEND
   VAR USERVAR IAC SE         -->

   Server requests all environment variables be sent.

                                    IAC SB NEW-ENVIRON IS USERVAR
                                    "DEVNAME" VALUE "MYDEVICE1"
                                    USERVAR "xxxxx" VALUE "xxx"
                                    ...
                              <--   IAC SE

   Client sends all environment variables, including DEVNAME.  Server
   tries to select device MYDEVICE1.  If the device is already in use,
   server requests DEVNAME be sent again.

   IAC SB NEW-ENVIRON SEND
   USERVAR "DEVNAME" IAC SE   -->

   Server sends a request for a single environment variable: DEVNAME

                                    IAC SB NEW-ENVIRON IS USERVAR
                              <--   "DEVNAME" VALUE "MYDEVICE2" IAC SE

   Client sends one environment variable, calculating a new value of
   MYDEVICE2.  If MYDEVICE2 is different from the last request, then
   server tries to select device MYDEVICE2, else server disconnects
   client.  If MYDEVICE2 is also in use, server will send DEVNAME request
   again, and keep doing so until it receives a device that is not in
   use, or the same device name twice in row.

Murphy, Rieth & Stevens                                        [Page 15]

Internet Draft          5250 Telnet Enhancements           February 1998

8. Enhanced Printer Emulation Support

   RFC 1572 style USERVAR variables have been defined to allow a
   compliant Telnet client more control over the Telnet server virtual
   device on the AS/400.  These USERVAR's allow the client Telnet to
   select a previously created virtual device or auto-create a new
   virtual device with requested attributes.

   This makes the enhancements available to any Telnet client that
   chooses to support the new negotiations.

   The USERVAR's defined to accomplish this are:

   USERVAR       VALUE            EXAMPLE           DESCRIPTION
   ------------- ---------------- ----------------  -------------------
   DEVNAME       us-ascii char(x) PRINTER1          Printer device name
   IBMIGCFEAT    us-ascii char(6) 2424J0            IGC feature (DBCS)
   IBMMSGQNAME   us-ascii char(x) QSYSOPR           *MSGQ name
   IBMMSGQLIB    us-ascii char(x) QSYS              *MSGQ library
   IBMFONT       us-ascii char(x) 12                Font
   IBMFORMFEED   us-ascii char(1) C | U | A         Formfeed
   IBMBUFFERSIZE us-ascii char(y) 4096              Reserved
   IBMTRANSFORM  us-ascii char(1) 1 | 0             Transform
   IBMMFRTYPMDL  us-ascii char(x) *IBM42023         Mfg. type and model
   IBMPPRSRC1    binary(1)        1-byte hex field  Paper source 1
   IBMPPRSRC2    binary(1)        1-byte hex field  Paper source 2
   IBMENVELOPE   binary(1)        1-byte hex field  Envelope
   IBMASCII899   us-ascii char(1) 1 | 0             ASCII 899 support
   IBMWSCSTNAME  us-ascii char(x) *NONE             WCS name
   IBMWSCSTLIB   us-ascii char(x) *LIBL             WCS library
   IBMIGCFEAT    us-ascii char(6) 2424J0            IGC feature (DBCS)

   x - up to a maximum of 10 characters
   y - up to a maximum of 5 characters

   The "IBM" prefix on the USERVAR's denotes AS/400 specific attributes.

   For a description of most of these parameters (drop the "IBM" from
   the USERVAR) and their permissible values, refer to Chapter 8 in the
   Communications Configuration Reference [5].

Murphy, Rieth & Stevens                                        [Page 16]

Internet Draft          5250 Telnet Enhancements           February 1998

   The IBMPPRSRC1, IBMPPRSRC2 and IBMENVELOPE custom USERVAR's do not
   map directly to their descriptions in Chapter 8 in the Communications
   Configuration Reference [5].  To map these, use the index listed
   here:

   IBMPPRSRC1    HEX     IBMPPRSRC2    HEX     IBMENVELOPE    HEX
   ----------   -----    ----------   -----    -----------   -----
   *NONE        'FF'X    *NONE        'FF'X    *NONE         'FF'X
   *MFRTYPMDL   'FE'X    *MFRTYPMDL   'FE'X    *MFRTYPMDL    'FE'X
   *SAME        '00'X    *SAME        '00'X    *SAME         '00'X
   *LETTER      '01'X    *LETTER      '01'X    *B5           '06'X
   *LEGAL       '02'X    *LEGAL       '02'X    *MONARCH      '09'X
   *EXECUTIVE   '03'X    *EXECUTIVE   '03'X    *NUMBER9      '0A'X
   *A4          '04'X    *A4          '04'X    *NUMBER10     '0B'X
   *A5          '05'X    *A5          '05'X    *C5           '0C'X
   *B5          '06'X    *B5          '06'X    *DL           '0D'X
   *CONT80      '07'X    *CONT80      '07'X
   *CONT132     '08'X    *CONT132     '08'X
   *A3          '0E'X    *A3          '0E'X
   *B4          '0F'X    *B4          '0F'X
   *LEDGER      '10'X    *LEDGER      '10'X

   Note 1:  For IBMPPRSRC2, *CONT80 and *CONT132 support starts at V3R7.

