    Network Working Group                                        J. Reynolds
    Request for Comments: 924                                      J. Postel
                                                                         ISI
    Obsoletes: RFCs 901, 880, 840                               October 1984

                        OFFICIAL ARPA-INTERNET PROTOCOLS

    STATUS OF THIS MEMO

       This memo is an official status report on the protocols used in the
       ARPA-Internet community.  Distribution of this memo is unlimited.

    INTRODUCTION

       This RFC identifies the documents specifying the official protocols
       used in the Internet.  Comments indicate any revisions or changes
       planned.

       To first order, the official protocols are those in the "Internet
       Protocol Transition Workbook" (IPTW) dated March 1982.  There are
       several protocols in use that are not in the IPTW.  A few of the
       protocols in the IPTW have been revised.  Notably, the mail protocols
       have been revised and issued as a volume titled "Internet Mail
       Protocols" dated November 1982.  Telnet and the most useful Telnet
       options have been revised and issued as a volume titled "Internet
       Telnet Protocol and Options" (ITP) dated June 1983.  Some protocols
       have not been revised for many years, these are found in the old
       "ARPANET Protocol Handbook" (APH) dated January 1978.  There is also
       a volume of protocol related information called the "Internet
       Protocol Implementers Guide" (IPIG) dated August 1982.

       This document is organized as a sketchy outline.  The entries are
       protocols (e.g., Transmission Control Protocol).  In each entry there
       are notes on status, specification, comments, other references,
       dependencies, and contact.

          The STATUS is one of: required, recommended, elective, or
          experimental.

          The SPECIFICATION identifies the protocol defining documents.

          The COMMENTS describe any differences from the specification or
          problems with the protocol.

          The OTHER REFERENCES identify documents that comment on or expand
          on the protocol.

          The DEPENDENCIES indicate what other protocols are called upon by
          this protocol.

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    Official ARPA-Internet Protocols                                 RFC 924

          The CONTACT indicates a person who can answer questions about the
          protocol.

          In particular, the status may be:

             required

                - all hosts must implement the required protocol,

             recommended

                - all hosts are encouraged to implement the recommended
                protocol,

             elective

                - hosts may implement or not the elective protocol,

             experimental

                - hosts should not implement the experimental protocol
                unless they are participating in the experiment and have
                coordinated their use of this protocol with the contact
                person, and

             none

                - this is not a protocol.

             For further information about protocols in general, please
             contact:

                Joyce Reynolds
                USC - Information Sciences Institute
                4676 Admiralty Way
                Marina del Rey, California  90292-6695

                Phone: (213) 822-1511

                ARPA mail: JKREYNOLDS@USC-ISIF.ARPA

    Reynolds & Postel                                               [Page 2]

    Official ARPA-Internet Protocols                                 RFC 924

    OVERVIEW

       Catenet Model  ------------------------------------------------------

          STATUS:  None

          SPECIFICATION:  IEN 48 (in IPTW)

          COMMENTS:

             Gives an overview of the organization and principles of the
             Internet.

             Could be revised and expanded.

          OTHER REFERENCES:

             RFC 871 - A Perspective on the ARPANET Reference Model

          DEPENDENCIES:

          CONTACT: Postel@USC-ISIF.ARPA

    Reynolds & Postel                                               [Page 3]

    Official ARPA-Internet Protocols                                 RFC 924

    NETWORK LEVEL

       Internet Protocol  --------------------------------------------- (IP)

          STATUS:  Required

          SPECIFICATION:  RFC 791 (in IPTW)

          COMMENTS:

             This is the universal protocol of the Internet.  This datagram
             protocol provides the universal addressing of hosts in the
             Internet.

             A few minor problems have been noted in this document.

             The most serious is a bit of confusion in the route options.
             The route options have a pointer that indicates which octet of
             the route is the next to be used.  The confusion is between the
             phrases "the pointer is relative to this option" and "the
             smallest legal value for the pointer is 4".  If you are
             confused, forget about the relative part, the pointer begins
             at 4.

             Another important point is the alternate reassembly procedure
             suggested in RFC 815.

             Note that ICMP is defined to be an integral part of IP.  You
             have not completed an implementation of IP if it does not
             include ICMP.

          OTHER REFERENCES:

             RFC 815 (in IPIG) - IP Datagram Reassembly Algorithms

             RFC 814 (in IPIG) - Names, Addresses, Ports, and Routes

             RFC 816 (in IPIG) - Fault Isolation and Recovery

             RFC 817 (in IPIG) - Modularity and Efficiency in Protocol
             Implementation

             MIL-STD-1777 - Military Standard Internet Protocol

          DEPENDENCIES:

          CONTACT: Postel@USC-ISIF.ARPA

    Reynolds & Postel                                               [Page 4]

    Official ARPA-Internet Protocols                                 RFC 924

       Internet Control Message Protocol  --------------------------- (ICMP)

          STATUS:  Required

          SPECIFICATION:  RFC 792 (in IPTW)

          COMMENTS:

             The control messages and error reports that go with the
             Internet Protocol.

             A few minor errors in the document have been noted.
             Suggestions have been made for additional types of redirect
             message and additional destination unreachable messages.

             A proposal for two additional ICMP message types  is made in
             RFC 917 "Internet Subnets", Address Format Request (A1=17), and
             Address Format Reply (A2=18).  Use of these ICMP types is
             experimental.

