RFC 991: Official ARPA-Internet protocols (original) (raw)

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Obsoleted by: 1011 UNKNOWN

Network Working Group J. Reynolds Request for Comments: 991 J. Postel ISI Obsoletes: RFCs 961, 943, 924, 901, 880, 840 November 1986

                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 specified in the "DDN Protocol Handbook" (DPH), dated December 1985 (this is a three volume set with a total thickness of about 5 inches).

Older collections that include many of these specifications are the "Internet Protocol Transition Workbook" (IPTW), dated March 1982; the "Internet Mail Protocols", dated November 1982; and the "Internet Telnet Protocols and Options", dated June 1983. There is also a volume of protocol related information called the "Internet Protocol Implementers Guide" (IPIG) dated August 1982. An even older collection is the "ARPANET Protocol Handbook" (APH) dated January 1978. Nearly all the relevant material from these collections has been reproduced in the current DPH.

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,
  experimental, or none.

  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.

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RFC 991 November 1986 Official ARPA-Internet Protocols

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

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

        Phone: (213) 822-1511

        ARPA mail: JKREYNOLDS@ISI.EDU

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RFC 991 November 1986 Official ARPA-Internet Protocols

OVERVIEW

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

  STATUS:  None

  SPECIFICATION:  IEN 48 (in DPH)

  COMMENTS:

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

     Could be revised and expanded.

  OTHER REFERENCES:

     Leiner, B., Cole R., Postel, J., and D. Mills, "The DARPA
     Protocol Suite", IEEE INFOCOM 85, Washington, D.C., March 1985.
     Also in IEEE Communications Magazine, and as ISI/RS-85-153,
     March 1985.

     Postel, J., "Internetwork Applications Using the DARPA Protocol
     Suite", IEEE INFOCOM 85, Washington, D.C., March 1985. Also in
     IEEE Communications Magazine, and as ISI/RS-85-151, April 1985.

     Padlipsky, M.A., "The Elements of Networking Style and other
     Essays and Animadversions on the Art of Intercomputer
     Networking", Prentice-Hall, New Jersey, 1985.

     [RFC 871](./rfc871) - A Perspective on the ARPANET Reference Model

  DEPENDENCIES:

  CONTACT: Postel@ISI.EDU

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RFC 991 November 1986 Official ARPA-Internet Protocols

NETWORK LEVEL

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

  STATUS:  Required

  SPECIFICATION:  [RFC 791](./rfc791) (in DPH)

  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.  The MIL-STD description of source routing is wrong in
     some of the details.

     Another important point is the alternate reassembly procedure
     suggested in [RFC 815](./rfc815).

     Some changes are in the works for the security option.

     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](./rfc815) (in DPH) - IP Datagram Reassembly Algorithms

     [RFC 814](./rfc814) (in DPH) - Names, Addresses, Ports, and Routes

     [RFC 816](./rfc816) (in DPH) - Fault Isolation and Recovery

     [RFC 817](./rfc817) (in DPH) - Modularity and Efficiency in Protocol
     Implementation

     MIL-STD-1777 (in DPH) - Military Standard Internet Protocol

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RFC 991 November 1986 Official ARPA-Internet Protocols

     [RFC 963](./rfc963) - Some Problems with the Specification of the Military
     Standard Internet Protocol

  DEPENDENCIES:

  CONTACT: Postel@ISI.EDU

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

  STATUS:  Required

  SPECIFICATION:  [RFC 792](./rfc792) (in DPH)

  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.

     Two additional ICMP message types are defined in [RFC 950](./rfc950)
     "Internet Subnets", Address Mask Request (A1=17), and Address
     Mask Reply (A2=18).

     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 950](./rfc950)

  DEPENDENCIES: Internet Protocol

  CONTACT: Postel@ISI.EDU

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RFC 991 November 1986 Official ARPA-Internet Protocols

Internet Group Multicast Protocol --------------------------- (IGMP)

  STATUS:  Recommended

  SPECIFICATION:  [RFC 988](./rfc988)

  COMMENTS:

     This protocol specifies the extensions required of a host
     implementation of the Internet Protocol (IP) to support
     internetwork multicasting.  This specification supersedes that
     given in [RFC 966](./rfc966), and constitutes a proposed protocol standard
     for IP multicasting in the ARPA-Internet.  Reference [RFC 966](./rfc966)
     for a discussion of the motivation and rationale behind the
     multicasting extension specified here.

  OTHER REFERENCES: [RFC 966](./rfc966)

  DEPENDENCIES: Internet Protocol

  CONTACT: Deering@PESCADERO.STANFORD.EDU

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RFC 991 November 1986 Official ARPA-Internet Protocols

HOST LEVEL

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

  STATUS:  Recommended

  SPECIFICATION:  [RFC 768](./rfc768) (in DPH)

  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@ISI.EDU

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

  STATUS:  Recommended

  SPECIFICATION:  [RFC 793](./rfc793) (in DPH)

  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.