   Note 2:  For IBMPPRSRC1 and IBMPPRSRC2, *A3, *B4 and *LEDGER support
   starts at V3R7.

Murphy, Rieth & Stevens                                        [Page 17]

Internet Draft          5250 Telnet Enhancements           February 1998

9. Telnet Printer Terminal Types

   New Telnet options are defined for the printer pass-through mode of
   operation.  To enable printer pass-through mode, both the client and
   server must agree to at least support the Transmit-Binary, End-Of-
   Record, and Terminal-Type Telnet options.  The following are new
   terminal types for printers:

   TERMINAL-TYPE  DESCRIPTION
   -------------  -------------------
   IBM-5553-B01   Double-Byte printer
   IBM-3812-1     Single-Byte printer

   Specific characteristics of the IBM-5553-B01 or IBM-3812-1 printers
   are specified through the USERVAR IBMMFRTYPMDL, which specifies the
   manufacturer type and model.

   An example of a typical negotiation process to establish printer
   pass-through mode of operation is shown below.  In this example, the
   server initiates the negotiation by sending the DO TERMINAL-TYPE
   request.

Murphy, Rieth & Stevens                                        [Page 18]

Internet Draft          5250 Telnet Enhancements           February 1998

   AS/400 Telnet server             Enhanced Telnet client
   --------------------------       --------------------------
   IAC DO NEW-ENVIRON         -->
                              <--   IAC WILL NEW-ENVIRON
   IAC SB NEW-ENVIRON SEND
   VAR USERVAR IAC SE         -->
                                    IAC SB NEW-ENVIRON IS
                                    USERVAR "DEVNAME" VALUE "PCPRINTER"
                                    USERVAR "IBMMSGQNAME" VALUE "QSYSOPR"
                                    USERVAR "IBMMSGQLIB" VALUE "*LIBL"
                                    USERVAR "IBMTRANSFORM" VALUE "0"
                                    USERVAR "IBMFONT" VALUE "12"
                                    USERVAR "IBMFORMFEED" VALUE "C"
                                    USERVAR "IBMBUFFERSIZE" VALUE "1024"
                                    USERVAR "IBMPPRSRC1" VALUE ESC '01'X
                                    USERVAR "IBMPPRSRC2" VALUE '04'X
                                    USERVAR "IBMENVELOPE" VALUE IAC 'FF'X
                              <--   IAC SE
   IAC DO TERMINAL-TYPE       -->
                              <--   IAC WILL TERMINAL-TYPE
   IAC SB TERMINAL-TYPE SEND
   IAC SE                     -->
                                    IAC SB TERMINAL-TYPE IS IBM-3812-1
                              <--   IAC SE
   IAC DO BINARY              -->
                              <--   IAC WILL BINARY
   IAC DO EOR                 -->
                              <--   IAC WILL EOR

   Some points about the above example.  The IBMPPRSRC1 value requires
   escaping the value using ESC according to RFC 1572 [13].  The
   IBMPPRSRC2 does not require an ESC character since '04'X has no
   conflict with RFC 1572 options.  Finally, to send 'FF'X for the
   IBMENVELOPE value, escape the 'FF'X value by using another 'FF'X
   (called "doubling"), so as not to have the value interpreted as a
   Telnet character per RFC 854 [8].

   Actual bytes transmitted in the above example are shown in hex below.

Murphy, Rieth & Stevens                                        [Page 19]

Internet Draft          5250 Telnet Enhancements           February 1998

   AS/400 Telnet server             Enhanced Telnet client
   --------------------------       --------------------------
   FF FD 27                    -->
                               <--  FF FB 27
   FF FA 27 01 00 03 FF F0     -->
                                    FF FA 27 00 03 44 45 56
                                    4E 41 4D 45 01 50 43 50
                                    52 49 4E 54 45 52 03 49
                                    42 4D 4D 53 47 51 4E 41
                                    4D 45 01 51 53 59 53 4F
                                    50 52 03 49 42 4D 4D 53
                                    47 51 4C 49 42 01 2A 4C
                                    49 42 4C 03 49 42 4D 54
                                    52 41 4E 53 46 4F 52 4D
                                    01 30 03 49 42 4D 46 4F
                                    4E 54 01 31 32 03 49 42
                                    4D 46 4F 52 4D 46 45 45
                                    44 01 43 03 49 42 4D 42
                                    55 46 46 45 52 53 49 5A
                                    45 01 31 30 32 34 03 49
                                    42 4D 50 50 52 53 52 43
                                    31 01 02 01 03 49 42 4D
                                    50 50 52 53 52 43 32 01
                                    04 03 49 42 4D 45 4E 56
                                    45 4C 4F 50 45 01 FF FF
                               <--  FF F0
   FF FD 18                    -->
                               <--  FF FB 18
   FF FA 18 01 FF F0           -->
                                    FF FA 18 00 49 42 4D 2D
                               <--  33 38 31 32 2D 31 FF F0
   FF FD 00                    -->
                               <--  FF FB 00
   FF FD 19                    -->
                                    FF FB 19

Murphy, Rieth & Stevens                                        [Page 20]

Internet Draft          5250 Telnet Enhancements           February 1998

10. Telnet Printer Startup Response Record for Printer Emulators

   Once Telnet negotiation for a 5250 pass-through mode is completed,
   the 5250 Telnet server will initiate a virtual printer power-on
   sequence on behalf of the Telnet client.  The Telnet server will
   supply a Startup Response Record to the Telnet client with the status
   of the printer power-on sequence, indicating success or failure of
   the virtual printer power-on sequence.

