RFC880 - Official protocols

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　　Network Working Group J. Reynolds
Request for Comments: 880 J. Postel
ISI
Obsoletes: RFC840 October 1983

OFFICIAL PROTOCOLS

This RFCidentifies the documents specifying the official protocols used

in the Internet. Annotations identify any revisions or changes planned.

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

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

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

The specification identifies the protocol defining documents.

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

The other references identify documents that comment on or expand on
the protocol.

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

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

Official Protocols RFC880

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.

Overview

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

STATUS: None

SPECIFICATION: IEN 48 (in IPTW)

COMMENTS:

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

Could be revised and expanded.

OTHER REFERENCES:

RFC871 - A Perspective on the ARPANET Reference Model

DEPENDENCIES:

CONTACT: Postel@USC-ISIF

Official Protocols RFC880

Network Level

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

STATUS: Required

SPECIFICATION: RFC791 (in IPTW)

COMMENTS:

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

A few minor problems have been noted in this document.

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

Another important point is the alternate reassembly procedure
suggested in RFC815.

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:

RFC815 (in IPIG) - IP Datagram Reassembly Algorithms

RFC814 (in IPIG) - Names, Addresses, Ports, and Routes

RFC816 (in IPIG) - Fault Isolation and Recovery

RFC817 (in IPIG) - Modularity and Efficiency in Protocol
Implementation

DEPENDENCIES:

CONTACT: Postel@USC-ISIF

Official Protocols RFC880

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

STATUS: Required

SPECIFICATION: RFC792 (in IPTW)

COMMENTS:

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

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

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:

DEPENDENCIES: Internet Protocol

CONTACT: Postel@USC-ISIF

Host Level

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

STATUS: Recommended

SPECIFICATION: RFC768 (in IPTW)

COMMENTS:

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

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

OTHER REFERENCES:

DEPENDENCIES: Internet Protocol

CONTACT: Postel@USC-ISIF

Official Protocols RFC880

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

STATUS: Recommended

SPECIFICATION: RFC793 (in IPTW)

COMMENTS:

Provides reliable end-to-end data stream service.

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

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

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

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 default should be established more clearly. The default is
based on the default maximum Internet Datagram size which is
576 octets counting the IP and TCP headers. The option counts
only the segment data. For each of IP and TCP the minimum
header is 20 octets and the maximum header is 60 octets. So the
default maximum data segment is could be anywhere from 456 to
536 octets. The current proposal is to set it at 536 data
octets.

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

Official Protocols RFC880

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:

RFC813 (in IPIG) - Window and Acknowledgement Strategy in TCP

RFC814 (in IPIG) - Names, Addresses, Ports, and Routes

RFC816 (in IPIG) - Fault Isolation and Recovery

RFC817 (in IPIG) - Modularity and Efficiency in Protocol
Implementation

DEPENDENCIES: Internet Protocol

CONTACT: Postel@USC-ISIF

Official Protocols RFC880

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

STATUS: Elective

SPECIFICATION: IEN 197

COMMENTS:

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

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

OTHER REFERENCES:

DEPENDENCIES: Internet Protocol

CONTACT: Hinden@BBN-UNIX

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

STATUS: Elective

SPECIFICATION: IEN 158

COMMENTS:

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

This specification should be updated and reissued as an RFC.

OTHER REFERENCES:

RFC643

DEPENDENCIES: Internet Protocol

CONTACT: Postel@USC-ISIF

Official Protocols RFC880

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

STATUS: Experimental

SPECIFICATION: RFC827

COMMENTS:

The gateway protocol now under development.

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

OTHER REFERENCES:

DEPENDENCIES: Internet Protocol

CONTACT: Mills@USC-ISID

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

STATUS: Experimental

SPECIFICATION: RFC823

COMMENTS:

The gateway protocol now used in the core gateways.

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

OTHER REFERENCES:

DEPENDENCIES: Internet Protocol

CONTACT: Brescia@BBN-UNIX

Official Protocols RFC880

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

STATUS: Experimental

SPECIFICATION: IEN 90

COMMENTS:

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

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

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

OTHER REFERENCES:

DEPENDENCIES: Internet Protocol

CONTACT: Postel@USC-ISIF

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

STATUS: Experimental

SPECIFICATION: IEN 119

COMMENTS:

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

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

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

OTHER REFERENCES:

DEPENDENCIES: Internet Protocol

CONTACT: Forgie@BBN

Official Protocols RFC880

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

STATUS: Experimental

SPECIFICATION: RFCxxx

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:

DEPENDENCIES: Internet Protocol, Stream Protocol

CONTACT: Casner@USC-ISIB

Application Level

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

STATUS: Recommended

SPECIFICATION: RFC854 (in "Internet Telnet Protocol and
Options")

COMMENTS:

The protocol for remote terminal access.

This has been revised since the IPTW. RFC764 in IPTW is now
obsolete.