             Note that ICMP is defined to be an integral part of IP.  You
             have not completed an implementation of IP if it does not
             include ICMP.

          OTHER REFERENCES:  RFC 917

          DEPENDENCIES: Internet Protocol

          CONTACT: Postel@USC-ISIF.ARPA

    Reynolds & Postel                                               [Page 5]

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    HOST LEVEL

       User Datagram Protocol  --------------------------------------- (UDP)

          STATUS:  Recommended

          SPECIFICATION:  RFC 768 (in IPTW)

          COMMENTS:

             Provides a datagram service to applications.  Adds port
             addressing to the IP services.

             The only change noted for the UDP specification is a minor
             clarification that if in computing the checksum a padding octet
             is used for the computation it is not transmitted or counted in
             the length.

          OTHER REFERENCES:

          DEPENDENCIES: Internet Protocol

          CONTACT: Postel@USC-ISIF.ARPA

       Transmission Control Protocol  -------------------------------- (TCP)

          STATUS:  Recommended

          SPECIFICATION:  RFC 793 (in IPTW)

          COMMENTS:

             Provides reliable end-to-end data stream service.

             Many comments and corrections have been received for the TCP
             specification document.  These are primarily document bugs
             rather than protocol bugs.

             Event Processing Section:  There are many minor corrections and
             clarifications needed in this section.

             Push:  There are still some phrases in the document that give a
             "record mark" flavor to the push.  These should be further
             clarified.  The push is not a record mark.

             Urgent:  Page 17 is wrong.  The urgent pointer points to the
             last octet of urgent data (not to the first octet of non-ungent
             data).

    Reynolds & Postel                                               [Page 6]

    Official ARPA-Internet Protocols                                 RFC 924

             Listening Servers:  Several comments have been received on
             difficulties with contacting listening servers.  There should
             be some discussion of implementation issues for servers, and
             some notes on alternative models of system and process
             organization for servers.

             Maximum Segment Size:  The maximum segment size option should
             be generalized and clarified.  It can be used to either
             increase or decrease the maximum segment size from the default.
             The TCP Maximum Segment Size is the IP Maximum Datagram Size
             minus forty.  The default IP Maximum Datagram Size if 576.  The
             default TCP Maximum Segment Size is 536.  For further
             discussion, see RFC 879.

             Idle Connections:  There have been questions about
             automatically closing idle connections.  Idle connections are
             ok, and should not be closed.  There are several cases where
             idle connections arise, for example, in Telnet when a user is
             thinking for a long time following a message from the server
             computer before his next input.  There is no TCP "probe"
             mechanism, and none is needed.

             Queued Receive Data on Closing:  There are several points where
             it is not clear from the description what to do about data
             received by the TCP but not yet passed to the user,
             particularly when the connection is being closed.  In general,
             the data is to be kept to give to the user if he does a RECV
             call.

             Out of Order Segments:  The description says that segments that
             arrive out of order, that is, are not exactly the next segment
             to be processed, may be kept on hand.  It should also point out
             that there is a very large performance penalty for not doing
             so.

             User Time Out:  This is the time out started on an open or send
             call.  If this user time out occurs the user should be
             notified, but the connection should not be closed or the TCB
             deleted.  The user should explicitly ABORT the connection if he
             wants to give up.

          OTHER REFERENCES:

             RFC 813 (in IPIG) - Window and Acknowledgement Strategy in TCP

             RFC 814 (in IPIG) - Names, Addresses, Ports, and Routes

             RFC 816 (in IPIG) - Fault Isolation and Recovery

    Reynolds & Postel                                               [Page 7]

    Official ARPA-Internet Protocols                                 RFC 924

             RFC 817 (in IPIG) - Modularity and Efficiency in Protocol
             Implementation

             RFC 879 - TCP Maximum Segment Size

             RFC 889 - Internet Delay Experiments

             RFC 896 - TCP/IP Congestion Control

             MIL-STD-1778 - Military Standard Transmission Control Protocol

          DEPENDENCIES: Internet Protocol

          CONTACT: Postel@USC-ISIF.ARPA

       Host Monitoring Protocol  ------------------------------------- (HMP)

          STATUS:  Elective

          SPECIFICATION:  RFC 869

          COMMENTS:

             This is a good tool for debugging protocol implementations in
             remotely located computers.

             This protocol is used to monitor Internet gateways and the
             TACs.

          OTHER REFERENCES:

          DEPENDENCIES: Internet Protocol

          CONTACT: Hinden@BBN-UNIX.ARPA

       Cross Net Debugger  ------------------------------------------ (XNET)

          STATUS:  Elective

          SPECIFICATION:  IEN 158

          COMMENTS:

             A debugging protocol, allows debugger like access to remote
             systems.

             This specification should be updated and reissued as an RFC.

          OTHER REFERENCES:  RFC 643

    Reynolds & Postel                                               [Page 8]

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          DEPENDENCIES: Internet Protocol

          CONTACT: Postel@USC-ISIF.ARPA

       "Stub" Exterior Gateway Protocol  ----------------------------- (EGP)

          STATUS:  Recommended for Gateways

          SPECIFICATION:  RFC 888, RFC 904

          COMMENTS:

             The protocol used between gateways of different administrations
             to exchange routing information.