   This section shows an example of two Startup Response Records.  The
   source device is a type 3812 model 01 printer with name "PCPRINTER"
   on the target system "TARGET".

   Figure 1 shows an example of a successful response; Figure 2 shows an
   example of an error response.

Murphy, Rieth & Stevens                                        [Page 21]

Internet Draft          5250 Telnet Enhancements           February 1998

10.1 Example of a Success Response Record

   The response record in Figure 1 was sent by an AS/400 at Release
   V4R2.  It is an example of the target sending back a successful
   Startup Response Record.

   +--------------------------------------------------------------------+
   |       +-----  Pass-Through header                                  |
   |       |          +---  Response data                               |
   |       |          |            +----  Start diagnostic information  |
   |       |          |            |                                    |
   | +----------++----------++---------------------------------------   |
   | |          ||          ||                                          |
   | 004912A090000560060020C0003D0000C9F9F0F2E3C1D9C7C5E34040D7C3D7D9   |
   |                                 |      | T A R G E T     P C P R   |
   |                                 +------+                           |
   |                           Response Code (I902)                     |
   |                                                                    |
   | ----------------------------------------------------------------   |
   |                                                                    |
   | C9D5E3C5D9400000000000000000000000000000000000000000000000000000   |
   |  I N T E R                                                         |
   |                                                                    |
   |                  +------- End of diagnostic information            |
   |                  |                                                 |
   | -----------------+                                                 |
   |                  |                                                 |
   | 000000000000000000                                                 |
   +--------------------------------------------------------------------+
    Figure 1. Example of a success response record.

   - '0049'X = Length pass-through data, including this length field
   - '12A0'X = GDS LU6.2 header
   - '90000560060020C0003D0000'X = Fixed value fields
   - 'C9F9F0F2'X                 = Response Code (I902)
   - 'E3C1D9C7C5E34040'X         = System Name (TARGET)
   - 'D7C3D7D9C9D5E3C5D940'X     = Object Name (PCPRINTER)

Murphy, Rieth & Stevens                                        [Page 22]

Internet Draft          5250 Telnet Enhancements           February 1998

10.2 Example of an Error Response Record

   The response record in Figure 2 is one that reports an error.  The
   virtual device named "PCPRINTER", is not available on the target
   system "TARGET", because the device is not available.  You would
   normally see this error if the printer was already assigned to
   another Telnet session.

   +--------------------------------------------------------------------+
   |       +-----  Pass-Through header                                  |
   |       |          +---  Response data                               |
   |       |          |            +----  Start diagnostic information  |
   |       |          |            |                                    |
   | +----------++----------++---------------------------------------   |
   | |          ||          ||                                          |
   | 004912A09000056006008200003D0000F8F9F0F2E3C1D9C7C5E34040D7C3D7D9   |
   |                                 |      | T A R G E T     P C P R   |
   |                                 +------+                           |
   |                           Response Code (8902)                     |
   |                                                                    |
   | ----------------------------------------------------------------   |
   |                                                                    |
   | C9D5E3C5D9400000000000000000000000000000000000000000000000000000   |
   |  I N T E R                                                         |
   |                                                                    |
   |                  +------- End of diagnostic information            |
   |                  |                                                 |
   | -----------------+                                                 |
   |                  |                                                 |
   | 000000000000000000                                                 |
   +--------------------------------------------------------------------+
    Figure 2. Example of an error response record.

   - '0049'X = Length pass-through data, including this length field
   - '12A0'X = GDS LU6.2 header
   - '90000560060020C0003D0000'X = Fixed value fields
   - 'F8F9F0F2'X                 = Response Code (8902)
   - 'E3C1D9C7C5E34040'X         = System Name (TARGET)
   - 'D7C3D7D9C9D5E3C5D940'X     = Object Name (PCPRINTER)

Murphy, Rieth & Stevens                                        [Page 23]

Internet Draft          5250 Telnet Enhancements           February 1998

10.3 Response Codes

   The Start-Up Response Record success response codes:

   CODE    DESCRIPTION
   ----    ------------------------------------------------------
   I901    Virtual device has less function than source device
   I902    Session successfully started
   I906    Automatic sign-on requested, but not allowed.
           Session still allowed; a sign-on screen will be
           coming.