OTHER REFERENCES:

DEPENDENCIES: Transmission Control Protocol

CONTACT: Postel@USC-ISIF

Official Protocols RFC880

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

STATUS: Elective

SPECIFICATION: General description of options: RFC855
(in "Internet Telnet Protocol and Options")

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

(obs = obsolete)

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

COMMENTS:

The Binary Transmission, Echo, Suppress Go Ahead, Status,
Timing Mark, and Extended Options List options have been
recently updated and reissued. These are the most frequently
implemented options.

Official Protocols RFC880

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

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

OTHER REFERENCES:

DEPENDENCIES: Telnet

CONTACT: Postel@USC-ISIF

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

STATUS: Recommended

SPECIFICATION: RFC765 (in IPTW)

COMMENTS:

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

There are a number of minor corrections to be made. A major
change is the deletion of the mail commands, and a major
clarification is needed in the discussion of the management of
the data connection. Also, a suggestion has been made to
include some directory manipulation commands (RFC775).

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

Data Connection Management:

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

b. Negotiating Non-Default Data Ports: The User-PI may
specify a non-default user side data port with the PORT
command. The User-PI may request the server side to
identify a non-default server side data port with the PASV
command. Since a connection is defined by the pair of
addresses, either of these actions is enough to get a
different data connection, still it is permitted to do both

Official Protocols RFC880

commands to use new ports on both ends of the data
connection.

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

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

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

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

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

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

LIST and NLST:

There is some confusion about the LIST an NLST commands, and
what is appropriate to return. Some clarification and

Official Protocols RFC880

motivation for these commands should be added to the
specification.

OTHER REFERENCES:

RFC678 - Document File Format Standards

DEPENDENCIES: Transmission Control Protocol

CONTACT: Postel@USC-ISIF

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

STATUS: Elective

SPECIFICATION: RFC783 (in IPTW)

COMMENTS:

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

No known problems with this specification. This is in use in
several local networks.

OTHER REFERENCES:

DEPENDENCIES: User Datagram Protocol

CONTACT: Postel@USC-ISIF

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

STATUS: Recommended

SPECIFICATION: RFC821 (in "Internet Mail Protocols")

COMMENTS:

The procedure for transmitting computer mail between hosts.

This has been revised since the IPTW, it is in the "Internet
Mail Protocols" volume of November 1982. 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 [ISIF]<SMTP>MAIL.ERRORS.

Official Protocols RFC880

Some minor differences between RFC821 and RFC822 should be
resolved.

OTHER REFERENCES:

RFC822 - Mail Header Format Standards

This has been revised since the IPTW, it is in the "Internet
Mail Protocols" volume of November 1982. RFC733 (in IPTW)
is obsolete. Further revision of RFC822 is needed to
correct some minor errors in the details of the
specification.

DEPENDENCIES: Transmission Control Protocol

CONTACT: Postel@USC-ISIF

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

STATUS: Elective

SPECIFICATION: RFC407 (in APH)

COMMENTS:

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

Some changes needed for use with TCP.

No known active implementations.

OTHER REFERENCES:

DEPENDENCIES: File Transfer Protocol
Transmission Control Protocol

CONTACT: Postel@USC-ISIF

Official Protocols RFC880

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

STATUS: Elective

SPECIFICATION: RFC740 (in APH)

COMMENTS:

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

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

Revision in progress.

OTHER REFERENCES:

DEPENDENCIES: Transmission Control Protocol

CONTACT: Braden@USC-ISIA

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

STATUS: Elective

SPECIFICATION: RFC818

COMMENTS:

Provides special access to user Telnet on a remote system.

OTHER REFERENCES:

DEPENDENCIES: Telnet, Transmission Control Protocol

CONTACT: Postel@USC-ISIF

Official Protocols RFC880

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

STATUS: Elective

SPECIFICATION: NIC 24308 (in APH)

COMMENTS:

The protocols for vector graphics.

Very minor changes needed for use with TCP.

No known active implementations.

OTHER REFERENCES:

DEPENDENCIES: Telnet, Transmission Control Protocol

CONTACT: Postel@USC-ISIF

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

STATUS: Recommended

SPECIFICATION: RFC862

COMMENTS:

Debugging protocol, sends back whatever you send it.

OTHER REFERENCES:

DEPENDENCIES: Transmission Control Protocol
or User Datagram Protocol

CONTACT: Postel@USC-ISIF

Official Protocols RFC880

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

STATUS: Elective

SPECIFICATION: RFC863

COMMENTS:

Debugging protocol, throws away whatever you send it.

OTHER REFERENCES:

DEPENDENCIES: Transmission Control Protocol
or User Datagram Protocol

CONTACT: Postel@USC-ISIF

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

STATUS: Elective

SPECIFICATION: RFC864

COMMENTS:

Debugging protocol, sends you ASCII data.