             Please discuss any plans for implementation or use of this
             protocol with the contact.

          OTHER REFERENCES:  RFC 827, RFC 890

          DEPENDENCIES: Internet Protocol

          CONTACT: Mills@USC-ISID.ARPA

       Gateway Gateway Protocol  ------------------------------------- (GGP)

          STATUS:  Experimental

          SPECIFICATION:  RFC 823

          COMMENTS:

             The gateway protocol now used in the core gateways.

             Please discuss any plans for implementation or use of this
             protocol with the contact.

          OTHER REFERENCES:

          DEPENDENCIES: Internet Protocol

          CONTACT: Brescia@BBN-UNIX.ARPA

    Reynolds & Postel                                               [Page 9]

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       Multiplexing Protocol  ---------------------------------------- (MUX)

          STATUS:  Experimental

          SPECIFICATION:  IEN 90

          COMMENTS:

             Defines a capability to combine several segments from different
             higher level protocols in one IP datagram.

             No current experiment in progress.  There is some question as
             to the extent to which the sharing this protocol envisions can
             actually take place.  Also, there are some issues about the
             information captured in the multiplexing header being (a)
             insufficient, or (b) over specific.

             Please discuss any plans for implementation or use of this
             protocol with the contact.

          OTHER REFERENCES:

          DEPENDENCIES: Internet Protocol

          CONTACT: Postel@USC-ISIF.ARPA

       Stream Protocol  ----------------------------------------------- (ST)

          STATUS:  Experimental

          SPECIFICATION:  IEN 119

          COMMENTS:

             A gateway resource allocation protocol designed for use in
             multihost real time applications.

             The implementation of this protocol has evolved and may no
             longer be consistent with this specification.  The document
             should be updated and issued as an RFC.

             Please discuss any plans for implementation or use of this
             protocol with the contact.

          OTHER REFERENCES:

          DEPENDENCIES: Internet Protocol

          CONTACT: jwf@LL-EN.ARPA

    Reynolds & Postel                                              [Page 10]

    Official ARPA-Internet Protocols                                 RFC 924

       Network Voice Protocol  ------------------------------------ (NVP-II)

          STATUS:  Experimental

          SPECIFICATION:  ISI Internal Memo

          COMMENTS:

             Defines the procedures for real time voice conferencing.

             The specification is an ISI Internal Memo which should be
             updated and issued as an RFC.

             Please discuss any plans for implementation or use of this
             protocol with the contact.

          OTHER REFERENCES:  RFC 741

          DEPENDENCIES:  Internet Protocol, Stream Protocol

          CONTACT:  Casner@USC-ISIB.ARPA

       Reliable Data Protocol  --------------------------------------- (RDP)

          STATUS:  Experimental

          SPECIFICATION:  RFC 908

          COMMENTS:

             This protocol is designed to efficiently support the bulk
             transfer of data for such host monitoring and control
             applications as loading/dumping and remote debugging.  The
             protocol is intended to be simple to implement but still be
             efficient in environments where there may be long transmission
             delays and loss or non-sequential delivery of message segments.

          OTHER REFERENCES:

          DEPENDENCIES:  Internet Protocol

          CONTACT:  CWelles@BBN-UNIX.ARPA

    Reynolds & Postel                                              [Page 11]

    Official ARPA-Internet Protocols                                 RFC 924

    APPLICATION LEVEL

       Telnet Protocol  ------------------------------------------- (TELNET)

          STATUS:  Recommended

          SPECIFICATION:  RFC 854 (in "Internet Telnet Protocol and
          Options")

          COMMENTS:

             The protocol for remote terminal access.

             This has been revised since the IPTW.  RFC 764 in IPTW is now
             obsolete.

          OTHER REFERENCES:

             MIL-STD-1782 - Telnet Protocol and Options (TELNET)

          DEPENDENCIES:  Transmission Control Protocol

          CONTACT:  Postel@USC-ISIF.ARPA

    Reynolds & Postel                                              [Page 12]

    Official ARPA-Internet Protocols                                 RFC 924

       Telnet Options  ------------------------------------ (TELNET-OPTIONS)

          STATUS:  Elective

          SPECIFICATION:  General description of options:  RFC 855
          (in "Internet Telnet Protocol and Options")

          Number   Name                                RFC  NIC  ITP APH USE
          ------   ---------------------------------   --- ----- --- --- ---
             0     Binary Transmission                 856 ----- yes obs yes
             1     Echo                                857 ----- yes obs yes
             2     Reconnection                        ... 15391  no yes  no
             3     Suppress Go Ahead                   858 ----- yes obs yes
             4     Approx Message Size Negotiation     ... 15393  no yes  no
             5     Status                              859 ----- yes obs yes
             6     Timing Mark                         860 ----- yes obs yes
             7     Remote Controlled Trans and Echo    726 39237  no yes  no
             8     Output Line Width                   ... 20196  no yes  no
             9     Output Page Size                    ... 20197  no yes  no
            10     Output Carriage-Return Disposition  652 31155  no yes  no
            11     Output Horizontal Tabstops          653 31156  no yes  no
            12     Output Horizontal Tab Disposition   654 31157  no yes  no
            13     Output Formfeed Disposition         655 31158  no yes  no
            14     Output Vertical Tabstops            656 31159  no yes  no
            15     Output Vertical Tab Disposition     657 31160  no yes  no
            16     Output Linefeed Disposition         658 31161  no yes  no
            17     Extended ASCII                      698 32964  no yes  no
            18     Logout                              727 40025  no yes  no
            19     Byte Macro                          735 42083  no yes  no
            20     Data Entry Terminal                 732 41762  no yes  no
            21     SUPDUP                          734 736 42213  no yes  no
            22     SUPDUP Output                       749 45449  no  no  no
            23     Send Location                       779 -----  no  no  no
            24     Terminal Type                       884 -----  no  no yes
            25     End of Record                       885 -----  no  no yes
           255     Extended-Options-List               861 ----- yes obs yes

