Network Working Group G. Malkin
Request for Comments: 1206 FTP Software, Inc.
FYI: 4 A. Marine
Obsoletes: RFC 1177 SRI
February 1991 FYI on Questions and Answers
Answers to Commonly asked "New Internet User" Questions
Status of this Memo
This FYI RFC is one of two FYI's called, "Questions and Answers"
(Q/A), produced by the User Services Working Group of the Internet
Engineering Task Force (IETF). The goal is to document the most
commonly asked questions and answers in the Internet.
This memo provides information for the Internet community. It does
not specify any standard. Distribution of this memo is unlimited.
Table of Contents
1. Introduction................................................. 12. Acknowledgements............................................. 23. Questions About the Internet................................. 24. Questions About TCP/IP....................................... 45. Questions About the Domain Name System....................... 46. Questions About Internet Documentation....................... 57. Questions about Internet Organizations and Contacts.......... 98. Questions About Services..................................... 139. Mailing Lists................................................ 1610. Miscellaneous "Internet lore" questions..................... 1711. Suggested Reading........................................... 1812. References.................................................. 1913. Condensed Glossary.......................................... 2014. Security Considerations..................................... 3115. Authors' Addresses.......................................... 321. Introduction
New users joining the Internet community have the same questions as
did everyone else who has ever joined. Our quest is to provide the
Internet community with up to date, basic Internet knowledge and
experience, while moving the redundancies away from the electronic
mailing lists so that the lists' subscribers do not have to read the
same queries and answers over and over again.
Future updates of this memo will be produced as User Services members
become aware of additional questions that should be included, and of
deficiencies or inaccuracies that should be amended in this document.
An additional FYI Q/A will be published which will deal with
intermediate and advanced Q/A topics.
The Q/A mailing lists are maintained by Gary Malkin at FTP.COM. They
are used by a subgroup of the User Services Working Group to discuss
the Q/A FYIs. They include:
email@example.com This is a discussion mailing list. Its
primary use is for pre-release review of
the Q/A FYIs.
firstname.lastname@example.org This is how you join the quail mailing list.
email@example.com This is a write-only list which serves as a
repository for candidate questions and answers.
It is not necessary to be on the quail mailing
list to forward to the quail-box.
The following people deserve thanks for their help and contributions
to this FYI Q/A: Vint Cerf (CNRI), Ralph Droms (Bucknell),
Tracy LaQuey Parker (UTexas), Craig Partridge (SICS), Jon Postel (ISI),
Joyce K. Reynolds (ISI), Karen Roubicek (BBNST), Marty Schoffstall
(PSI, Inc.), Patricia Smith (Merit), Gene Spafford (Purdue) and
James Van Bokkelen (FTP Software, Inc.).
3. Questions About the Internet
What is the Internet?
The Internet is a large collection of networks (all of which run
the TCP/IP protocols) that are tied together so that users of any
of the networks can use the network services provided by TCP/IP to
reach users on any of the other networks. The Internet started
with the ARPANET, but now includes such networks as NSFNET,
NYSERnet, and thousands of others. There are other major wide
area networks, such as BITNET and DECnet networks, that are not
based on the TCP/IP protocols and are thus not part of the
Internet. However, it is possible to communicate between them and
the Internet via electronic mail because of mail gateways that act
as "translators" between the different network protocols involved.
Note: You will often see "internet" with a small "i". This could
refer to any network built based on TCP/IP, or might refer to
networks using other protocol families that are composites built
of smaller networks.
I just got on the Internet. What can I do now?
You now have access to all the resources you are authorized to use
on your own Internet host, on any other Internet host on which you
have an account, and on any other Internet host that offers
publicly accessible information. The Internet gives you the
ability to move information between these hosts via file
transfers. Once you are logged into one host, you can use the
Internet to open a connection to another, login, and use its
services interactively (this is known as remote login or
"TELNETTING". In addition, you can send electronic mail to users
at any Internet site and to users on many non-Internet sites that
are accessible via electronic mail.
