Telnet Options

TELNET OPTIONS

The Telnet Protocol has a number of options that may be negotiated.
These options are listed here.  "Internet Official Protocol Standards"
(STD 1) provides more detailed information.

Options  Name                                              References
-------  -----------------------                           ----------
   0     Binary Transmission                                 [RFC856]
   1     Echo                                                [RFC857]
   2     Reconnection                                      [NIC50005]
   3     Suppress Go Ahead                                   [RFC858]
   4     Approx Message Size Negotiation                   [ETHERNET]
   5     Status                                              [RFC859]
   6     Timing Mark                                         [RFC860]
   7     Remote Controlled Trans and Echo                    [RFC726]
   8     Output Line Width                                 [NIC50005]
   9     Output Page Size                                  [NIC50005]
  10     Output Carriage-Return Disposition                  [RFC652]
  11     Output Horizontal Tab Stops                         [RFC653]
  12     Output Horizontal Tab Disposition                   [RFC654]
  13     Output Formfeed Disposition                         [RFC655]
  14     Output Vertical Tabstops                            [RFC656]
  15     Output Vertical Tab Disposition                     [RFC657]
  16     Output Linefeed Disposition                         [RFC657]
  17     Extended ASCII                                      [RFC698]
  18     Logout                                              [RFC727]
  19     Byte Macro                                          [RFC735]
  20     Data Entry Terminal                         [RFC1043,RFC732]
  21     SUPDUP                                       [RFC736,RFC734]
  22     SUPDUP Output                                       [RFC749]
  23     Send Location                                       [RFC779]
  24     Terminal Type                                      [RFC1091]
  25     End of Record                                       [RFC885]
  26     TACACS User Identification                          [RFC927]
  27     Output Marking                                      [RFC933]
  28     Terminal Location Number                            [RFC946]
  29     Telnet 3270 Regime                                 [RFC1041]
  30     X.3 PAD                                            [RFC1053]
  31     Negotiate About Window Size                  [RFC1073,DW183]
  32     Terminal Speed                                     [RFC1079]
  33     Remote Flow Control                                [RFC1372]
  34     Linemode                                           [RFC1184]
  35     X Display Location                                 [RFC1096]
  36     Environment Option                                 [RFC1408]
  37     Authentication Option                              [RFC1416]
  38     Encryption Option                                   [Borman]
  39     New Environment Option                             [RFC1572]
  40     TN3270E                                            [RFC1647]
  41     XAUTH                                              [Earhart]
 255     Extended-Options-List                               [RFC861]

Telnet Authentication Types

In [RFC1416], a list of authentication types is introduced.  Additions
to the list are registerd by the IANA and documented here.

Type       Description                  Reference
  0        NULL                         [RFC1416]
  1        KERBEROS_V4                  [RFC1416]
  2        KERBEROS_V5                  [RFC1416]
  3        SPX                          [RFC1416]
  4-5      Unassigned                      [IANA]
  6        RSA                          [RFC1416]
  7-9      Unassigned                      [IANA]
 10        LOKI                         [RFC1416]
 11        SSA                           [Schoch]

In [RFC 1411], on the KERBEROS_V4 Telnet Authentication type there are
a set of Suboption Commands.  Additions to the list are registerd by
the IANA and documented here.

Suboption	Command                  Reference
   0            AUTH                     [RFC1411]
   1            REJECT                   [RFC1411]
   2            ACCEPT                   [RFC1411]
   3            CHALLENGE                [RFC1411]
   4            RESPONSE                 [RFC1411]
   5            FORWARD                 [Brashear]
   6            FORWARD-ACCEPT          [Brashear]
   7            FORWARD-REJECT          [Brashear]


REFERENCES

[ETHERNET] "The Ethernet, A Local Area Network: Data Link Layer and
           Physical Layer Specification", AA-K759B-TK, Digital
           Equipment Corporation, Maynard, MA.  Also as: "The
           Ethernet - A Local Area Network", Version 1.0, Digital
           Equipment Corporation, Intel Corporation, Xerox
           Corporation, September 1980.  And: "The Ethernet, A Local
           Area Network: Data Link Layer and Physical Layer
           Specifications", Digital, Intel and Xerox, November 1982.
           And: XEROX, "The Ethernet, A Local Area Network: Data Link
           Layer and Physical Layer Specification", X3T51/80-50, Xerox
           Corporation, Stamford, CT., October 1980.

[NIC50005] DDN Protocol Handbook, "Telnet Reconnection Option",
           "Telnet Output Line Width Option", "Telnet Output Page Size
           Option", NIC 50005, December 1985.

[RFC652] Crocker, D., "Telnet Output Carriage-Return Disposition
         Option", RFC 652, UCLA-NMC, October 1974.

[RFC653] Crocker, D., "Telnet Output Horizontal Tabstops Option",
         RFC 653, UCLA-NMC, October 1974.

[RFC654] Crocker, D., "Telnet Output Horizontal Tab Disposition
         Option", RFC 654, UCLA-NMC, October 1974.

[RFC655] Crocker, D., "Telnet Output Formfeed Disposition Option",
         RFC 655, UCLA-NMC, October 1974.

[RFC656] Crocker, D., "Telnet Output Vertical Tabstops Option",
         RFC 656, UCLA-NMC, October 1974.