                                                            (obs = obsolete)

          The ITP column indicates if the specification is included in the
          Internet Telnet Protocol and Options.  The APH column indicates if
          the specification is included in the ARPANET Protocol Handbook.
          The USE column of the table above indicates which options are in
          general use.

          COMMENTS:

             The Binary Transmission, Echo, Suppress Go Ahead, Status,
             Timing Mark, and Extended Options List options have been

    Reynolds & Postel                                              [Page 13]

    Official ARPA-Internet Protocols                                 RFC 924

             recently updated and reissued.  These are the most frequently
             implemented options.

             The remaining options should be reviewed and the useful ones
             should be revised and reissued.  The others should be
             eliminated.

             The following are recommended:  Binary Transmission, Echo,
             Suppress Go Ahead, Status, Timing Mark, and Extended Options
             List.

          OTHER REFERENCES:

          DEPENDENCIES: Telnet

          CONTACT: Postel@USC-ISIF.ARPA

       File Transfer Protocol  --------------------------------------- (FTP)

          STATUS:  Recommended

          SPECIFICATION:  RFC 765 (in IPTW)

          COMMENTS:

             The protocol for moving files between Internet hosts.  Provides
             for access control and negotiation of file parameters.

             There are a number of minor corrections to be made.  A major
             change is the deletion of the mail commands, and a major
             clarification is needed in the discussion of the management of
             the data connection.  Also, a suggestion has been made to
             include some directory manipulation commands (RFC 775).

             Even though the MAIL features are defined in this document,
             they are not to be used.  The SMTP protocol is to be used for
             all mail service in the Internet.

             Data Connection Management:

                a.  Default Data Connection Ports:  All FTP implementations
                must support use of the default data connection ports, and
                only the User-PI may initiate the use of non-default ports.

                b.  Negotiating Non-Default Data Ports:   The User-PI may
                specify a non-default user side data port with the PORT
                command.  The User-PI may request the server side to
                identify a non-default server side data port with the PASV
                command.  Since a connection is defined by the pair of

    Reynolds & Postel                                              [Page 14]

    Official ARPA-Internet Protocols                                 RFC 924

                addresses, either of these actions is enough to get a
                different data connection, still it is permitted to do both
                commands to use new ports on both ends of the data
                connection.

                c.  Reuse of the Data Connection:  When using the stream
                mode of data transfer the end of the file must be indicated
                by closing the connection.  This causes a problem if
                multiple files are to be transfered in the session, due to
                need for TCP to hold the connection record for a time out
                period to guarantee the reliable communication.  Thus the
                connection can not be reopened at once.

                   There are two solutions to this problem.  The first is to
                   negotiate a non-default port (as in (b) above).  The
                   second is to use another transfer mode.

                   A comment on transfer modes.  The stream transfer mode is
                   inherently unreliable, since one can not determine if the
                   connection closed prematurely or not.  The other transfer
                   modes (Block, Compressed) do not close the connection to
                   indicate the end of file.  They have enough FTP encoding
                   that the data connection can be parsed to determine the
                   end of the file.  Thus using these modes one can leave
                   the data connection open for multiple file transfers.

                   Why this was not a problem with the old NCP FTP:

                      The NCP was designed with only the ARPANET in mind.
                      The ARPANET provides very reliable service, and the
                      NCP counted on it.  If any packet of data from an NCP
                      connection were lost or damaged by the network the NCP
                      could not recover.  It is a tribute to the ARPANET
                      designers that the NCP FTP worked so well.

                      The TCP is designed to provide reliable connections
                      over many different types of networks and
                      interconnections of networks.  TCP must cope with a
                      set of networks that can not promise to work as well
                      as the ARPANET.  TCP must make its own provisions for
                      end-to-end recovery from lost or damaged packets.
                      This leads to the need for the connection phase-down
                      time-out.  The NCP never had to deal with
                      acknowledgements or retransmissions or many other
                      things the TCP must do to make connection reliable in
                      a more complex world.

    Reynolds & Postel                                              [Page 15]

    Official ARPA-Internet Protocols                                 RFC 924

             LIST and NLST:

                There is some confusion about the LIST an NLST commands, and
                what is appropriate to return.  Some clarification and
                motivation for these commands should be added to the
                specification.

          OTHER REFERENCES:

             RFC 678 - Document File Format Standards

             MIL-STD-1780 - File Transfer Protocol (FTP)

          DEPENDENCIES: Transmission Control Protocol

          CONTACT: Postel@USC-ISIF.ARPA

       Trivial File Transfer Protocol  ------------------------------ (TFTP)

          STATUS:  Elective

          SPECIFICATION:  RFC 783 (in IPTW)

          COMMENTS:

             A very simple file moving protocol, no access control is
             provided.