There are various other services you can use. For example, some
hosts provide access to specialized databases or to archives of
information. The Internet Resource Guide provides information
regarding some of these sites. The Internet Resource Guide lists
facilities on the Internet that are available to users. Such
facilities include supercomputer centers, library catalogs and
specialized data collections. The guide is published by the NSF
Network Service Center (NNSC) and is continuously being updated.
The Resource Guide is distributed free via e-mail (send a note to
firstname.lastname@example.org to join the e-mail
distribution) and via anonymous FTP (in nnsc.nsf.net:resource-
guide/*). Hardcopy is available at a nominal fee (to cover
reproduction costs) from the NNSC. Call the NNSC at 617-873-3400
for more information.
How do I find out if a site has a computer on the Internet?
Three good sources to consult are "!%@:: A Directory of Electronic
Mail Addressing and Networks" by Donnalyn Frey and Rick Adams;
"The User's Directory of Computer Networks", by Tracy LaQuey; and
"The Matrix: Computer Networks and Conferencing Systems
Worldwide", by John Quarterman.
In addition, it is possible to find some information about
Internet sites in the WHOIS database maintained at the DDN NIC at
SRI International. The DDN NIC (Defense Data Network, Network
Information Center) provides an information retrieval interface to
the database that is also called WHOIS. To use this interface,
TELNET to NIC.DDN.MIL and type "whois" (carriage return). No
login is necessary. Type "help" at the whois prompt for more
information on using the facility. WHOIS will show many sites,
but may not show every site registered with the DDN NIC (simply
for reasons having to do with how the program is set up to search
4. Questions About TCP/IP
What is TCP/IP?
TCP/IP (Transmission Control Protocol/Internet Protocol) [4,5,6]
is the common name for a family of over 100 data-communications
protocols used to organize computers and data-communications
equipment into computer networks. TCP/IP was developed to
interconnect hosts on ARPANET, PRNET (packet radio), and SATNET
(packet satellite). All three of these networks have since been
retired; but TCP/IP lives on. It is currently used on a large
international network of networks called the Internet, whose
members include universities, other research institutions,
government facilities, and many corporations. TCP/IP is also
sometimes used for other networks, particularly local area
networks that tie together numerous different kinds of computers
or tie together engineering workstations.
What are the other well-known standard protocols
in the TCP/IP family?
Other than TCP and IP, the three main protocols in the TCP/IP
suite are the Simple Mail Transfer Protocol (SMTP) , the File
Transfer Protocol (FTP) , and the TELNET Protocol . There
are many other protocols in use on the Internet. The Internet
Activities Board (IAB) regularly publishes an RFC  that
describes the state of standardization of the various Internet
protocols. This document is the best guide to the current status
of Internet protocols and their recommended usage.
5. Questions About the Domain Name System
What is the Domain Name System?
The Domain Name System (DNS) is a hierarchical, distributed method
of organizing the name space of the Internet. The DNS
administratively groups hosts into a hierarchy of authority that
allows addressing and other information to be widely distributed
and maintained. A big advantage to the DNS is that using it
eliminates dependence on a centrally-maintained file that maps
host names to addresses.
What is a Fully Qualified Domain Name?
A Fully Qualified Domain Name (FQDN) is a domain name that
includes all higher level domains relevant to the entity named.
If you think of the DNS as a tree-structure with each node having
its own label, a Fully Qualified Domain Name for a specific node
would be its label followed by the labels of all the other nodes
between it and the root of the tree. For example, for a host, a
FQDN would include the string that identifies the particular host,
plus all domains of which the host is a part up to and including
the top-level domain (the root domain is always null). For
example, PARIS.NISC.SRI.COM is a Fully Qualified Domain Name for
the host at 220.127.116.11. In addition, NISC.SRI.COM is the FQDN
for the NISC domain.
6. Questions About Internet Documentation
What is an RFC?