[RFC657] Crocker, D., "Telnet Output Vertical Tab Disposition Option",
         RFC 657, UCLA-NMC, October 1974.

[RFC658] Crocker, D., "Telnet Output Linefeed Disposition", RFC 658,
         UCLA-NMC, October 1974.

[RFC698] Tovar, "Telnet Extended ASCII Option", RFC 698, Stanford
         University-AI, July 1975.

[RFC726] Postel, J. and D. Crocker, "Remote Controlled Transmission
         and Echoing Telnet Option", RFC 726, SRI-ARC, UC Irvine,
         March 1977.

[RFC727] Crispin, M., "Telnet Logout Option", RFC 727, Stanford
         University-AI, April 1977.

[RFC734] Crispin, M., "SUPDUP Protocol", RFC 734, Stanford,
         October 1977.

[RFC735] Crocker, D. and R. Gumpertz, "Revised Telnet Byte Marco
         Option", RFC 735, Rand, CMU, November 1977.

[RFC736] Crispin, M., "Telnet SUPDUP Option", Stanford University-AI,
         RFC 736, Stanford, October 1977.

[RFC749] Greenberg, B., "Telnet SUPDUP-OUTPUT Option", RFC 749,
         MIT-Multics, September 1978.

[RFC779] Killian, E., "Telnet Send-Location Option", RFC 779,
         LLL, April 1981.

[RFC856] Postel, J. and J. Reynolds, "Telnet Binary Transmission",
         STD 27, RFC 856, USC/Information Sciences Institute, May
         1983.

[RFC857] Postel, J. and J. Reynolds, "Telnet Echo Option", STD 28, RFC
         857, USC/Information Sciences Institute, May 1983.

[RFC858] Postel, J. and J. Reynolds, "Telnet Suppress Go Ahead
         Option", STD 29, RFC 858, USC/Information Sciences Institute,
         May 1983.

[RFC859] Postel, J. and J. Reynolds, "Telnet Status Option", STD 30,
         RFC 859, USC/Information Sciences Institute, May 1983.

[RFC860] Postel, J. and J. Reynolds, "Telnet Timing Mark Option",
         STD 31, RFC 860, USC/Information Sciences Institute, May
         1983.

[RFC861] Postel, J. and J. Reynolds, "Telnet Extended Options - List
         Option", STD 32, RFC 861, USC/Information Sciences Institute,
         May 1983.

[RFC885] Postel, J., "Telnet End of Record Option", RFC 885,
         USC/Information Sciences Institute, December 1983.

[RFC927] Anderson, B., "TACACS User Identification Telnet Option",
         RFC 927, BBN, December 1984.

[RFC933] Silverman, S., "Output Marking Telnet Option", RFC 933,
         MITRE, January 1985.

[RFC946] Nedved, R., "Telnet Terminal Location Number Option",
         RFC 946, Carnegie-Mellon University, May 1985.

[RDC1041] Rekhter, J., "Telnet 3270 Regime Option", RFC 1041,
          IBM, January 1988.

[RFC1043] Yasuda, A., and T. Thompson, "TELNET Data Entry Terminal
          Option DODIIS Implementation", RFC 1043, DIA, February 1988.

[RFC1053] Levy, S., and T. Jacobson, "Telnet X.3 PAD Option",
          RFC 1053, Minnesota Supercomputer Center, April 1988.

[RFC1073] Waitzman, D., "Telnet Window Size Option", RFC 1073,
          BBN STC, October, 1988.

[RFC1079] Hedrick, C., "Telnet Terminal Speed Option", RFC 1079,
          Rutgers University, December 1988.

[RFC1091] VanBokkelen, J., "Telnet Terminal Type Option",
          RFC 1091, FTP Software, Inc., February 1989.

[RFC1096] Marcy, G., "Telnet X Display Location Option", RFC 1096,
          Carnegie Mellon University, March 1989.

[RFC1184] Borman, D., Editor, "Telnet Linemode Option",
          RFC 1184, Cray Research, Inc., October 1990.

[RFC1372] Hedrick, C., and D. Borman, "Telnet Remote Flow Control
         Option", RFC 1372, Rutgers University, Cray Research, Inc.,
         October 1992.

[RFC1408] Borman, D., Editor, "Telnet Environment Option", RFC 1408,
          Cray Research, Inc., January 1993.

[RFC1411] Borman, D., Editor, "Telnet Authentication: Kerberos 
          Version 4", RFC 1411, Cray Research, Inc., January 1993.

[RFC1416] Borman, D., Editor, "Telnet Authentication Option", RFC
          1416, Cray Research, Inc., February 1993.

[RFC1572] Alexander, S., Editor, "Telnet Environment Option", RFC1572,
          Lachman Technology, Inc., January 1994.

[RFC1647] Kelly, B., "TN3270 Enhancements", RFC1647, Auburn
          University, July 1994.


PEOPLE

[Brashear] Derrick Brashear, <shadow@dementia.org>, January 1995.

[Borman] Dave Borman, <dab@CRAY.COM>, January 1995.

[Earhart] Rob Earhart, <earhart+@CMU.EDU>, April 1995.

[IANA] Internet Assigned Numbers Authority, <iana@isi.edu>, January
1995.

[Schoch]  Steven Schoch, <schoch@sheba.arc.nasa.gov>, January 1995.


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