             This is in use in several local networks.

             Ambiguities in the interpretation of several of the transfer
             modes should be  clarified, and additional transfer modes could
             be defined.  Additional error codes could be defined to more
             clearly identify problems.

          OTHER REFERENCES:

          DEPENDENCIES: User Datagram Protocol

          CONTACT: Postel@USC-ISIF.ARPA

    Reynolds & Postel                                              [Page 16]

    Official ARPA-Internet Protocols                                 RFC 924

       Simple File Transfer Protocol  ------------------------------- (SFTP)

          STATUS:  Experimental

          SPECIFICATION:  RFC 913

          COMMENTS:

             SFTP is a simple file transfer protocol.  It fills the need of
             people wanting a protocol that is more useful than TFTP but
             easier to implement (and less powerful) than FTP.  SFTP
             supports user access control, file transfers, directory
             listing, directory changing, file renaming and deleting.

             SFTP can be implemented with any reliable 8-bit byte stream
             oriented protocol, this document describes its TCP
             specification.  SFTP uses only one TCP connection; whereas TFTP
             implements a connection over UDP, and FTP uses two TCP
             connections (one using the TELNET protocol).

             Please discuss any plans for implementation or use of this
             protocol with the contact.

          OTHER REFERENCES:

          DEPENDENCIES: Transmission Control Protocol

          CONTACT: MKL@MIT-XX.ARPA

       Simple Mail Transfer Protocol  ------------------------------- (SMTP)

          STATUS:  Recommended

          SPECIFICATION:  RFC 821 (in "Internet Mail Protocols")

          COMMENTS:

             The procedure for transmitting computer mail between hosts.

             This has been revised since the IPTW, it is in the "Internet
             Mail Protocols" volume of November 1982.  RFC 788 (in IPTW) is
             obsolete.

             There have been many misunderstandings and errors in the early
             implementations.  Some documentation of these problems can be
             found in the file [ISIF]<SMTP>MAIL.ERRORS.

             Some minor differences between RFC 821 and RFC 822 should be
             resolved.

    Reynolds & Postel                                              [Page 17]

    Official ARPA-Internet Protocols                                 RFC 924

          OTHER REFERENCES:

             RFC 822 - Mail Header Format Standards

                This has been revised since the IPTW, it is in the "Internet
                Mail Protocols" volume of November 1982.  RFC 733 (in IPTW)
                is obsolete.  Further revision of RFC 822 is needed to
                correct some minor errors in the details of the
                specification.

             MIL-STD-1781 - Simple Mail Transfer Protocol (SMTP)

          DEPENDENCIES: Transmission Control Protocol

          CONTACT: Postel@USC-ISIF.ARPA

       Resource Location Protocol  ----------------------------------- (RLP)

          STATUS:   Elective

          SPECIFICATION:   RFC 887

          COMMENTS:

             A resource location protocol for use in the ARPA-Internet.
             This protocol utilizes the User Datagram Protocol (UDP) which
             in turn calls on the Internet Protocol to deliver its
             datagrams.

          OTHER REFERENCES:

          DEPENDENCIES: User Datagram Protocol

          CONTACT:   Accetta@CMU-CS-A.ARPA

       Loader Debugger Protocol  ------------------------------------- (LDP)

          STATUS:  Experimental

          SPECIFICATION:  RFC 909

          COMMENTS:

             Specifies a protocol for loading, dumping and debugging target
             machines from hosts in a network environment.  It is also
             designed to accommodate a variety of target CPU types.  It
             provides a powerful set of debugging services, while at the
             same time, it is structured so that a simple subset may be

    Reynolds & Postel                                              [Page 18]

    Official ARPA-Internet Protocols                                 RFC 924

             implemented in applications like boot loading where efficiency
             and space are at a premium.

          OTHER REFERENCES:

          DEPENDENCIES:  Reliable Data Protocol

          CONTACT:  Hinden@BBN-UNIX.ARPA

       Remote Job Entry  --------------------------------------------- (RJE)

          STATUS:  Elective

          SPECIFICATION:  RFC 407 (in APH)

          COMMENTS:

             The general protocol for submitting batch jobs and retrieving
             the results.

             Some changes needed for use with TCP.

             No known active implementations.

          OTHER REFERENCES:

          DEPENDENCIES: File Transfer Protocol
                        Transmission Control Protocol

          CONTACT: Postel@USC-ISIF.ARPA

       Remote Job Service  ---------------------------------------- (NETRJS)

          STATUS:  Elective

          SPECIFICATION:  RFC 740 (in APH)

          COMMENTS:

             A special protocol for submitting batch jobs and retrieving the
             results used with the UCLA IBM OS system.

             Please discuss any plans for implementation or use of this
             protocol with the contact.

             Revision in progress.

          OTHER REFERENCES:

    Reynolds & Postel                                              [Page 19]

    Official ARPA-Internet Protocols                                 RFC 924

          DEPENDENCIES: Transmission Control Protocol

          CONTACT: Braden@USC-ISIA.ARPA

       Remote Telnet Service  ------------------------------------ (RTELNET)

          STATUS:  Elective

          SPECIFICATION:  RFC 818

          COMMENTS:

             Provides special access to user Telnet on a remote system.