The Request for Comments documents (RFCs) are working notes of the
Internet research and development community. A document in this
series may be on essentially any topic related to computer
communication, and may be anything from a meeting report to the
specification of a standard. Submissions for Requests for
Comments may be sent to the RFC Editor, Jon Postel
Most RFCs are the descriptions of network protocols or services,
often giving detailed procedures and formats for their
implementation. Other RFCs report on the results of policy
studies or summarize the work of technical committees or
workshops. All RFCs are considered public domain unless
explicitly marked otherwise.
While RFCs are not refereed publications, they do receive
technical review from either the task forces, individual technical
experts, or the RFC Editor, as appropriate. Currently, most
standards are published as RFCs, but not all RFCs specify
Anyone can submit a document for publication as an RFC.
Submissions must be made via electronic mail to the RFC Editor.
Please consult RFC 1111, "Instructions to RFC Authors" , for
further information. RFCs are accessible online in public access
files, and a short message is sent to a notification distribution
list indicating the availability of the memo. Requests to be
added to this distribution list should be sent to RFC-
The online files are copied by interested people and printed or
displayed at their sites on their equipment. (An RFC may also be
returned via electronic mail in response to an electronic mail
query.) This means that the format of the online files must meet
the constraints of a wide variety of printing and display
Once a document is assigned an RFC number and published, that RFC
is never revised or re-issued with the same number. There is
never a question of having the most recent version of a particular
RFC. However, a protocol (such as File Transfer Protocol (FTP))
may be improved and re-documented many times in several different
RFCs. It is important to verify that you have the most recent RFC
on a particular protocol. The "IAB Official Protocol Standards"
 memo is the reference for determining the correct RFC to refer
to for the current specification of each protocol.
How do I obtain RFCs?
RFCs can be obtained via FTP from NIC.DDN.MIL, with the pathname
RFC:RFCnnnn.TXT or RFC:RFCnnnn.PS (where "nnnn" refers to the
number of the RFC). Login using FTP, username "anonymous" and
password "guest". The NIC also provides an automatic mail service
for those sites which cannot use FTP. Address the request to
SERVICE@NIC.DDN.MIL and in the subject field of the message
indicate the RFC number, as in "Subject: RFC nnnn" (or "Subject:
RFC nnnn.PS" for PostScript RFCs).
RFCs can also be obtained via FTP from NIS.NSF.NET. Using FTP,
login with username "anonymous" and password "guest"; then connect
to the RFC directory ("cd RFC"). The file name is of the form
RFCnnnn.TXT-1 (where "nnnn" refers to the number of the RFC). The
NIS also provides an automatic mail service for those sites which
cannot use FTP. Address the request to NIS-INFO@NIS.NSF.NET and
leave the subject field of the message blank. The first line of
the text of the message must be "SEND RFCnnnn.TXT-1", where nnnn
is replaced by the RFC number.
Requests for special distribution should be addressed to either
the author of the RFC in question, or to NIC@NIC.DDN.MIL. SRI
International operates NIC.DDN.MIL and has a hardcopy subscription
service for RFCs as well as several publications which incorporate
a selection of RFCs defining Internet standards. Unless
specifically noted otherwise on the RFC itself, all RFCs are for
How do I obtain a list of RFCs?
The NIC maintains a file that is an index of the RFCs. It lists
each RFC, starting with the most recent, and for each RFC provides
the number, title, author(s), issue date, and number of hardcopy
pages. In addition, it lists the online formats (PostScript or
ASCII text) for each RFC and the number of bytes each such version
is online on the NIC.DDN.MIL host. If an RFC is also an FYI, that
fact is noted, with the corresponding FYI number. (There is a
parallel FYI Index available). Finally, the Index notes whether
or not an RFC is obsoleted or updated by another RFC, and gives
the number of that RFC, or if an RFC itself obsoletes or updates
another RFC, and gives that RFC number. The index is updated
online each time an RFC is issued.
This RFC Index is available online from the NIC.DDN.MIL host as
RFC:RFC-INDEX.TXT. The FYI Index is online as FYI:FYI-INDEX.TXT.