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RFC 991 November 1986 Official ARPA-Internet Protocols

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

     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 is 576.  The
     default TCP Maximum Segment Size is 536.  For further
     discussion, see [RFC 879](./rfc879).

     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:

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RFC 991 November 1986 Official ARPA-Internet Protocols

     [RFC 813](./rfc813) (in DPH) - Window and Acknowledgement Strategy in TCP

     [RFC 814](./rfc814) (in DPH) - Names, Addresses, Ports, and Routes

     [RFC 816](./rfc816) (in DPH) - Fault Isolation and Recovery

     [RFC 817](./rfc817) (in DPH) - Modularity and Efficiency in Protocol
     Implementation

     [RFC 879](./rfc879) - TCP Maximum Segment Size

     [RFC 889](./rfc889) - Internet Delay Experiments

     [RFC 896](./rfc896) - TCP/IP Congestion Control

     MIL-STD-1778 (in DPH) - Military Standard Transmission Control
     Protocol

     [RFC 964](./rfc964) - Some Problems with the Specification of the Military
     Standard Transmission Control Protocol

     Zhang, Lixia, "Why TCP Timers Don't Work Well", Communications
     Architectures and Protocols, ACM SIGCOMM Proceedings,  Computer
     Communications Review, V.16, N.3, August 1986.

  DEPENDENCIES: Internet Protocol

  CONTACT: Postel@ISI.EDU

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RFC 991 November 1986 Official ARPA-Internet Protocols

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

  STATUS:  Elective

  SPECIFICATION:  [RFC 869](./rfc869) (in DPH)

  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.COM

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

  STATUS:  Elective

  SPECIFICATION:  IEN 158 (in DPH)

  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](./rfc643)

  DEPENDENCIES: Internet Protocol

  CONTACT: Postel@ISI.EDU

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RFC 991 November 1986 Official ARPA-Internet Protocols

Exterior Gateway Protocol ------------------------------------ (EGP)

  STATUS:  Recommended for Gateways

  SPECIFICATION:  [RFC 888](./rfc888), [RFC 904](./rfc904) (in DPH), [RFC 975](./rfc975)

  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](./rfc827), [RFC 890](./rfc890)

  DEPENDENCIES: Internet Protocol

  CONTACT: Mills@ISI.EDU

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

  STATUS:  Experimental

  SPECIFICATION:  [RFC 823](./rfc823) (in DPH)

  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.COM

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RFC 991 November 1986 Official ARPA-Internet Protocols

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

  STATUS:  Experimental

  SPECIFICATION:  IEN 90 (in DPH)

  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@ISI.EDU

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

  STATUS:  Experimental

  SPECIFICATION:  IEN 119 (in DPH)

  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

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RFC 991 November 1986 Official ARPA-Internet Protocols

  CONTACT: jwf@LL-EN.ARPA

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](./rfc741) (in DPH)

  DEPENDENCIES:  Internet Protocol, Stream Protocol

  CONTACT:  Casner@ISI.EDU

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

  STATUS:  Experimental

  SPECIFICATION:  [RFC 908](./rfc908) (in DPH)

  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.

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

  OTHER REFERENCES:

  DEPENDENCIES:  Internet Protocol

  CONTACT:  CWelles@BBN.COM

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RFC 991 November 1986 Official ARPA-Internet Protocols

Internet Reliable Transaction Protocol ---------------------- (IRTP)

  STATUS:  Experimental

  SPECIFICATION:  [RFC 938](./rfc938)

  COMMENTS:

     This protocol is a transport level host to host protocol
     designed for an internet environment.  While the issues
     discussed may not be directly relevant to the research problems
     of the DARPA community, they may be interesting to a number of
     researchers and implementors.

  OTHER REFERENCES:

  DEPENDENCIES:  Internet Protocol

  CONTACT:  Trudy@ACC.ARPA

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RFC 991 November 1986 Official ARPA-Internet Protocols

APPLICATION LEVEL

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

  STATUS:  Recommended

  SPECIFICATION:  [RFC 854](./rfc854) (in DPH)

  COMMENTS:

     The protocol for remote terminal access.

     This has been revised since the IPTW.  [RFC 764](./rfc764) in IPTW is now
     obsolete.

