[comp.doc] RFC1011 part 1 of 2

brian@sdcsvax.UCSD.EDU (Brian Kantor) (10/12/87)

Network Working Group                                        J. Reynolds
Request for Comments: 1011                                     J. Postel
                                                                     ISI
Obsoletes: RFCs 991, 961, 943, 924, 901, 880, 840               May 1987


                      OFFICIAL INTERNET PROTOCOLS


STATUS OF THIS MEMO

   This memo is an official status report on the protocols used in the
   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.

   The following material 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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      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

            Electronic mail: JKREYNOLDS@ISI.EDU






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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 - A Perspective on the ARPANET Reference Model

      DEPENDENCIES:

      CONTACT: Postel@ISI.EDU














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NETWORK LEVEL

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

      STATUS:  Required

      SPECIFICATION:  RFC 791 (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.

         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.

         The subnet procedures defined in RFC 950 are now considered an
         essential part of the IP architecture and must be implemented
         by all hosts and gateways.

      OTHER REFERENCES:

         RFC 815 (in DPH) - IP Datagram Reassembly Algorithms

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

         RFC 816 (in DPH) - Fault Isolation and Recovery




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

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

         RFC 963 - 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 (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
         "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

      DEPENDENCIES: Internet Protocol

      CONTACT: Postel@ISI.EDU









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

      STATUS:  Recommended

      SPECIFICATION:  RFC 988

      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, and constitutes a proposed protocol standard
         for IP multicasting in the Internet.  Reference RFC 966 for a
         discussion of the motivation and rationale behind the
         multicasting extension specified here.

      OTHER REFERENCES: RFC 966

      DEPENDENCIES: Internet Protocol

      CONTACT: Deering@PESCADERO.STANFORD.EDU




























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HOST LEVEL

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

      STATUS:  Recommended

      SPECIFICATION:  RFC 768 (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 (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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         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.

         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.





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      OTHER REFERENCES:

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

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

         RFC 816 (in DPH) - Fault Isolation and Recovery

         RFC 817 (in DPH) - 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 (in DPH) - Military Standard Transmission Control
         Protocol

         RFC 964 - 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

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

      STATUS:  Experimental

      SPECIFICATION:  RFC 998

      COMMENTS:

         This is a revised RFC on the discussion of the Network Block
         Transfer (NETBLT) protocol.

         NETBLT (NETwork BLock Transfer) is a transport level protocol
         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 designed to provide maximum throughput
         over a wide variety of networks.  Although NETBLT currently


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         runs on top of the Internet Protocol (IP), it should be able to
         operate on top of any datagram protocol similar in function to
         IP.

         This document is published for discussion and comment, and does
         not constitute a standard.  The proposal may change and certain
         parts of the protocol have not yet been specified;
         implementation of this document is therefore not advised.

      OTHER REFERENCES:  RFC 969

      DEPENDENCIES: Transmission Control Protocol, User Datagram
      Protocol

      CONTACT: markl@PTT.LCS.MIT.EDU

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

      STATUS:  Recommended for Gateways

      SPECIFICATION:  RFC 888, RFC 904 (in DPH), RFC 975, RFC 985

      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@UDEL.EDU














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

      STATUS:  Experimental

      SPECIFICATION:  RFC 823 (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

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

      STATUS:  Elective

      SPECIFICATION:  RFC 869 (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











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

      STATUS:  Experimental

      SPECIFICATION:  RFC 908 (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

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

      STATUS:  Experimental

      SPECIFICATION:  RFC 938

      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 Internet 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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   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

      DEPENDENCIES: Internet Protocol

      CONTACT: Postel@ISI.EDU

   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





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   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

      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 (in DPH)

      DEPENDENCIES:  Internet Protocol, Stream Protocol

      CONTACT:  Casner@ISI.EDU




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APPLICATION LEVEL

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

      STATUS:  Recommended

      SPECIFICATION:  RFC 854 (in DPH)

      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 (in DPH) - Telnet Protocol

      DEPENDENCIES:  Transmission Control Protocol

      CONTACT:  Postel@ISI.EDU



























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

      STATUS:  Elective

      SPECIFICATION:  General description of options:  RFC 855 (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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         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

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

      STATUS:  Elective

      SPECIFICATION:  RFC 734 (in DPH)

      COMMENTS:

         A special Telnet like protocol for display terminals.

      OTHER REFERENCES:

      DEPENDENCIES: Transmission Control Protocol

      CONTACT: Crispin@SU-SCORE.STANFORD.EDU

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

      STATUS:  Recommended

      SPECIFICATION:  RFC 959 (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


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         (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).

         A discrepancy has been found in the specification in the
         examples of Appendix II.  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.

      OTHER REFERENCES:

         RFC 678 (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 (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:



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      DEPENDENCIES: User Datagram Protocol

      CONTACT: Postel@ISI.EDU

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

      STATUS:  Experimental

      SPECIFICATION:  RFC 913 (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 (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 (in IPTW) is
         obsolete.



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

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

      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.

            Note:  RFC 822 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

      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 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:



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      DEPENDENCIES: Internet Protocol

      CONTACT: Brian@SDCSVAX.UCSD.EDU

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

      STATUS:  Experimental

      SPECIFICATION:  RFC 937 (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

      DEPENDENCIES: Transmission Control Protocol

      CONTACT: JKReynolds@ISI.EDU

   NetBIOS Services Protocol  -------------------------------- (NETBIOS)

      STATUS:  Recommended

      SPECIFICATION:  RFC 1001, 1002

      COMMENTS:

         These documents define a proposed standard protocol to support
         NetBIOS services in a TCP/IP environment.  Both local network
         and internet operation are supported.  Various node types are
         defined to accomodate local and internet topologies and to
         allow operation with or without the use of IP broadcast

         RFC 1001 describes the NetBIOS-over-TCP protocols in a general
         manner, with emphasis on the underlying ideas and techniques.
         RFC 1002 gives the detailed specifications of the
         NetBIOS-over-TCP packets, protocols, and defined constants and
         variables.



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