It is also available from the NIC in hardcopy for $10, as are
individual RFCs. Call the NIC at 1-800-235-3155 for help in
obtaining the file.
Which RFCs are Standards?
See "IAB Official Protocol Standards" (currently, RFC 1140) .
What is an Internet Draft? Are there any guidelines available for
Internet Drafts (I-D's) are the current working documents of the
IETF. Internet Drafts are generally in the format of an RFC with
some key differences:
- The Internet Drafts are not RFC's and are not a numbered
- The words INTERNET-DRAFT appear in place of RFC XXXX
in the upper left-hand corner.
- The document does not refer to itself as an RFC or as a
- An Internet Draft does not state nor imply that it is a
proposed standard. To do so conflicts with the role of
the IAB, the RFC Editor, and the Internet Engineering
Steering Group (IESG).
An Internet Drafts Directory has been installed to make available,
for review and comment by the IETF members, draft documents that
will be submitted ultimately to the IAB and the RFC Editor to be
considered for publishing as an RFC. The Internet Drafts
Directories are maintained primarily at the NSFNET Network Service
Center (NNSC). There are several "shadow" machines which contain
the IETF and Internet Drafts Directories. They are:
NSF Network Service Center: nnsc.nsf.net
DDN NIC: nic.ddn.mil
Pacific Rim: munnari.oz.au
Europe: nic.nordu.net (18.104.22.168)
To access these directories, use anonymous FTP. Login with
username, "anonymous", password, "guest". Once logged in, change
to the directory, "cd internet-drafts". Internet Draft files can
then be retrieved.
For further information on the Internet Drafts of the IETF, or if
you have problems with retrieving Internet Draft documents,
contact Megan Davies (email@example.com) or Greg Vaudreuil
(firstname.lastname@example.org) for assistance.
How do I obtain OSI Standards documents?
OSI Standards documents are NOT available from the Internet via
anonymous FTP due to copyright restrictions. These are available
Omnicom Information Service
501 Church Street NE
Vienna, VA 22180 USA
Telephone: (800) 666-4266 or (703) 281-1135
Fax: (703) 281-1505
However, the GOSIP specification which covers the use of OSI
protocols within the U.S. Government is available from the NIC and
from the National Institute of Standards and Technology (NIST).
The final text of GOSIP Version 2 is now available from both
sites. Version 2 is expected to become a Federal Information
Processing Standard (FIPS) in early 1991.
Available through anonymous ftp from osi.ncsl.nist.gov
./pub/gosip/gosip_v2.txt -- ascii
./pub/gosip/gosip_v2.txt.Z -- ascii compressed
./pub/gosip/gosip_v2.ps -- PostScript
./pub/gosip/gosip_v2.ps.Z -- PostScript compressed
Available through anonymous ftp from nic.ddn.mil (22.214.171.124)
PROTOCOLS:GOSIP-V2.TXT -- ascii
PROTOCOLS:GOSIP-V2.PS -- PostScript
Standards Processing Coordinator (ADP)
National Institute of Standards and Technology
Technology Building, Room B-64
Gaithersburg, MD 20899
Network Information Systems Center
SRI International, Room EJ291
333 Ravenswood Ave.
Menlo Park, CA 94025
7. Questions about Internet Organizations and Contacts
What is the IAB?
The Internet Activities Board (IAB) is the coordinating committee
for Internet design, engineering and management . IAB members
are deeply committed to making the Internet function effectively
and evolve to meet a large scale, high speed future. The chairman
serves a term of two years and is elected by the members of the
IAB. The current Chair of the IAB is Vint Cerf. The IAB focuses
on the TCP/IP protocol suite, and extensions to the Internet
system to support multiple protocol suites.
The IAB performs the following functions:
1) Sets Internet Standards,
2) Manages the RFC publication process,
3) Reviews the operation of the IETF and IRTF,
4) Performs strategic planning for the Internet, identifying
long-range problems and opportunities,
5) Acts as an international technical policy liaison and
representative for the Internet community, and
6) Resolves technical issues which cannot be treated within
the IETF or IRTF frameworks.