OTHER REFERENCES:

DEPENDENCIES: Transmission Control Protocol
or User Datagram Protocol

CONTACT: Postel@USC-ISIF

Official Protocols RFC880

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

STATUS: Elective

SPECIFICATION: RFC865

COMMENTS:

Debugging protocol, sends you a short ASCII message.

OTHER REFERENCES:

DEPENDENCIES: Transmission Control Protocol
or User Datagram Protocol

CONTACT: Postel@USC-ISIF

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

STATUS: Elective

SPECIFICATION: RFC866

COMMENTS:

Lists the currently active users.

OTHER REFERENCES:

DEPENDENCIES: Transmission Control Protocol
or User Datagram Protocol

CONTACT: Postel@USC-ISIF

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

STATUS: Elective

SPECIFICATION: RFC742 (in APH)

COMMENTS:

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

Some extensions have been suggested.

Some changes are are needed for TCP.

Official Protocols RFC880

OTHER REFERENCES:

DEPENDENCIES: Transmission Control Protocol

CONTACT: Postel@USC-ISIF

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

STATUS: Elective

SPECIFICATION: RFC812 (in IPTW)

COMMENTS:

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

OTHER REFERENCES:

DEPENDENCIES: Transmission Control Protocol

CONTACT: Feinler@SRI-NIC

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

STATUS: Elective

SPECIFICATION: RFC811 (in IPTW)

COMMENTS:

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

OTHER REFERENCES:

RFC810 - Host Table Specification

DEPENDENCIES: Transmission Control Protocol

CONTACT: Feinler@SRI-NIC

Official Protocols RFC880

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

STATUS: Experimental

SPECIFICATION: IEN 116 (in IPTW)

COMMENTS:

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

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

Work is in progress on a significant revision. Further
implementations of this protocol are not advised.

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

OTHER REFERENCES:

DEPENDENCIES: User Datagram Protocol

CONTACT: Postel@USC-ISIF

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

STATUS: Experimental

SPECIFICATION: CS-DN-2

COMMENTS:

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

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

OTHER REFERENCES:

DEPENDENCIES: Transmission Control Protocol

CONTACT: Solomon@UWISC

Official Protocols RFC880

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

STATUS: Elective

SPECIFICATION: RFC867

COMMENTS:

Provides the day and time in ASCII character string.

OTHER REFERENCES:

DEPENDENCIES: Transmission Control Protocol
or User Datagram Protocol

CONTACT: Postel@USC-ISIF

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

STATUS: Recommended

SPECIFICATION: RFC868

COMMENTS:

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

OTHER REFERENCES:

DEPENDENCIES: Transmission Control Protocol
or User Datagram Protocol

CONTACT: Postel@USC-ISIF

Official Protocols RFC880

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

STATUS: Elective

SPECIFICATION: RFC778

COMMENTS:

Provides a mechanism for keeping synchronized clocks.

OTHER REFERENCES:

DEPENDENCIES: Internet Control Message Protocol

CONTACT: Mills@USC-ISID

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

STATUS: Elective

SPECIFICATION: RFC734 (in APH)

COMMENTS:

A special Telnet like protocol for display terminals.

OTHER REFERENCES:

DEPENDENCIES: Transmission Control Protocol

CONTACT: Admin.MRC@SU-SCORE

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

STATUS: Experimental

SPECIFICATION: RFC759

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:

RFC767 - Structured Document Formats

Official Protocols RFC880

DEPENDENCIES: Transmission Control Protocol

CONTACT: Postel@USC-ISIF

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

STATUS: Elective

SPECIFICATION: RFC569

COMMENTS:

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

OTHER REFERENCES:

DEPENDENCIES:

CONTACT: Postel@USC-ISIF

Appendices

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

STATUS: None

SPECIFICATION: RFC870

COMMENTS:

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

Issued October 1983, replaces RFC790 in IPTW, and RFC820 of
January 1983.

OTHER REFERENCES:

CONTACT: JKReynolds@USC-ISIF

Official Protocols RFC880

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

STATUS: Elective

SPECIFICATION: RFC794 (in IPTW)

COMMENTS:

Describes how to do pre-emption of TCP connections.

OTHER REFERENCES:

CONTACT: Postel@USC-ISIF

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

STATUS: None

SPECIFICATION: RFC795 (in IPTW)

COMMENTS:

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

Out of date, needs revision.

OTHER REFERENCES:

CONTACT: Postel@USC-ISIF

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

STATUS: None

SPECIFICATION: RFC796 (in IPTW)

COMMENTS:

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

Out of date, needs revision.

OTHER REFERENCES:

CONTACT: Postel@USC-ISIF

Official Protocols RFC880

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

STATUS: Recommended

SPECIFICATION: RFC877

COMMENTS:

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

OTHER REFERENCES:

CONTACT: jtk@PURDUE

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