          OTHER REFERENCES:

          DEPENDENCIES: Telnet, Transmission Control Protocol

          CONTACT: Postel@USC-ISIF.ARPA

       Graphics Protocol  --------------------------------------- (GRAPHICS)

          STATUS:  Elective

          SPECIFICATION:  NIC 24308 (in APH)

          COMMENTS:

             The protocol for vector graphics.

             Very minor changes needed for use with TCP.

             No known active implementations.

          OTHER REFERENCES:

          DEPENDENCIES: Telnet, Transmission Control Protocol

          CONTACT: Postel@USC-ISIF.ARPA

    Reynolds & Postel                                              [Page 20]

    Official ARPA-Internet Protocols                                 RFC 924

       Echo Protocol  ----------------------------------------------- (ECHO)

          STATUS:  Recommended

          SPECIFICATION:  RFC 862

          COMMENTS:

             Debugging protocol, sends back whatever you send it.

          OTHER REFERENCES:

          DEPENDENCIES: Transmission Control Protocol
                        or User Datagram Protocol

          CONTACT: Postel@USC-ISIF.ARPA

       Discard Protocol  ----------------------------------------- (DISCARD)

          STATUS:  Elective

          SPECIFICATION:  RFC 863

          COMMENTS:

             Debugging protocol, throws away whatever you send it.

          OTHER REFERENCES:

          DEPENDENCIES: Transmission Control Protocol
                        or User Datagram Protocol

          CONTACT: Postel@USC-ISIF.ARPA

       Character Generator Protocol  ----------------------------- (CHARGEN)

          STATUS:  Elective

          SPECIFICATION:  RFC 864

          COMMENTS:

             Debugging protocol, sends you ASCII data.

          OTHER REFERENCES:

          DEPENDENCIES: Transmission Control Protocol
                        or User Datagram Protocol

    Reynolds & Postel                                              [Page 21]

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          CONTACT: Postel@USC-ISIF.ARPA

       Quote of the Day Protocol  ---------------------------------- (QUOTE)

          STATUS:  Elective

          SPECIFICATION:  RFC 865

          COMMENTS:

             Debugging protocol, sends you a short ASCII message.

          OTHER REFERENCES:

          DEPENDENCIES: Transmission Control Protocol
                        or User Datagram Protocol

          CONTACT: Postel@USC-ISIF.ARPA

       Active Users Protocol  -------------------------------------- (USERS)

          STATUS:  Elective

          SPECIFICATION:  RFC 866

          COMMENTS:

             Lists the currently active users.

          OTHER REFERENCES:

          DEPENDENCIES: Transmission Control Protocol
                        or User Datagram Protocol

          CONTACT: Postel@USC-ISIF.ARPA

       Authentication Service  -------------------------------------- (AUTH)

          STATUS:  Experimental

          SPECIFICATION:  RFC 912

          COMMENTS:

             The Authentication Server provides a means to determine the
             identity of a user of a particular TCP connection.  Given a TCP
             port number pair, it returns a character string which
             identifies the owner of that connection on the server's system.
             Suggested uses include automatic identification and

    Reynolds & Postel                                              [Page 22]

    Official ARPA-Internet Protocols                                 RFC 924

             verification of a user during an FTP session, additional
             verification of a TAC dial up user, and access verification for
             a generalized network file server.

             Please discuss any plans for implementation or use of this
             protocol with the contact.

          OTHER REFERENCES:

          DEPENDENCIES: Transmission Control Protocol

          CONTACT: StJohns@MIT-MULTICS.ARPA

       Finger Protocol  ------------------------------------------- (FINGER)

          STATUS:  Elective

          SPECIFICATION:  RFC 742 (in APH)

          COMMENTS:

             Provides information on the current or most recent activity of
             a user.

             Some extensions have been suggested.

             Some changes are are needed for TCP.

          OTHER REFERENCES:

          DEPENDENCIES: Transmission Control Protocol

          CONTACT: Postel@USC-ISIF.ARPA

       WhoIs Protocol  ------------------------------------------- (NICNAME)

          STATUS:  Elective

          SPECIFICATION:  RFC 812 (in IPTW)

          COMMENTS:

             Accesses the ARPANET Directory database.  Provides a way to
             find out about people, their addresses, phone numbers,
             organizations, and mailboxes.

          OTHER REFERENCES:

          DEPENDENCIES: Transmission Control Protocol

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    Official ARPA-Internet Protocols                                 RFC 924

          CONTACT: Feinler@SRI-NIC.ARPA

       Domain Name Protocol  -------------------------------------- (DOMAIN)

          STATUS:  Experimental

          SPECIFICATION:  RFC 881, 882, 883

          COMMENTS:

          OTHER REFERENCES:

             RFC 920 - Domain Requirements

             RFC 921 - Domain Name Implementation Schedule - Revised

          DEPENDENCIES: Transmission Control Protocol
                        or User Datagram Protocol

          CONTACT: Mockapetris@USC-ISIF.ARPA

       HOSTNAME Protocol  --------------------------------------- (HOSTNAME)

          STATUS:  Elective

          SPECIFICATION:  RFC 811 (in IPTW)

          COMMENTS:

             Accesses the Registered Internet Hosts database (HOSTS.TXT).
             Provides a way to find out about a host in the Internet, its
             Internet Address, and the protocols it implements.