   The Start-Up Response Record error response codes:

   CODE    DESCRIPTION
   ----    ------------------------------------------------------
   2702    Device description not found.
   2703    Controller description not found.
   2777    Damaged device description.
   8901    Device not varied on.
   8902    Device not available.
   8903    Device not valid for session.
   8906    Session initiation failed.
   8907    Session failure.
   8910    Controller not valid for session.
   8916    No matching device found.
   8917    Not authorized to object.
   8918    Job canceled.
   8920    Object partially damaged.
   8921    Communications error.
   8922    Negative response received.
   8923    Start-up record built incorrectly.
   8925    Creation of device failed.
   8928    Change of device failed.
   8929    Vary on or vary off failed.
   8930    Message queue does not exist.
   8934    Start-up for S/36 WSF received.
   8935    Session rejected.
   8936    Security failure on session attempt.
   8937    Automatic sign-on rejected.
   8940    Automatic configuration failed or not allowed.
   I904    Source system at incompatible release.

Murphy, Rieth & Stevens                                        [Page 24]

Internet Draft          5250 Telnet Enhancements           February 1998

11. Printer Steady-State Pass-Through Interface

   The information in this section applies to the passthrough session
   after the receipt of startup confirmation records is complete.

   Following is the printer header interface used by Telnet.

   +--------------------------------------------------------------------+
   |   +-- Length of structure (LLLL)                                   |
   |   |                                                                |
   |   |    +-- GDS identifier                                          |
   |   |    |                                                           |
   |   |    |    +-- Data flow record                                   |
   |   |    |    |                                                      |
   |   |    |    |   +-- Length of pass-through specific header (LL)    |
   |   |    |    |   |                                                  |
   |   |    |    |   |   +-- Flags                                      |
   |   |    |    |   |   |                                              |
   |   |    |    |   |   |   +-- Printer operation code                 |
   |   |    |    |   |   |   |                                          |
   |   |    |    |   |   |   |      +-- Diagnostic field - zero pad to  |
   |   |    |    |   |   |   |      |   LL specified                    |
   |   |    |    |   |   |   |      |                                   |
   |   |    |    |   |   |   |      |            +-- Printer data       |
   |   |    |    |   |   |   |      |            |                      |
   | +--+ +--+ +--+ ++ +--+ ++ +----------+ +----------------+          |
   | |  | |  | |  | || |  | || |          | |                |          |
   | xxxx 12A0 xxxx xx xxxx xx xxxxxxxxxxxx ... print data ...          |
   |                                                                    |
   +--------------------------------------------------------------------+
    Figure 3. Layout of the printer pass-through header

   BYTES 0-1:   Length of structure including this field (LLLL)

   BYTES 2-3:   GDS Identifier ('12A0'X)

Murphy, Rieth & Stevens                                        [Page 25]

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   BYTE 4-5:    Data flow record

                This field contains flags that describe what type of data
                pass-through should expect to find following this header.
                Generally, bits 0-2 in the first byte are mutually exclusive
                (that is, if one of them is set to '1'B, the rest will
                be set to '0'B.) The bits, and their meanings follow.

                BIT       DESCRIPTION

                0         Start-Up confirmation
                1         Termination record
                2         Start-Up Record
                3         Diagnostic information included
                4 - 5     Reserved
                6         Reserved
                7         Printer record
                8 - 13    Reserved
                14        Client-originated (inbound) printer record
                15        Server-originated (outbound) printer record

   BYTE 6:      Length printer pass-through header including this field (LL)

   BYTES 7-8:   Flags

     BYTE 7 BITS:  xxxx x111 --> Reserved
                   xxxx 1xxx --> Last of chain
                   xxx1 xxxx --> First of chain
                   xx1x xxxx --> Printer now ready
                   x1xx xxxx --> Intervention Required
                   1xxx xxxx --> Error Indicator

     BYTE 8 BITS:  xxxx xxxx --> Reserved

   BYTE 9:      Printer operation code

                '01'X  Print/Print complete
                '02'X  Clear Print Buffers

Murphy, Rieth & Stevens                                        [Page 26]

Internet Draft          5250 Telnet Enhancements           February 1998

   BYTE 10-LL:  Diagnostic information (1)

     If BYTE 7 = x1xx xxxx then bytes 10-LL may contain: (2)
        Printer not ready            C9 00 03 02 51 00
        End of forms                 C9 00 03 02 50 00
        Graphic check                C9 00 03 02 26 00
        Data stream exception        C9 00 03 02 66 00
        Data stream exception        C9 00 03 02 67 00
        Data stream exception        C9 00 03 02 68 00
        Data stream exception        C9 00 03 02 69 00

     If BYTE 7 = 1xxx xxxx then bytes 10-LL may contain: (3)
        Cancel                       08 11 02 00 00 00
        Invalid print parameter      08 11 02 29 00 00
        Invalid print command        08 11 02 28 00 00

   Figure notes:

   1.  LL is the length of the structure defined in Byte 6.  If
       no additional data is present, the remainder of the
       structure must be padded with zeroes.

   2.  These are printer signal commands.  Further information on
       these commands may be obtained from the 5494 Remote
       Control Unit Functions Reference guide [2].  Refer to your
       printer documentation for more specific information on
       these data stream exceptions.