The IAB has two principal subsidiary task forces:
1) Internet Engineering Task Force (IETF)
2) Internet Research Task Force (IRTF)
Each of these Task Forces is led by a chairman and guided by a
Steering Group which reports to the IAB through its chairman. For
the most part, a collection of Research or Working Groups carries
out the work program of each Task Force.
All decisions of the IAB are made public. The principal vehicle
by which IAB decisions are propagated to the parties interested in
the Internet and its TCP/IP protocol suite is the Request for
Comments (RFC) note series and the Internet Monthly Report.
What is the IANA?
The task of coordinating the assignment of values to the
parameters of protocols is delegated by the Internet Activities
Board (IAB) to the Internet Assigned Numbers Authority (IANA).
These protocol parameters include op-codes, type fields, terminal
types, system names, object identifiers, and so on. The "Assigned
Numbers" Request for Comments (RFC)  documents the currently
assigned values from several series of numbers used in network
protocol implementations. Internet addresses and Autonomous
System numbers are assigned by the Network Information Center at
SRI International. This responsibility has been delegated by the
IANA to the DDN NIC which serves as the Internet Registry. The
IANA is located at USC/Information Sciences Institute.
Current types of assignments listed in Assigned Numbers and
maintained by the IANA are:
Address Resolution Protocol Parameters
ARPANET and MILNET X.25 Address Mappings
ARPANET and MILNET Logical Addresses
ARPANET and MILNET Link Numbers
BOOTP Parameters and BOOTP Extension Codes
Domain System Parameters
IANA Ethernet Address Blocks
Ethernet Numbers of Interest
IEEE 802 Numbers of Interest
Internet Protocol Numbers
Internet Version Numbers
IP Time to Live Parameter
IP TOS Parameters
Mail Encryption Types
Network Management Parameters
Point-to-Point Protocol Field Assignments
PRONET 80 Type Numbers
Protocol and Service Names
Protocol/Type Field Assignments
Public Data Network Numbers
Reverse Address Resolution Protocol Operation Codes
Terminal Type Names
X.25 Type Numbers
For more information on number assignments, contact IANA@ISI.EDU.
What is a NIC? What is a NOC?
"NIC" stands for Network Information Center. It is an
organization which provides network users with information about
services provided by the network.
"NOC" stands Network Operations Center. It is an organization
that is responsible for maintaining a network.
For many networks, especially smaller, local networks, the
functions of the NIC and NOC are combined. For larger networks,
such as mid-level and backbone networks, the NIC and NOC
organizations are separate, yet they do need to interact to fully
perform their functions.
What is "The NIC"?
"The NIC" is the Defense Data Network, Network Information Center
(DDN NIC) at SRI International, which is a network information
center which holds a primary repository for RFCs and Internet
Drafts. The host name is NIC.DDN.MIL. Shadow copies of the RFCs
and the Internet Drafts are maintained by the NSFNET on
The DDN NIC also provides various user assistance services for DDN
users; contact NIC@NIC.DDN.MIL or call 1-800-235-3155 for more
information. In addition, the DDN NIC is the Internet
registration authority for the root domain and several top and
second level domains; maintains the official DoD Internet Host
Table; is the site of the Internet Registry (IR); and maintains
the WHOIS database of network users, hosts, domains, networks, and
Points of Contact.
What is the IR?
The Internet Registry (IR) is the organization that is responsible
for assigning identifiers, such as IP network numbers and
autonomous system numbers, to networks. The IR also gathers and
registers such assigned information. The IR may, in the future,
allocate the authority to assign network identifiers to other
organizations; however, it will continue to gather data regarding
such assignments. At present, the DDN NIC at SRI International
serves as the IR.
What is the IETF?
