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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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 - A Perspective on the ARPANET Reference Model
DEPENDENCIES:
CONTACT: Postel@ISI.EDU
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Official ARPA-Internet Protocols
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.
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
RFC 817 (in DPH) - Modularity and Efficiency in Protocol
Implementation
MIL-STD-1777 (in DPH) - Military Standard Internet Protocol
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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 ARPA-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.
OTHER REFERENCES:
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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
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Official ARPA-Internet Protocols
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
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
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Exterior Gateway Protocol ------------------------------------ (EGP)
STATUS: Recommended for Gateways
SPECIFICATION: RFC 888, RFC 904 (in DPH), RFC 975
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@ISI.EDU
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
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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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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
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
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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 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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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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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 (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).
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.
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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:
DEPENDENCIES: User Datagram Protocol
CONTACT: Postel@ISI.EDU
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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.
There have been many misunderstandings and errors in the early
implementations. Some documentation of these problems can be
found in the file [ISIB]MAIL.ERRORS.
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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 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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Bulk Data Transfer Protocol ------------------------------- (NETBLT)
STATUS: Experimental
SPECIFICATION: RFC 969
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 (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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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
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 (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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Remote Job Service ---------------------------------------- (NETRJS)
STATUS: Elective
SPECIFICATION: RFC 740 (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 (in DPH)
COMMENTS:
Provides special access to user Telnet on a remote system.
OTHER REFERENCES:
DEPENDENCIES: Telnet, Transmission Control Protocol
CONTACT: Postel@ISI.EDU
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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, but RFC 493 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 (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
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Discard Protocol ----------------------------------------- (DISCARD)
STATUS: Elective
SPECIFICATION: RFC 863 (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 (in DPH)
COMMENTS:
Debugging protocol, sends you ASCII data.
OTHER REFERENCES:
DEPENDENCIES: Transmission Control Protocol
or User Datagram Protocol
CONTACT: Postel@ISI.EDU
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Quote of the Day Protocol ---------------------------------- (QUOTE)
STATUS: Elective
SPECIFICATION: RFC 865 (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 (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 (in DPH)
COMMENTS:
Provides information on the current or most recent activity of
a user.
Some extensions have been suggested.
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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 (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, RFC 882, RFC 883 (in DPH)
COMMENTS:
OTHER REFERENCES:
RFC 920 - Domain Requirements
RFC 921 - Domain Name Implementation Schedule - Revised
RFC 973 - Domain System Changes and Observations
RFC 974 - Mail Routing and the Domain System
DEPENDENCIES: Transmission Control Protocol
or User Datagram Protocol
Reynolds & Postel [Page 27]
RFC 991 November 1986
Official ARPA-Internet Protocols
CONTACT: Mockapetris@ISI.EDU
HOSTNAME Protocol --------------------------------------- (HOSTNAME)
STATUS: Elective
SPECIFICATION: RFC 953 (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 - 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:
Reynolds & Postel [Page 28]
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 (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
Reynolds & Postel [Page 29]
RFC 991 November 1986
Official ARPA-Internet Protocols
Network Time Protocol ---------------------------------------- (NTP)
STATUS: Experimental
SPECIFICATION: RFC 958
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, RFC 891, RFC 956, and RFC 957.
DEPENDENCIES: User Datagram Protocol
CONTACT: Mills@ISI.EDU
Time Server Protocol ---------------------------------------- (TIME)
STATUS: Elective
SPECIFICATION: RFC 868 (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
Reynolds & Postel [Page 30]
RFC 991 November 1986
Official ARPA-Internet Protocols
DCNET Time Server Protocol --------------------------------- (CLOCK)
STATUS: Experimental
SPECIFICATION: RFC 778
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 (in DPH)
COMMENTS:
A special Telnet like protocol for display terminals.
OTHER REFERENCES:
DEPENDENCIES: Transmission Control Protocol
CONTACT: Crispin@SU-SCORE.STANFORD.EDU
Reynolds & Postel [Page 31]
RFC 991 November 1986
Official ARPA-Internet Protocols
Internet Message Protocol ------------------------------------ (MPM)
STATUS: Experimental
SPECIFICATION: RFC 759 (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 - Structured Document Formats
DEPENDENCIES: Transmission Control Protocol
CONTACT: Postel@ISI.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
Reynolds & Postel [Page 32]
RFC 991 November 1986
Official ARPA-Internet Protocols
Network Standard Text Editor ------------------------------- (NETED)
STATUS: Elective
SPECIFICATION: RFC 569 (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
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
DEPENDENCIES: Transmission Control Protocol
CONTACT: StJohns@SRI-NIC.ARPA
Reynolds & Postel [Page 33]
RFC 991 November 1986
Official ARPA-Internet Protocols
Bootstrap Protocol ----------------------------------------- (BOOTP)
STATUS: Experimental
SPECIFICATION: RFC 951
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
Reynolds & Postel [Page 34]
RFC 991 November 1986
Official ARPA-Internet Protocols
APPENDICES
Assigned Numbers ---------------------------------------------------
STATUS: None
SPECIFICATION: RFC 990
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, RFC 790 in IPTW, and
RFC 943.