   3.  These are printer negative responses.  Further information
       on these commands may be obtained from the 5494 Remote
       Control Unit Functions Reference guide [2].

   The print data will start in byte LL+1.

Murphy, Rieth & Stevens                                        [Page 27]

Internet Draft          5250 Telnet Enhancements           February 1998

11.1 Example of a Print Record

   Figure 4 shows the server sending the client data with a print
   record.  This is normally seen following receipt of a Success
   Response Record, such as the example in Figure 1.

   +--------------------------------------------------------------------+
   |   +-- Length of structure (LLLL)                                   |
   |   |    +-- GDS identifier                                          |
   |   |    |    +-- Data flow record                                   |
   |   |    |    |   +-- Length of pass-through specific header (LL)    |
   |   |    |    |   |   +-- Flags                                      |
   |   |    |    |   |   |   +-- Printer operation code                 |
   |   |    |    |   |   |   |      +-- Zero pad to LL specified (0A)   |
   |   |    |    |   |   |   |      |            +-- Printer data       |
   |   |    |    |   |   |   |      |            |                      |
   | +--+ +--+ +--+ ++ +--+ ++ +----------+ +---------------------------|
   | |  | |  | |  | || |  | || |          | |                           |
   | 0085 12A0 0101 0A 1800 01 000000000000 34C4012BD20345FF2BD2044C0002|
   |                                                                    |
   | ------------------------------------------------------------       |
   |                                                                    |
   | 2BD2040D00002BD20A8501010201030204022BD20309022BD2061100014A       |
   |                                                                    |
   | ------------------------------------------------------------       |
   |                                                                    |
   | 402BD20601010000012BD306F60000FFFF2BD20A48000001000000010100       |
   |                                                                    |
   | ------------------------------------------------------------       |
   |                                                                    |
   | 2BD10705000B0090012BD2044900F02BD206404A403DE02BD2041500F034       |
   |                                                                    |
   |    end of printer data                                             |
   | -------------------------+                                         |
   |                          |                                         |
   | C4012BD10381FF002BC8034001                                         |
   +--------------------------------------------------------------------+
    Figure 4. Server sending client data with a print record

   - '0085'X         = Logical record length, including this byte (LLLL)
   - '12A0'X         = GDS LU6.2 header
   - '0101'X         = Data flow record (server to client)
   - '0A'X           = Length of pass-through specific header (LL)
   - '1800'X         = First of chain / Last of chain indicators
   - '01'X           = Print
   - '000000000000'X = Zero pad header to LL specified
   - '34C401'X       = First piece of data for spooled data
   - Remainder is printer data/commands/orders

Murphy, Rieth & Stevens                                        [Page 28]

Internet Draft          5250 Telnet Enhancements           February 1998

11.2 Example of a Print Complete Record

   Figure 5 shows the client sending the server a print complete record.
   This would normally follow receipt of a print record, such as the
   example in Figure 4.  This indicates successful completion of a print
   request.

   +--------------------------------------------------------------------+
   |   +-- Length of structure (LLLL)                                   |
   |   |    +-- GDS identifier                                          |
   |   |    |    +-- Data flow record                                   |
   |   |    |    |   +-- Length of pass-through specific header (LL)    |
   |   |    |    |   |   +-- Flags                                      |
   |   |    |    |   |   |   +-- Printer operation code                 |
   |   |    |    |   |   |   |                                          |
   | +--+ +--+ +--+ ++ +--+ ++                                          |
   | |  | |  | |  | || |  | ||                                          |
   | 000A 12A0 0102 04 0000 01                                          |
   +--------------------------------------------------------------------+
    Figure 5. Client sending server a print complete record

   - '000A'X = Logical record length, including this byte (LLLL)
   - '12A0'X = GDS LU6.2 header
   - '0102'X = Data flow response record (client to server)
   - '04'X   = Length of pass-through specific header (LL)
   - '0000'X = Good Response
   - '01'X   = Print Complete

Murphy, Rieth & Stevens                                        [Page 29]

Internet Draft          5250 Telnet Enhancements           February 1998

11.3 Example of a Null Print Record

   Figure 6 shows the server sending the client a null print record.
   The null print record is the last print command the server sends to
   the client for a print job, and indicates to the printer there is no
   more data.

   This example would normally follow any number of print records, such
   as the example in Figure 4.  This indicates successful completion of
   a print job.  The client normally responds to this null print record
   with another print complete record, such as in Figure 5.