The Internet has grown to encompass a large number of widely
geographically dispersed networks in academic and research
communities. It now provides an infrastructure for a broad
community with various interests. Moreover, the family of
Internet protocols and system components has moved from
experimental to commercial development. To help coordinate the
operation, management and evolution of the Internet, the IAB
established the Internet Engineering Task Force (IETF).
The IETF is chaired by Phill Gross and managed by its Internet
Engineering Steering Group (IESG). The IETF is a large open
community of network designers, operators, vendors, and
researchers concerned with the Internet and the Internet protocol
suite. It is organized around a set of several technical areas,
each managed by a technical area director. In addition to the
IETF Chairman, the area directors make up the IESG membership.
The IAB has delegated to the IESG the general responsibility for
making the Internet work and for the resolution of all short- and
mid-range protocol and architectural issues required to make the
Internet function effectively.
What is the IRTF?
To promote research in networking and the development of new
technology, the IAB established the Internet Research Task Force
In the area of network protocols, the distinction between research
and engineering is not always clear, so there will sometimes be
overlap between activities of the IETF and the IRTF. There is, in
fact, considerable overlap in membership between the two groups.
This overlap is regarded as vital for cross-fertilization and
The IRTF is a community of network researchers, generally with an
Internet focus. The work of the IRTF is governed by its Internet
Research Steering Group (IRSG). The chairman of the IRTF and IRSG
is David Clark.
8. Questions About Services
How do I find someone's electronic mail address?
There are a number of directories on the Internet; however, all of
them are far from complete. The largest directories are the WHOIS
database at the DDN NIC, the PSInet White Pages, and KNOWBOT.
Generally, it is still necessary to ask the person for his or her
How do I use the WHOIS program at the DDN NIC?
To use the WHOIS program to search the WHOIS database at the DDN
NIC, TELNET to the NIC host, NIC.DDN.MIL. There is no need to
login. Type "whois" to call up the information retrieval program.
Next, type the name of the person, host, domain, network, or
mailbox for which you need information. If you are only typing
part of the name, end your search string with a period. Type
"help" for a more in-depth explanation of what you can search for
and how you can search. If you have trouble, send a message to
NIC@NIC.DDN.MIL or call 1-800-235-3155. Bug reports can be sent
to BUG-WHOIS@NIC.DDN.MIL and suggestions for improvements to the
program can be sent to SUGGESTIONS@NIC.DDN.MIL.
How do I become registered in the DDN NIC's WHOIS database?
If you would like to be listed in the WHOIS database, you must
have an electronic mailbox accessible from the Internet. First
obtain the file NETINFO:USER-TEMPLATE.TXT. You can either
retrieve this file via anonymous FTP from NIC.DDN.MIL or get it
through electronic mail. To obtain the file via electronic mail,
send a message to SERVICE@NIC.DDN.MIL and put the file name in the
subject line of the message; that is, "Subject: NETINFO USER-
TEMPLATE.TXT". The file will be returned to you overnight.
Fill out the name and address information requested in the file
and return it to REGISTRAR@NIC.DDN.MIL. Your application will be
processed and you will be added to the database. Unless you are
an official Point of Contact for a network entity registered at
the DDN NIC, the DDN NIC will not regularly poll you for updates,
so you should remember to send corrections to your information as
your contact data changes.
How do I use the White Pages at PSI?
Performance Systems International, Inc. (PSI), sponsors a White
Pages Pilot Project that collects personnel information from
member organizations into a database and provides online access to
that data. This effort is based on the OSI X.500 Directory
To access the data, TELNET to WP.PSI.COM and login as "fred" (no
password is necessary). You may now look up information on
participating organizations. The program provides help on usage.
For example, typing "help" will show you a list of commands,
"manual" will give detailed documentation, and "whois" will
provide information regarding how to find references to people.
For a list of the organizations that are participating in the
pilot project by providing information regarding their members,
type "whois -org *".
For more information, send a message to WP-INFO@PSI.COM.
How do I use the Knowbot Information Service?