OTHER REFERENCES:
CONTACT: JKReynolds@ISI.EDU
Pre-emption --------------------------------------------------------
STATUS: Elective
SPECIFICATION: RFC 794 (in DPH)
COMMENTS:
Describes how to do pre-emption of TCP connections.
OTHER REFERENCES:
CONTACT: Postel@ISI.EDU
Reynolds & Postel [Page 35]
RFC 991 November 1986
Official ARPA-Internet Protocols
Service Mappings ---------------------------------------------------
STATUS: None
SPECIFICATION: RFC 795 (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 (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 (in DPH)
COMMENTS:
Describes standard format rules for several types of documents.
OTHER REFERENCES:
CONTACT: Postel@ISI.EDU
Reynolds & Postel [Page 36]
RFC 991 November 1986
Official ARPA-Internet Protocols
Bitmap Formats -----------------------------------------------------
STATUS: None
SPECIFICATION: RFC 797 (in DPH)
COMMENTS:
Describes a standard format for bitmap data.
OTHER REFERENCES:
CONTACT: Postel@ISI.EDU
Facsimile Formats --------------------------------------------------
STATUS: None
SPECIFICATION: RFC 804
COMMENTS:
Describes a standard format for facsimile data.
OTHER REFERENCES: RFC 769 (in DPH)
CONTACT: Postel@ISI.EDU
Host-Front End Protocol ------------------------------------- (HFEP)
STATUS: Experimental
SPECIFICATION: RFC 929
COMMENTS:
Please discuss any plans for implementation or use of this
protocol with the contact.
OTHER REFERENCES: RFC 928
DEPENDENCIES:
CONTACT: Padlipsky@ISI.EDU
Reynolds & Postel [Page 37]
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, RFC 852, RFC 878 (in DPH), RFC 979
CONTACT: Malis@BBN.COM
Internet Protocol on WBNET --------------------------------- (IP-WB)
STATUS: Recommended
SPECIFICATION: RFC 907 (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
Reynolds & Postel [Page 38]
RFC 991 November 1986
Official ARPA-Internet Protocols
Host Access Protocol -------------------------------------- (IP-SAT)
STATUS: Recommended
SPECIFICATION: RFC 907 (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 (in DPH)
COMMENTS:
Describes a standard for the transmission of IP Datagrams over
Public Data Networks.
OTHER REFERENCES:
CONTACT: jtk@PURDUE.EDU
Reynolds & Postel [Page 39]
RFC 991 November 1986
Official ARPA-Internet Protocols
Internet Protocol on DC Networks --------------------------- (IP-DC)
STATUS: Elective
SPECIFICATION: RFC 891 (in DPH)
COMMENTS:
OTHER REFERENCES:
RFC 778 - DCNET Internet Clock Service
CONTACT: Mills@ISI.EDU
Internet Protocol on Ethernet Networks ---------------------- (IP-E)
STATUS: Recommended
SPECIFICATION: RFC 894 (in DPH)
COMMENTS:
OTHER REFERENCES: RFC 893
CONTACT: Postel@ISI.EDU
Internet Protocol on Experimental Ethernet Networks -------- (IP-EE)
STATUS: Recommended
SPECIFICATION: RFC 895 (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 (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 section on IEEE
802 Numbers of Interest, and RFC-948).
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 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
Reynolds & Postel [Page 41]
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
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, RFC 917, RFC 925, RFC 932, RFC 936,
RFC 922
DEPENDENCIES:
CONTACT: Mogul@SU-SCORE.STANFORD.EDU
Reynolds & Postel [Page 42]
RFC 991 November 1986
Official ARPA-Internet Protocols
Address Resolution Protocol ---------------------------------- (ARP)
STATUS: Recommended
SPECIFICATION: RFC 826 (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 (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
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, RFC 826
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
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
DEPENDENCIES:
CONTACT: Mogul@SU-SCORE.STANFORD.EDU
Broadcasting Internet Datagrams with Subnets --------- (IP-SUB-BROAD)
STATUS: Recommended
SPECIFICATION: RFC 922
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
Reynolds & Postel [Page 44]
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
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
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:
Reynolds & Postel [Page 45]
RFC 991 November 1986
Official ARPA-Internet Protocols
DEPENDENCIES:
CONTACT: Farber@HUEY.UDEL.EDU
Reynolds & Postel [Page 46]
RFC, FYI, BCP