          OTHER REFERENCES:

             RFC 810 - Host Table Specification

          DEPENDENCIES: Transmission Control Protocol

          CONTACT: Feinler@SRI-NIC.ARPA

    Reynolds & Postel                                              [Page 24]

    Official ARPA-Internet Protocols                                 RFC 924

       Host Name Server Protocol  ----------------------------- (NAMESERVER)

          STATUS:  Experimental

          SPECIFICATION:  IEN 116 (in IPTW)

          COMMENTS:

             Provides machine oriented procedure for translating a host name
             to an Internet Address.

             This specification has significant problems:  1) The name
             syntax is out of date.  2) The protocol details are ambiguous,
             in particular, the length octet either does or doesn't include
             itself and the op code.  3) The extensions are not supported by
             any known implementation.

             This protocol is now abandon in favor of the DOMAIN protocol.
             Further implementations of this protocol are not advised.

             Please discuss any plans for implementation or use of this
             protocol with the contact.

          OTHER REFERENCES:

          DEPENDENCIES: User Datagram Protocol

          CONTACT: Postel@USC-ISIF.ARPA

       CSNET Mailbox Name Server Protocol  ---------------------- (CSNET-NS)

          STATUS:  Experimental

          SPECIFICATION:  CS-DN-2

          COMMENTS:

             Provides access to the CSNET data base of users to give
             information about users names, affiliations, and mailboxes.

             Please discuss any plans for implementation or use of this
             protocol with the contact.

          OTHER REFERENCES:

          DEPENDENCIES: Transmission Control Protocol

          CONTACT: Solomon@UWISC.ARPA

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    Official ARPA-Internet Protocols                                 RFC 924

       Daytime Protocol  ----------------------------------------- (DAYTIME)

          STATUS:  Elective

          SPECIFICATION:  RFC 867

          COMMENTS:

             Provides the day and time in ASCII character string.

          OTHER REFERENCES:

          DEPENDENCIES: Transmission Control Protocol
                        or User Datagram Protocol

          CONTACT: Postel@USC-ISIF.ARPA

       Time Server Protocol  ---------------------------------------- (TIME)

          STATUS:  Recommended

          SPECIFICATION:  RFC 868

          COMMENTS:

             Provides the time as the number of seconds from a specified
             reference time.

          OTHER REFERENCES:

          DEPENDENCIES: Transmission Control Protocol
                        or User Datagram Protocol

          CONTACT: Postel@USC-ISIF.ARPA

    Reynolds & Postel                                              [Page 26]

    Official ARPA-Internet Protocols                                 RFC 924

       DCNET Time Server Protocol  --------------------------------- (CLOCK)

          STATUS:  Elective

          SPECIFICATION:  RFC 778

          COMMENTS:

             Provides a mechanism for keeping synchronized clocks.

          OTHER REFERENCES:

          DEPENDENCIES: Internet Control Message Protocol

          CONTACT: Mills@USC-ISID.ARPA

       SUPDUP Protocol  ------------------------------------------- (SUPDUP)

          STATUS:  Elective

          SPECIFICATION:  RFC 734 (in APH)

          COMMENTS:

             A special Telnet like protocol for display terminals.

          OTHER REFERENCES:

          DEPENDENCIES: Transmission Control Protocol

          CONTACT: Crispin@SU-SCORE.ARPA

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    Official ARPA-Internet Protocols                                 RFC 924

       Internet Message Protocol  ------------------------------------ (MPM)

          STATUS:  Experimental

          SPECIFICATION:  RFC 759

          COMMENTS:

             This is an experimental multimedia mail transfer protocol.  The
             implementation is called a Message Processing Module or MPM.

             Please discuss any plans for implementation or use of this
             protocol with the contact.

          OTHER REFERENCES:

             RFC 767 - Structured Document Formats

          DEPENDENCIES: Transmission Control Protocol

          CONTACT: Postel@USC-ISIF.ARPA

       Post Office Protocol  ----------------------------------------- (POP)

          STATUS:  Experimental

          SPECIFICATION:  RFC 918

          COMMENTS:

             The intent of the Post Office Protocol (POP) is to allow a
             user's workstation to access mail from a mailbox server.  It is
             expected that mail will be posted from the workstation to the
             mailbox server via the Simple Mail Transfer Protocol (SMTP).
             For further information see RFC-821 and RFC-822.

             Please discuss any plans for implementation or use of this
             protocol with the contact.

          OTHER REFERENCES:

          DEPENDENCIES: Transmission Control Protocol

          CONTACT: JKReynolds@USC-ISIF.ARPA

    Reynolds & Postel                                              [Page 28]

    Official ARPA-Internet Protocols                                 RFC 924

       Network Standard Text Editor  ------------------------------- (NETED)

          STATUS:  Elective

          SPECIFICATION:  RFC 569

          COMMENTS:

             Describes a simple line editor which could be provided by every
             Internet host.