  OTHER REFERENCES:

     MIL-STD-1782 (in DPH) - Telnet Protocol

  DEPENDENCIES:  Transmission Control Protocol

  CONTACT:  Postel@ISI.EDU

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RFC 991 November 1986 Official ARPA-Internet Protocols

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

  STATUS:  Elective

  SPECIFICATION:  General description of options:  [RFC 855](./rfc855) (in DPH)

  Number   Name                                    RFC  NIC  DPH USE
  ------   ---------------------------------       --- ----- --- ---
     0     Binary Transmission                     856 ----- yes yes
     1     Echo                                    857 ----- yes yes
     2     Reconnection                            ... 15391 yes  no
     3     Suppress Go Ahead                       858 ----- yes yes
     4     Approx Message Size Negotiation         ... 15393 yes  no
     5     Status                                  859 ----- yes yes
     6     Timing Mark                             860 ----- yes yes
     7     Remote Controlled Trans and Echo        726 39237 yes  no
     8     Output Line Width                       ... 20196 yes  no
     9     Output Page Size                        ... 20197 yes  no
    10     Output Carriage-Return Disposition      652 31155 yes  no
    11     Output Horizontal Tabstops              653 31156 yes  no
    12     Output Horizontal Tab Disposition       654 31157 yes  no
    13     Output Formfeed Disposition             655 31158 yes  no
    14     Output Vertical Tabstops                656 31159 yes  no
    15     Output Vertical Tab Disposition         657 31160 yes  no
    16     Output Linefeed Disposition             658 31161 yes  no
    17     Extended ASCII                          698 32964 yes  no
    18     Logout                                  727 40025 yes  no
    19     Byte Macro                              735 42083 yes  no
    20     Data Entry Terminal                     732 41762 yes  no
    21     SUPDUP                              734 736 42213 yes  no
    22     SUPDUP Output                           749 45449 yes  no
    23     Send Location                           779 ----- yes  no
    24     Terminal Type                           930 ----- yes  no
    25     End of Record                           885 ----- yes  no
    26     TACACS User Identification              927 ----- yes  no
    27     Output Marking                          933 ----- yes  no
    28     Terminal Location Number                946 -----  no  no
   255     Extended-Options-List                   861 ----- yes yes

  The DHP column indicates if the specification is included in the
  DDN 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,

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RFC 991 November 1986 Official ARPA-Internet Protocols

     Timing Mark, and Extended Options List options have been
     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@ISI.EDU

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

  STATUS:  Recommended

  SPECIFICATION:  [RFC 959](./rfc959) (in DPH)

  COMMENTS:

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

     The following new optional commands are included in this
     edition of the specification:  Change to Parent Directory
     (CDUP), Structure Mount (SMNT), Store Unique (STOU), Remove
     Directory (RMD), Make Directory (MKD), Print Directory (PWD),
     and System (SYST).  Note that this specification is compatible
     with the previous edition ([RFC 765](./rfc765)).

     A discrepancy has been found in the specification in the
     examples of [Appendix I](#appendix-I)I.  On page 63, a response code of 200 is
     shown as the response to a CWD command.  Under the list of
     Command-Reply Sequences cited on page 50, CWD is shown to only
     accept a 250 response code.  Therefore, if one would interpret
     a CWD command as being excluded from the File System functional
     category, one may assume that the response code of 200 is
     correct, since CDUP as a special case of CWD does use 200.

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RFC 991 November 1986 Official ARPA-Internet Protocols

  OTHER REFERENCES:

     [RFC 678](./rfc678) (in DPH) - Document File Format Standards

     MIL-STD-1780 (in DPH) - File Transfer Protocol

  DEPENDENCIES: Transmission Control Protocol

  CONTACT: Postel@ISI.EDU

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

  STATUS:  Elective

  SPECIFICATION:  [RFC 783](./rfc783) (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.

     Note: The DPH contains IEN-133, which is an obsolete version of
     this protocol.

  OTHER REFERENCES:

  DEPENDENCIES: User Datagram Protocol

  CONTACT: Postel@ISI.EDU

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RFC 991 November 1986 Official ARPA-Internet Protocols

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

  STATUS:  Experimental

  SPECIFICATION:  [RFC 913](./rfc913) (in DPH)

  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@SRI-NIC.ARPA

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

  STATUS:  Recommended

  SPECIFICATION:  [RFC 821](./rfc821) (in DPH)

  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](./rfc788) (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 [ISIB]<SMTP>MAIL.ERRORS.

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RFC 991 November 1986 Official ARPA-Internet Protocols

     Some minor differences between [RFC 821](./rfc821) and [RFC 822](./rfc822) should be
     resolved.

  OTHER REFERENCES:

     [RFC 822](./rfc822) - Mail Header Format Standards

        This has been revised since the IPTW, it is in the "Internet
        Mail Protocols" volume of November 1982.  [RFC 733](./rfc733) (in IPTW)
        is obsolete.  Further revision of [RFC 822](./rfc822) is needed to
        correct some minor errors in the details of the
        specification.