   +--------------------------------------------------------------------+
   |   +-- Length of structure (LLLL)                                   |
   |   |    +-- GDS identifier                                          |
   |   |    |    +-- Data flow record                                   |
   |   |    |    |   +-- Length of pass-through specific header (LL)    |
   |   |    |    |   |   +-- Flags                                      |
   |   |    |    |   |   |   +-- Printer operation code                 |
   |   |    |    |   |   |   |      +-- Zero pad to LL specified (0A)   |
   |   |    |    |   |   |   |      |        +-- Printer data           |
   |   |    |    |   |   |   |      |        |                          |
   | +--+ +--+ +--+ ++ +--+ ++ +----------+ ++                          |
   | |  | |  | |  | || |  | || |          | ||                          |
   | 0011 12A0 0101 0A 0800 01 000000000000 00                          |
   +--------------------------------------------------------------------+
    Figure 6. Server sending client a null print record

   - '0011'X         = Logical record length, including this byte
   - '12A0'X         = GDS LU6.2 header
   - '0101'X         = Data flow record
   - '0A'X           = Length of pass-through specific header (LL)
   - '0800'X         = Last of Chain
   - '01'X           = Print
   - '000000000000'X = Zero pad header to LL specified
   - '00'X           = Null data byte

Murphy, Rieth & Stevens                                        [Page 30]

Internet Draft          5250 Telnet Enhancements           February 1998

12. End-to-End Print Example

   The next example shows a full print exchange between a Telnet client
   and server for a 526 byte spooled file.  Selective translation of the
   hexadecimal streams into 1) Telnet negotiations and 2) ASCII/EBCDIC
   characters are done to aid readability.  Telnet negotiations are
   delimited by '(' and ')' parenthesis characters; ASCII/EBCDIC
   conversions are bracketed by '|' vertical bar characters.

   AS/400 Telnet server                  Enhanced Telnet client
   ---------------------------------     ---------------------------------
   FFFD27                            -->

   (IAC DO NEW-ENVIRON)
                                     <-- FFFB27

                                         (IAC WILL NEW-ENVIRON)

   FFFD18FFFA270103 49424D5253454544
   7CF9630A63D18004 0003FFF0         -->

   (IAC DO TERMINAL-TYPE
   IAC SB NEW-ENVIRON SEND USERVAR
   IBMRSEED xxxxxxxx VAR USERVAR
   IAC SE)

                                         FFFB18FFFA270003 49424D5253454544
                                         7CF9630A63D18004 00034445564E414D
                                         450144554D4D5950 52540349424D4D53
                                         47514E414D450151 5359534F50520349
                                         424D4D5347514C49 42012A4C49424C03
                                         49424D464F4E5401 3031310349424D46
                                         4F524D4645454401 0349424D42554646
                                         455253495A450137 36380349424D5452
                                     <-- 414E53464F524D01 30FFF0

                                         (IAC WILL TERMINAL-TYPE IAC SB
                                          NEW-ENVIRON IS USERVAR
                                          IBMRSEED xxxxxxxx VAR
                                          USERVAR DEVNAME VALUE DUMMYPRT
                                          USERVAR IBMMSGQNAME VALUE
                                          USERVAR IBMMSGQLIB VALUE *LIBL
                                          USERVAR IBMFONT VALUE 011
                                          USERVAR IBMFORMFEED VALUE
                                          USERVAR IBMBUFFERSIZE VALUE 768
                                          USERVAR IBMTRANSFORM VALUE 0
                                          IAC SE)

Murphy, Rieth & Stevens                                        [Page 31]

Internet Draft          5250 Telnet Enhancements           February 1998

   FFFA1801FFF0                      -->

   (IAC DO SB TERMINAL-TYPE SEND
   IAC SE)
                                     <-- FFFA180049424D2D 333831322D31FFF0

                                         (IAC SB TERMINAL-TYPE IS
                                          IBM-3812-1 IAC SE)

   FFFD19                            -->

   (IAC DO EOR)
                                     <-- FFFB19

                                         (IAC WILL EOR)

   FFFB19FFFD00FFFB 00               -->

   (IAC WILL EOR IAC DO BINARY
   IAC WILL BINARY)
                                     <-- FFFD19FFFB00FFFD 00

                                         (IAC DO EOR IAC WILL BINARY
                                          IAC DO BINARY)

   FFFD00                            -->

   (IAC DO BINARY)

   FFFB00004912A090 000560060020C000     |..........-...{.|
   3D0000C9F9F0F2C1 E2F4F0F040404044     |...I902AS400   D| (EBCDIC)
   554D4D5950525440 4000000000000000     |UMMYPRT         |
   0000000000000000 0000000000000000     |................|
   0000000000000000 00000000FFEF     --> |..............  |

   (IAC WILL BINARY ... 73-byte
    startup success response
    record ... IAC EOR)

Murphy, Rieth & Stevens                                        [Page 32]

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   007812A001010A18 0001000000000000     |.x..............|
   036611180D12141B 461B481B4F1B541B     |.f......F.H.O.T.| (ASCII)
   55001B57001B3500 1B5F001B2D001B36     |U..W..5.._..-..6|
   1B49021B461B481B 2D001B410C1B321B     |.I..F.H.-..A..2.|
   57001B461B49121B 57001B461B49121B     |W..F.I..W..F.I..|
   461B481B2D001B41 0C1B321B57001B46     |F.H.-..A..2.W..F|
   1B49121B57001B46 1B49121B57001B46     |.I..W..F.I..W..F|
   1B49121B410C1B32 FFEF             --> |.I..A..2..      |

   (... 120-byte print record ...
    ... first of chain ...
    ... last of chain ... IAC EOR)

                                     <-- 000A12A001020400 0001FFEF

                                         (10-byte print complete header)