          OTHER REFERENCES:

          DEPENDENCIES:

          CONTACT:  Postel@USC-ISIF.ARPA

    Reynolds & Postel                                              [Page 29]

    Official ARPA-Internet Protocols                                 RFC 924

    APPENDICES

       Assigned Numbers  ---------------------------------------------------

          STATUS:  None

          SPECIFICATION:  RFC 923

          COMMENTS:

             Describes the fields of various protocols that are assigned
             specific values for actual use, and lists the currently
             assigned values.

             Issued October 1984, replaces RFC 900, RFC 790 in IPTW, and
             RFC 870.

          OTHER REFERENCES:

          CONTACT: JKReynolds@USC-ISIF.ARPA

       Pre-emption  --------------------------------------------------------

          STATUS:  Elective

          SPECIFICATION:  RFC 794 (in IPTW)

          COMMENTS:

             Describes how to do pre-emption of TCP connections.

          OTHER REFERENCES:

          CONTACT: Postel@USC-ISIF.ARPA

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    Official ARPA-Internet Protocols                                 RFC 924

       Service Mappings  ---------------------------------------------------

          STATUS:  None

          SPECIFICATION:  RFC 795 (in IPTW)

          COMMENTS:

             Describes the mapping of the IP type of service field onto the
             parameters of some specific networks.

             Out of date, needs revision.

          OTHER REFERENCES:

          CONTACT: Postel@USC-ISIF.ARPA

       Address Mappings  ---------------------------------------------------

          STATUS:  None

          SPECIFICATION:  RFC 796 (in IPTW)

          COMMENTS:

             Describes the mapping between Internet Addresses and the
             addresses of some specific networks.

             Out of date, needs revision.

          OTHER REFERENCES:

          CONTACT:  Postel@USC-ISIF.ARPA

       Document Formats  ---------------------------------------------------

          STATUS:  None

          SPECIFICATION:  RFC 678

          COMMENTS:

             Describes standard format rules for several types of documents.

          OTHER REFERENCES:

          CONTACT:  Postel@USC-ISIF.ARPA

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    Official ARPA-Internet Protocols                                 RFC 924

       Bitmap Formats  -----------------------------------------------------

          STATUS:  None

          SPECIFICATION:  RFC 797

          COMMENTS:

             Describes a standard format for bitmap data.

          OTHER REFERENCES:

          CONTACT:  Postel@USC-ISIF.ARPA

       Facsimile Formats  --------------------------------------------------

          STATUS:  None

          SPECIFICATION:  RFC 804

          COMMENTS:

             Describes a standard format for facsimile data.

          OTHER REFERENCES:

          CONTACT:  Postel@USC-ISIF.ARPA

       Internet Protocol on X.25 Networks  ---------------------------------

          STATUS:  Recommended

          SPECIFICATION:  RFC 877

          COMMENTS:

             Describes a standard for the transmission of IP Datagrams over
             Public Data Networks.

          OTHER REFERENCES:

          CONTACT:  jtk@PURDUE.ARPA

    Reynolds & Postel                                              [Page 32]

    Official ARPA-Internet Protocols                                 RFC 924

       Internet Protocol on DC Networks  -----------------------------------

          STATUS:  Elective

          SPECIFICATION: RFC 891

          COMMENTS:

          OTHER REFERENCES:

             RFC 778 - DCNET Internet Clock Service

          CONTACT:  Mills@USC-ISID.ARPA

       Internet Protocol on Ethernet Networks  -----------------------------

          STATUS:  Recommended

          SPECIFICATION: RFC 894

          COMMENTS:

          OTHER REFERENCES:  RFC 893

          CONTACT:  Postel@USC-ISIF.ARPA

       Internet Protocol on Experimental Ethernet Networks  ----------------

          STATUS:  Recommended

          SPECIFICATION: RFC 895

          COMMENTS:

          OTHER REFERENCES:

          CONTACT:  Postel@USC-ISIF.ARPA

    Reynolds & Postel                                              [Page 33]

    Official ARPA-Internet Protocols                                 RFC 924

       Address Resolution Protocol  ---------------------------------- (ARP)

          STATUS:  Recommended

          SPECIFICATION: RFC 826

          COMMENTS:

             This is a procedure for finding the network hardware address
             corresponding to an Internet Address.

          OTHER REFERENCES:

          CONTACT:  Postel@USC-ISIF.ARPA

       A Reverse Address Resolution Protocol  ----------------------- (RARP)

          STATUS:  Elective

          SPECIFICATION: RFC 903

          COMMENTS:

             This is a procedure for workstations to dynamically find their
             protocol address (e.g., their Internet Address), when they only
             only know their hardware address (e.g., their attached physical
             network address).

          OTHER REFERENCES:

          CONTACT:  Mogul@SU-SCORE.ARPA

       Host Access Protocol  ----------------------------------------- (HAP)

          STATUS:  Recommended

          SPECIFICATION:  RFC 907

          COMMENTS:

             This protocol specifies the network-access level communication
             between an arbitrary computer, called a host, and a
             packet-switched satellite network, e.g., SATNET or WBNET.

             Note:  Implementations of HAP should be performed in
             coordination with satellite network development and operations
             personnel.

          OTHER REFERENCES:

    Reynolds & Postel                                              [Page 34]

    Official ARPA-Internet Protocols                                 RFC 924

          DEPENDENCIES:

          CONTACT: Schoen@BBN-UNIX.ARPA

    Reynolds & Postel                                              [Page 35]