        Note:  [RFC 822](./rfc822) is not included in the DPH (an accident, it
        should have been).

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

  DEPENDENCIES: Transmission Control Protocol

  CONTACT: Postel@ISI.EDU

Network News Transfer Protocol ------------------------------ (NNTP)

  STATUS:  Experimental

  SPECIFICATION:  [RFC 977](./rfc977)

  COMMENTS:

     NNTP specifies a protocol for the distribution, inquiry,
     retrieval, and posting of news articles using a reliable
     stream-based transmission of news among the ARPA-Internet
     community.  NNTP is designed so that news articles are stored
     in a central database allowing a subscriber to select only
     those items he wishes to read.  Indexing, cross-referencing,
     and expiration of aged messages are also provided.

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

  OTHER REFERENCES:

  DEPENDENCIES: Internet Protocol

  CONTACT: Brian@SDCSVAX.UCSD.EDU

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RFC 991 November 1986 Official ARPA-Internet Protocols

Bulk Data Transfer Protocol ------------------------------- (NETBLT)

  STATUS:  Experimental

  SPECIFICATION:  [RFC 969](./rfc969)

  COMMENTS:

     This is a preliminary discussion of the Network Block Transfer
     (NETBLT) protocol.  NETBLT is intended for the rapid transfer
     of a large quantity of data between computers.  It provides a
     transfer that is reliable and flow controlled, and is
     structured to provide maximum throughput over a wide variety of
     networks.

     Note: A new RFC on the revised NETBLT is coming soon.

  OTHER REFERENCES:

  DEPENDENCIES: Transmission Control Protocol, User Datagram
  Protocol

  CONTACT: DClark@MIT-MULTICS.ARPA

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

  STATUS:   Elective

  SPECIFICATION:   [RFC 887](./rfc887) (in DPH)

  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@A.CS.CMU.EDU

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RFC 991 November 1986 Official ARPA-Internet Protocols

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

  STATUS:  Experimental

  SPECIFICATION:  [RFC 909](./rfc909)

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

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

  OTHER REFERENCES:

  DEPENDENCIES:  Reliable Data Protocol

  CONTACT:  Hinden@BBN.COM

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

  STATUS:  Elective

  SPECIFICATION:  [RFC 407](./rfc407) (in DPH)

  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@ISI.EDU

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RFC 991 November 1986 Official ARPA-Internet Protocols

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

  STATUS:  Elective

  SPECIFICATION:  [RFC 740](./rfc740) (in DPH)

  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:

  DEPENDENCIES: Transmission Control Protocol

  CONTACT: Braden@ISI.EDU

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

  STATUS:  Elective

  SPECIFICATION:  [RFC 818](./rfc818) (in DPH)

  COMMENTS:

     Provides special access to user Telnet on a remote system.

  OTHER REFERENCES:

  DEPENDENCIES: Telnet, Transmission Control Protocol

  CONTACT: Postel@ISI.EDU

Reynolds & Postel [Page 23]


RFC 991 November 1986 Official ARPA-Internet Protocols

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

  STATUS:  Elective

  SPECIFICATION:  NIC 24308 (in DPH)

  COMMENTS:

     The protocol for vector graphics.

     Very minor changes needed for use with TCP.

     No known active implementations.

     Note:  The DPH claims that this is [RFC 493](./rfc493), but [RFC 493](./rfc493) is
     actually a different earlier specification.

  OTHER REFERENCES:

  DEPENDENCIES: Telnet, Transmission Control Protocol

  CONTACT: Postel@ISI.EDU

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

  STATUS:  Recommended

  SPECIFICATION:  [RFC 862](./rfc862) (in DPH)

  COMMENTS:

     Debugging protocol, sends back whatever you send it.

  OTHER REFERENCES:

  DEPENDENCIES: Transmission Control Protocol
                or User Datagram Protocol

  CONTACT: Postel@ISI.EDU

Reynolds & Postel [Page 24]


RFC 991 November 1986 Official ARPA-Internet Protocols

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

  STATUS:  Elective

  SPECIFICATION:  [RFC 863](./rfc863) (in DPH)

  COMMENTS:

     Debugging protocol, throws away whatever you send it.

  OTHER REFERENCES:

  DEPENDENCIES: Transmission Control Protocol
                or User Datagram Protocol

  CONTACT: Postel@ISI.EDU

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

  STATUS:  Elective

  SPECIFICATION:  [RFC 864](./rfc864) (in DPH)

  COMMENTS:

     Debugging protocol, sends you ASCII data.