   008B12A001010A18 0001000000000000     |................|
   03241B57001B461B 49121B410C1B321B     |.$.W..F.I..A..2.| (ASCII)
   43421B410C1B321B 410C1B320A0A0A0A     |CB.A..2.A..2....|
   0A1B410C1B320350 2020202020202020     |..A..2.P        |
   2020202020202020 2020202020202050     |               P|
   72696E74204B6579 204F757470757420     |rint Key Output |
   2020202020202020 2020202020202020     |                |
   2020202020202020 2020202020202050     |               P|
   616765202020310D 03010DFFEF       --> |age   1......   |

   (... 139-byte print record ...
    ... first of chain ...
    ... last of chain ... IAC EOR)

                                     <-- 000A12A001020400 0001FFEF

                                         (10-byte print complete header)

   031012A001010A10 0001000000000000     |................|
   03010C03241B5700 1B461B49121B410C     |....$.W..F.I..A.| (ASCII)
   1B321B43421B410C 1B321B410C1B320A     |.2.CB.A..2.A..2.|
   0A0A0A0A1B410C1B 3203502020202020     |.....A..2.P     |
   2020202020202020 2020202020202020     |                |
   20205072696E7420 4B6579204F757470     |  Print Key Outp|
   7574202020202020 2020202020202020     |ut              |
   2020202020202020 2020202020202020     |                |
   2020506167652020 20310D03010D03FF     |  Page   1......|
   FF0A202020203537 3639535331205634     |..    5769SS1 V4|
   52324D3020393830 3232382020202020     |R2M0 980228     |
   2020202020202020 2020204153343030     |           AS400|
   2020202020202020 2020202020202030     |               0|

Murphy, Rieth & Stevens                                        [Page 33]

Internet Draft          5250 Telnet Enhancements           February 1998

   342F32392F393820 2031363A30393A30     |4/29/98  16:09:0|
   340D0A0D0A202020 20446973706C6179     |4....    Display|
   2044657669636520 202E202E202E202E     | Device  . . . .|
   202E203A20205150 4144455630303130     | . :  QPADEV0010|
   0D0A202020205573 657220202E202E20     |..    User  . . |
   2E202E202E202E20 2E202E202E202E20     |. . . . . . . . |
   3A202044554D4D59 5553520D0A0D0A20     |:  DUMMYUSR.... |
   2020202020202020 2020202020202020     |                |
   2020202020202020 2020202020202020     |                |
   436F6D6D616E6420 456E747279202020     |Command Entry   |
   2020202020202020 2020202020202020     |                |
   2020202020204153 3430300D0A202020     |      AS400..   |
   03FFFF2020202020 2020202020202020     |...             |
   2020202020202020 2020202020202020     |                |
   2020202020202020 2020202020202020     |                |
   310D0A2050726576 696F757320636F6D     |1.. Previous com|
   6D616E647320616E 64206D6573736167     |mands and messag|
   65733A0D0A0D0A20 2020284E6F207072     |es:....   (No pr|
   6576696F75732063 6F6D6D616E647320     |evious commands |
   6F72206D65737361 676573290D0A0D0A     |or messages)....|
   0D0A0D0A0D0A0D0A 0D0A0D0A0D0A0D0A     |................|
   0D0A202020202020 2020202020202020     |..              |
   2020202020202020 2020202020202020     |                |
   2020202020202020 2020202020202020     |                |
   2020202020202020 2020202020202020     |                |
   2020202020202020 202020426F74746F     |           Botto|
   6D0D0A20547903D6 706520636F6D6D61     |m.. Ty..pe comma|
   6E642C2070726573 7320456E7465722E     |nd, press Enter.|
   0D0A203D3D3D3E20 53616D706C652050     |.. ===> Sample P|
   72696E7420536372 65656E2E2E2E0D0A     |rint Screen.....|
   0D0A0D0A0D0A2046 333D457869742020     |...... F3=Exit  |
   2046343D50726F6D 707420202046393D     | F4=Prompt   F9=|
   5265747269657665 2020204631303D49     |Retrieve   F10=I|
   6E636C7564652064 657461696C656420     |nclude detailed |
   6D6573736167FFEF                  --> |messag..        |

   (... 784-byte print record ...
    ... first of chain ... IAC EOR)

                                     <-- 000A12A001020400 0001FFEF

                                         (10-byte print complete header)

Murphy, Rieth & Stevens                                        [Page 34]

Internet Draft          5250 Telnet Enhancements           February 1998

   006812A001010A00 0001000000000000     |.h..............|
   65730D0A20463131 3D446973706C6179     |es.. F11=Display| (ASCII)
   2066756C6C202020 2020204631323D43     | full      F12=C|
   616E63656C202020 204631333D496E66     |ancel    F13=Inf|
   6F726D6174696F6E 2041737369737461     |ormation Assista|
   6E74202020463234 3D4D6F7265206B65     |nt   F24=More ke|
   79730D0A0D0A0D0C FFEF             --> |ys........      |

   (... 104-byte print record ...
    IAC EOR)

                                     <-- 000A12A001020400 0001FFEF

                                         (10-byte print complete header)

   002912A001010A00 0001000000000000     |.)..............|
   03171B461B481B4F 1B541B55001B5700     |...F.H.O.T.U..W.| (ASCII)
   1B35001B5F001B2D 00FFEF           --> |.5.._..-...     |

   (... 41-byte print record ...
    IAC EOR)

                                     <-- 000A12A001020400 0001FFEF

                                         (10-byte print complete header)

   001112A001010A08 0001000000000000
   00FFEF                            -->

   (... 17-byte NULL print record ...
    ... last of chain ... IAC EOR)

                                     <-- 000A12A001020400 0001FFEF

                                         (10-byte print complete header)

Murphy, Rieth & Stevens                                        [Page 35]

Internet Draft          5250 Telnet Enhancements           February 1998

13. Author's Note

   Discussion of this draft should occur in one of these mailing lists:

      TN3270E List (Roger Fajman [email-masked]).  Send subscription
      requests as e-mail with "subscribe tn3270e your_full_name" to
      [email-masked].

      Midrange-L List (David Gibbs [email-masked]).  Send
      subscription requests as email with "subscribe midrange-l
      your_internet_address" to [email-masked].

      Telnet Working Group Mailing List:  Send subscription requests as
      email with "subscribe telnet-ietf" to telnet-ietf-
      [email-masked].

14. References

   [1]  IBM, "IBM 5250 Information Display System, Functions Reference
   Manual", SA21-9247-6, March 1987.

   [2]  IBM, "5494 Remote Control Unit, Functions Reference", SC30-
   3533-03, November 1994.

   [3]  IBM, "AS/400 System API Reference", SC41-5801, February 1998.

   [4]  IBM, "AS/400 TCP/IP Configuration and Reference", SC41-5420-01,
   February 1998.

   [5]  IBM, "AS/400 Communications Configuration", SC41-5401-00, August
   1997.

   [6] IBM, "SNA Formats", GA27-3136-13, November 1993.

   [7] IBM, "Using the Pageprinter 3812 with System/36 or System/38",
   S544-3343-01, September 1997.

   [8]  Postel, J. and J. Reynolds, "TELNET PROTOCOL SPECIFICATION", RFC
   854, USC/Information Sciences Institute, May 1983.

   [9]  Postel, J. and J. Reynolds, "TELNET OPTION SPECIFICATIONS", RFC
   855, USC/Information Sciences Institute, May 1983.

   [10]  Postel, J. and J. Reynolds, "TELNET BINARY TRANSMISSION", RFC
   856, USC/Information Sciences Institute, May 1983.

   [11]  VanBokkeln, J., "Telnet Terminal-Type Option", RFC 1091, FTP

Murphy, Rieth & Stevens                                        [Page 36]

Internet Draft          5250 Telnet Enhancements           February 1998

   Software, Inc., February 1989.

   [12]  Postel, J. and J. Reynolds, "TELNET END OF RECORD OPTION", RFC
   885, USC/Information Sciences Institute, December 1983.

   [13]  Alexander, S., "Telnet Environment Option", RFC 1572, Lachman
   Technology, Inc., January 1994.

   [14]  Chmielewski, P., "5250 Telnet Interface", RFC 1205, IBM
   Corporation, February 1991.

   [15]  Postel, J. and J. Reynolds, "TELNET SUPPRESS GO AHEAD OPTION",
   RFC 858, Information Sciences Institute, May 1983.

   [16]  IBM, "AS/400 National Language Support", SC41-5101-01, February
   1998.

   [17]  Data Encryption Standard, Federal Information Processing
   Standards Publication 46, January 15, 1977.

   [18] Reynolds, J., and J. Postel, "Assigned Numbers", RFC 1700, STD
   2, USC/Information Sciences Institute, October 1994.

15. Security Considerations

   Security considerations of passwords are discussed in Section 6.

16. Author's Address

   Thomas E. Murphy, Jr.                 Phone:  (607) 752-5482
   IBM Corporation                       Fax:    (607) 752-5421
   1701 North Street                     Email:  [email-masked]
   Endicott, NY 13760

   Paul F. Rieth                         Phone:  (607) 752-5474
   IBM Corporation                       Fax:    (607) 752-5421
   1701 North Street                     Email:  [email-masked]
   Endicott, NY 13760

   Jeffrey S. Stevens                    Phone:  (607) 752-5488
   IBM Corporation                       Fax:    (607) 752-5421
   1701 North Street                     Email:  [email-masked]
   Endicott, NY 13760

Murphy, Rieth & Stevens                                        [Page 37]

Internet Draft          5250 Telnet Enhancements           February 1998

17. Relation to Other RFC's

   UPDATES

      This draft is an update to RFC 1205 [14], which describes the 5250
      Telnet Interface.  This update enhances that description to
      include device negotiation as well as printer support.

      This draft makes use of RFC 1572 [13] to enhance communications
      with 5250 Telnet clients.  RFC 1572 is currently on the Standards
      Track as a Proposed Standard, and is listed in Assigned Numbers
      [18].

Murphy, Rieth & Stevens                                        [Page 38]