  OTHER REFERENCES:

  DEPENDENCIES: Transmission Control Protocol
                or User Datagram Protocol

  CONTACT: Postel@ISI.EDU

Reynolds & Postel [Page 25]


RFC 991 November 1986 Official ARPA-Internet Protocols

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

  STATUS:  Elective

  SPECIFICATION:  [RFC 865](./rfc865) (in DPH)

  COMMENTS:

     Debugging protocol, sends you a short ASCII message.

  OTHER REFERENCES:

  DEPENDENCIES: Transmission Control Protocol
                or User Datagram Protocol

  CONTACT: Postel@ISI.EDU

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

  STATUS:  Elective

  SPECIFICATION:  [RFC 866](./rfc866) (in DPH)

  COMMENTS:

     Lists the currently active users.

  OTHER REFERENCES:

  DEPENDENCIES: Transmission Control Protocol
                or User Datagram Protocol

  CONTACT: Postel@ISI.EDU

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

  STATUS:  Elective

  SPECIFICATION:  [RFC 742](./rfc742) (in DPH)

  COMMENTS:

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

     Some extensions have been suggested.

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RFC 991 November 1986 Official ARPA-Internet Protocols

     Some changes are are needed for TCP.

  OTHER REFERENCES:

  DEPENDENCIES: Transmission Control Protocol

  CONTACT: Postel@ISI.EDU

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

  STATUS:  Elective

  SPECIFICATION:  [RFC 954](./rfc954) (in DPH)

  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

  CONTACT: Feinler@SRI-NIC.ARPA

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

  STATUS:  Recommended

  SPECIFICATION:  [RFC 881](./rfc881), [RFC 882](./rfc882), [RFC 883](./rfc883) (in DPH)

  COMMENTS:

  OTHER REFERENCES:

     [RFC 920](./rfc920) - Domain Requirements

     [RFC 921](./rfc921) - Domain Name Implementation Schedule - Revised

     [RFC 973](./rfc973) - Domain System Changes and Observations

     [RFC 974](./rfc974) - Mail Routing and the Domain System

  DEPENDENCIES: Transmission Control Protocol
                or User Datagram Protocol

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RFC 991 November 1986 Official ARPA-Internet Protocols

  CONTACT: Mockapetris@ISI.EDU

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

  STATUS:  Elective

  SPECIFICATION:  [RFC 953](./rfc953) (in DPH)

  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 952](./rfc952) - Host Table Specification

  DEPENDENCIES: Transmission Control Protocol

  CONTACT: Feinler@SRI-NIC.ARPA

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

  STATUS:  Experimental

  SPECIFICATION:  IEN 116 (in DPH)

  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 abandoned 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:

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RFC 991 November 1986 Official ARPA-Internet Protocols

  DEPENDENCIES: User Datagram Protocol

  CONTACT: Postel@ISI.EDU

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

  STATUS:  Experimental

  SPECIFICATION:  CS-DN-2 (in DPH)

  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@WISC.EDU

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

  STATUS:  Elective

  SPECIFICATION:  [RFC 867](./rfc867) (in DPH)

  COMMENTS:

     Provides the day and time in ASCII character string.

  OTHER REFERENCES:

  DEPENDENCIES: Transmission Control Protocol
                or User Datagram Protocol

  CONTACT: Postel@ISI.EDU

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RFC 991 November 1986 Official ARPA-Internet Protocols

Network Time Protocol ---------------------------------------- (NTP)

  STATUS:  Experimental

  SPECIFICATION:  [RFC 958](./rfc958)

  COMMENTS:

     A proposed protocol for synchronizing a set of network clocks
     using a set of distributed clients and servers.

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

  OTHER REFERENCES:  [RFC 778](./rfc778), [RFC 891](./rfc891), [RFC 956](./rfc956), and [RFC 957](./rfc957).

  DEPENDENCIES: User Datagram Protocol

  CONTACT: Mills@ISI.EDU

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

  STATUS:  Elective

  SPECIFICATION:  [RFC 868](./rfc868) (in DPH)

  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@ISI.EDU

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RFC 991 November 1986 Official ARPA-Internet Protocols

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

  STATUS:  Experimental

  SPECIFICATION:  [RFC 778](./rfc778)

  COMMENTS:

     Provides a mechanism for keeping synchronized clocks.

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

  OTHER REFERENCES:

  DEPENDENCIES: Internet Control Message Protocol

  CONTACT: Mills@ISI.EDU

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

  STATUS:  Elective

  SPECIFICATION:  [RFC 734](./rfc734) (in DPH)

  COMMENTS:

     A special Telnet like protocol for display terminals.

  OTHER REFERENCES:

  DEPENDENCIES: Transmission Control Protocol

  CONTACT: Crispin@SU-SCORE.STANFORD.EDU

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RFC 991 November 1986 Official ARPA-Internet Protocols

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

  STATUS:  Experimental

  SPECIFICATION:  [RFC 759](./rfc759) (in DPH)

  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](./rfc767) - Structured Document Formats

  DEPENDENCIES: Transmission Control Protocol

  CONTACT: Postel@ISI.EDU

Post Office Protocol - Version 2 ---------------------------- (POP2)

  STATUS:  Experimental

  SPECIFICATION:  [RFC 937](./rfc937) (in DPH)

  COMMENTS:

     The intent of the Post Office Protocol - Version 2 (POP2) 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).

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

  OTHER REFERENCES:  Obsoletes [RFC 918](./rfc918)

  DEPENDENCIES: Transmission Control Protocol

  CONTACT: JKReynolds@ISI.EDU

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RFC 991 November 1986 Official ARPA-Internet Protocols

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

  STATUS:  Elective

  SPECIFICATION:  [RFC 569](./rfc569) (in DPH)

  COMMENTS:

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

  OTHER REFERENCES:

  DEPENDENCIES:

  CONTACT:  Postel@ISI.EDU

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

  STATUS:  Experimental

  SPECIFICATION:  [RFC 931](./rfc931)

  COMMENTS:

     This 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.

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

  OTHER REFERENCES:  Supercedes [RFC 912](./rfc912)

  DEPENDENCIES: Transmission Control Protocol

  CONTACT: StJohns@SRI-NIC.ARPA

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RFC 991 November 1986 Official ARPA-Internet Protocols

Bootstrap Protocol ----------------------------------------- (BOOTP)

  STATUS:  Experimental

  SPECIFICATION:  [RFC 951](./rfc951)

  COMMENTS:

     This proposed protocol provides an IP/UDP bootstrap protocol
     which allows a diskless client machine to discover its own IP
     address, the address of a server host, and the name of a file
     to be loaded into memory and executed.

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

  OTHER REFERENCES:

  DEPENDENCIES: Internet Protocol, User Datagram Protocol

  CONTACT: Croft@SUMEX-AIM.STANFORD.EDU

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RFC 991 November 1986 Official ARPA-Internet Protocols

APPENDICES

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

  STATUS:  None

  SPECIFICATION:  [RFC 990](./rfc990)

  COMMENTS:

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

     Issued November 1986, replaces [RFC 960](./rfc960), [RFC 790](./rfc790) in IPTW, and
     [RFC 943](./rfc943).

  OTHER REFERENCES:

  CONTACT: JKReynolds@ISI.EDU

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

  STATUS:  Elective

  SPECIFICATION:  [RFC 794](./rfc794) (in DPH)

  COMMENTS:

     Describes how to do pre-emption of TCP connections.

  OTHER REFERENCES:

  CONTACT: Postel@ISI.EDU

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RFC 991 November 1986 Official ARPA-Internet Protocols

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

  STATUS:  None

  SPECIFICATION:  [RFC 795](./rfc795) (in DPH)

  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@ISI.EDU

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

  STATUS:  None

  SPECIFICATION:  [RFC 796](./rfc796) (in DPH)

  COMMENTS:

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

     Out of date, needs revision.

  OTHER REFERENCES:

  CONTACT:  Postel@ISI.EDU

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

  STATUS:  None

  SPECIFICATION:  [RFC 678](./rfc678) (in DPH)

  COMMENTS:

     Describes standard format rules for several types of documents.

  OTHER REFERENCES:

  CONTACT:  Postel@ISI.EDU

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RFC 991 November 1986 Official ARPA-Internet Protocols

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

  STATUS:  None

  SPECIFICATION:  [RFC 797](./rfc797) (in DPH)

  COMMENTS:

     Describes a standard format for bitmap data.

  OTHER REFERENCES:

  CONTACT:  Postel@ISI.EDU

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

  STATUS:  None

  SPECIFICATION:  [RFC 804](./rfc804)

  COMMENTS:

     Describes a standard format for facsimile data.

  OTHER REFERENCES:  [RFC 769](./rfc769) (in DPH)

  CONTACT:  Postel@ISI.EDU

Host-Front End Protocol ------------------------------------- (HFEP)

  STATUS:  Experimental

  SPECIFICATION:  [RFC 929](./rfc929)

  COMMENTS:

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

  OTHER REFERENCES:  [RFC 928](./rfc928)

  DEPENDENCIES:

  CONTACT: Padlipsky@ISI.EDU

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RFC 991 November 1986 Official ARPA-Internet Protocols

Internet Protocol on ARPANET ----------------------------- (IP-ARPA)

  STATUS:  Recommended

  SPECIFICATION:  BBN Report 1822

  COMMENTS:

     Describes a standard for the transmission of IP Datagrams over
     the ARPANET.

  OTHER REFERENCES: [RFC 851](./rfc851), [RFC 852](./rfc852), [RFC 878](./rfc878) (in DPH), [RFC 979](./rfc979)

  CONTACT:  Malis@BBN.COM

Internet Protocol on WBNET --------------------------------- (IP-WB)

  STATUS:  Recommended

  SPECIFICATION:  [RFC 907](./rfc907) (in DPH)

  COMMENTS:

     Describes a standard for the transmission of IP Datagrams over
     the Wideband Net.

     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:

  CONTACT:  Blumenthal@BBN.COM

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RFC 991 November 1986 Official ARPA-Internet Protocols

Host Access Protocol -------------------------------------- (IP-SAT)

  STATUS:  Recommended

  SPECIFICATION:  [RFC 907](./rfc907)  (in DPH)

  COMMENTS:

     Describes a standard for the transmission of IP Datagrams over
     the SATNET.

     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:

  DEPENDENCIES:

  CONTACT: Schoen@BBN.COM

Internet Protocol on X.25 Networks ------------------------ (IP-X25)

  STATUS:  Recommended

  SPECIFICATION:  [RFC 877](./rfc877) (in DPH)

  COMMENTS:

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

  OTHER REFERENCES:

  CONTACT:  jtk@PURDUE.EDU

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RFC 991 November 1986 Official ARPA-Internet Protocols

Internet Protocol on DC Networks --------------------------- (IP-DC)

  STATUS:  Elective

  SPECIFICATION: [RFC 891](./rfc891) (in DPH)

  COMMENTS:

  OTHER REFERENCES:

     [RFC 778](./rfc778) - DCNET Internet Clock Service

  CONTACT:  Mills@ISI.EDU

Internet Protocol on Ethernet Networks ---------------------- (IP-E)

  STATUS:  Recommended

  SPECIFICATION: [RFC 894](./rfc894) (in DPH)

  COMMENTS:

  OTHER REFERENCES:  [RFC 893](./rfc893)

  CONTACT:  Postel@ISI.EDU

Internet Protocol on Experimental Ethernet Networks -------- (IP-EE)

  STATUS:  Recommended

  SPECIFICATION: [RFC 895](./rfc895) (in DPH)

  COMMENTS:

  OTHER REFERENCES:

  CONTACT:  Postel@ISI.EDU

Reynolds & Postel [Page 40]


RFC 991 November 1986 Official ARPA-Internet Protocols

Internet Protocol on IEEE 802 ---------------------------- (IP-IEEE)

  STATUS:  Recommended

  SPECIFICATION: [RFC 948](./rfc948) (in DPH)

  COMMENTS:

     A proposed protocol of two methods of encapsulating Internet
     Protocol (IP) datagrams on an IEEE 802.3 network.  Currently
     being revised to be generalized for all 802 networks.

     At an ad hoc special session on "IEEE 802 Networks and ARP"
     held during the TCP Vendors Workshop (August 1986), an approach
     to a consistent way to sent DOD-IP datagrams and other IP
     related protocols on 802 networks was developed.

     Due to some evolution of the IEEE 802.2 standards and the need
     to provide for a standard way to do additional DOD-IP related
     protocols (such as Address Resolution Protocol (ARP)) on IEEE
     802 networks, the following new policy is established, which
     will replace the current policy (see [RFC-990](./rfc990) section on IEEE
     802 Numbers of Interest, and [RFC-948](./rfc948)).

     The policy is for DDN and ARPA-Internet community to use IEEE
     802.2 encapsulation on 802.3, 802.4, and 802.5 networks by
     using the SNAP with an organization code indicating that the
     following 16 bits specify the Ethertype code (where IP = 2048
     (0800 hex), see [RFC-990](./rfc990)  section on Ethernet Numbers of
     Interest).

                                                              Header

        ...--------+--------+--------+
         MAC Header|      Length     |               802.{3/4/5} MAC
        ...--------+--------+--------+

        +--------+--------+--------+
        | Dsap=K1| Ssap=K1| control|                       802.2 SAP
        +--------+--------+--------+

        +--------+--------+---------+--------+--------+
        |protocol id or org code =K2|    Ether Type   |   802.2 SNAP
        +--------+--------+---------+--------+--------+

     The values of K1 and K2 must be assigned by the IEEE.  There is
     already assigned a value of K1 that indicates that the 5-octet

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RFC 991 November 1986 Official ARPA-Internet Protocols

     SNAP header follows.  We can use this value.  There may be a
     value of K2 that is already assigned that indicates that the
     last two octets of the SNAP header holds the EtherType.  If so
     we may be able to use this value.

     The total length of the SAP Header and the SNAP header is
     8-octets, making the 802.2 protocol overhead come out on a nice
     octet boundary.

     K1 is 170.  The IEEE like to talk about things in bit
     transmission order and specifies this value as 01010101.  In
     big-endian order, as used in Internet specifications, this
     becomes 10101010 binary, or AA hex, or 170 decimal.

     We believe that K2 is 0 (zero).  This must be further
     investigated, but as an interim measure use K2 = 0.

  OTHER REFERENCES:

  CONTACT:  Postel@ISI.EDU

Internet Subnet Protocol ---------------------------------- (IP-SUB)

  STATUS:  Recommended

  SPECIFICATION: [RFC 950](./rfc950)

  COMMENTS:

     This is a very important feature and should be included in all
     IP implementations.

     Specifies procedures for the use of subnets, which are logical
     sub-sections of a single Internet network.

  OTHER REFERENCES:  [RFC 940](./rfc940), [RFC 917](./rfc917), [RFC 925](./rfc925), [RFC 932](./rfc932), [RFC 936](./rfc936),
  [RFC 922](./rfc922)

  DEPENDENCIES:

  CONTACT:  Mogul@SU-SCORE.STANFORD.EDU

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RFC 991 November 1986 Official ARPA-Internet Protocols

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

  STATUS:  Recommended

  SPECIFICATION: [RFC 826](./rfc826)  (IN DPH)

  COMMENTS:

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

  OTHER REFERENCES:

  CONTACT:  Postel@ISI.EDU

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

  STATUS:  Elective

  SPECIFICATION: [RFC 903](./rfc903) (IN DPH)

  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.STANFORD.EDU

Multi-LAN Address Resolution Protocol ----------------------- (MARP)

  STATUS:  Experimental

  SPECIFICATION: [RFC 925](./rfc925)

  COMMENTS:

     Discussion of the various problems and potential solutions of
     "transparent subnets" in a multi-LAN environment.

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

  OTHER REFERENCES:  [RFC 917](./rfc917), [RFC 826](./rfc826)

Reynolds & Postel [Page 43]


RFC 991 November 1986 Official ARPA-Internet Protocols

  DEPENDENCIES:

  CONTACT:  Postel@ISI.EDU

Broadcasting Internet Datagrams ------------------------- (IP-BROAD)

  STATUS:  Recommended

  SPECIFICATION:  [RFC 919](./rfc919)

  COMMENTS:

     A proposed protocol of simple rules for broadcasting Internet
     datagrams on local networks that support broadcast, for
     addressing broadcasts, and for how gateways should handle them.

     Recommended in the sense of "if you do broadcasting at all then
     do it this way".

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

  OTHER REFERENCES:  [RFC 922](./rfc922)

  DEPENDENCIES:

  CONTACT: Mogul@SU-SCORE.STANFORD.EDU

Broadcasting Internet Datagrams with Subnets --------- (IP-SUB-BROAD)

  STATUS:  Recommended

  SPECIFICATION:  [RFC 922](./rfc922)

  COMMENTS:

     A proposed protocol of simple rules for broadcasting Internet
     datagrams on local networks that support broadcast, for
     addressing broadcasts, and for how gateways should handle them.

     Recommended in the sense of "if you do broadcasting with
     subnets at all then do it this way".

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

  OTHER REFERENCES: [RFC 919](./rfc919)

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RFC 991 November 1986 Official ARPA-Internet Protocols

  DEPENDENCIES:

  CONTACT: Mogul@SU-SCORE.STANFORD.EDU

Reliable Asynchronous Transfer Protocol --------------------- (RATP)

  STATUS:  Experimental

  SPECIFICATION:  [RFC 916](./rfc916)

  COMMENTS:

     This paper specifies a protocol which allows two programs to
     reliably communicate over a communication link.  It ensures
     that the data entering one end of the link if received arrives
     at the other end intact and unaltered.  This proposed protocol
     is designed to operate over a full duplex point-to-point
     connection.  It contains some features which tailor it to the
     RS-232 links now in current use.

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

  OTHER REFERENCES:

  DEPENDENCIES: Transmission Control Protocol

  CONTACT: Finn@ISI.EDU

Thinwire Protocol --------------------------------------- (THINWIRE)

  STATUS:  Experimental

  SPECIFICATION:  [RFC 914](./rfc914)

  COMMENTS:

     This paper discusses a Thinwire Protocol for connecting
     personal computers to the ARPA-Internet.  It primarily focuses
     on the particular problems in the ARPA-Internet of low speed
     network interconnection with personal computers, and possible
     methods of solution.

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

  OTHER REFERENCES:

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RFC 991 November 1986 Official ARPA-Internet Protocols

  DEPENDENCIES:

  CONTACT: Farber@HUEY.UDEL.EDU

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