The Knowbot Information Service is a white pages "meta-service"
that provides a uniform interface to heterogeneous white pages
services in the Internet. Using the Knowbot Information Service,
you can form a single query that can search for white pages
information from the NIC WHOIS service, the CSNET WHOIS service,
the PSI White Pages Pilot Project, and MCI Mail, among others, and
have the responses displayed in a single, uniform format.
Currently, the Knowbot Information Service can be accessed through
TELNET to port 185 on hosts nri.reston.va.us and sol.bucknell.edu.
From a UNIX host, use "telnet nri.reston.va.us 185". There is
also an electronic mail interface avaliable by sending mail to
netaddress at either nri.reston.va.us or sol.bucknell.edu.
The commands "help" and "man" summarize the command interface.
Simply entering a user name at the prompt searches a default list
of Internet directory services for the requested information.
Organization and country information can be included thorgh the
syntax: "email@example.com". For example, the queries
"droms@bucknell" and "firstname.lastname@example.org" are both valid. Note that
these are not Domain Names, but rather a syntax to specify an
organization and a country for the search.
The default list of directory services currently includes the
whois services at the SRI NIC and the CSNET NIC and the white
pages service for MCIMail. If an organization is specified, the
PSI X.500 service is also searched. Other services can be
What is Usenet? What is Netnews?
Usenet and Netnews are common names of a distributed computer
bulletin board system that some computers on the Internet
participate in. It is not strictly an Internet service: many
computers not on the Internet also participate. Netnews can be a
valuable tool to economize what might otherwise be a large volume
of traffic from electronic mailing lists.
How do I get on Usenet? How do I get Netnews on my computer?
To get on Usenet, you must acquire the software, which is
available for some computers at no cost from some anonymous FTP
sites across the Internet, and you must find an existing Usenet
site that is willing to support a connection to your computer. In
many cases, this "connection" merely represents additional traffic
over existing Internet access channels.
What is anonymous FTP?
Anonymous FTP is a conventional way of allowing you to sign on to
a computer on the Internet and copy specified public files from it
. Some sites offer anonymous FTP to distribute software and
various kinds of information. You use it like any FTP, but the
username is "anonymous". Many systems will allow any password and
request that the password you choose is your userid. If this
fails, the generic password is usually "guest".
What is "TELNET"?
The term "TELNET" refers to the remote login that's possible on
the Internet because of the TELNET Protocol . The use of this
term as a verb, as in "telnet to a host" means to establish a
connection across the Internet from one host to another. Usually,
you must have an account on the remote host to be able to login to
it once you've made a connection. However, some hosts, such as
those offering white pages directories, provide public services
that do not require a personal account.
9. Mailing Lists
What is a mailing list?
A mailing list is really nothing more than an alias that has
multiple destinations. Mailing lists are usually created to
discuss specific topics. Anybody interested in that topic, may
(usually) join that list. Some mailing lists have membership
restrictions, others have message content restrictions, and still
others are moderated. Most large, "public" mailing lists, such as
IETF and TCP-IP, have an additional mail address to which requests
to be added or deleted may be sent. Usually, these are of the
There is a "list-of-lists" file available on the host
ftp.nisc.sri.com that lists most of the major mailing lists,
describes their primary topics, and explains how to subscribe to
them. The file is available for anonymous ftp in the netinfo
directory as interest-groups (that is, the path is:
netinfo/interest-groups). It can also be obtained via electronic
mail. Send a message to email@example.com with the body of
the message reading, "Send netinfo/interest-groups" and the file
will be returned in moderate size pieces via electronic mail.
How do I contact the administrator of a mailing list rather than
posting to the entire list?
For every mailing list mentioned in the "interest-groups" file, there
is a description of how to join the list or send other such
administrative messages to the person in charge of the list. In
general, however, it is usually safe to assume that you can send a
message to an address in the format of ListName-request@domain. The
convention of having a parallel mailbox conforming to the
"-request" format is very widely followed. All administrative
messages regarding using, joining, or quitting the list should be
sent to that mailbox instead of to the whole list so that the readers
of the list don't have to read them.
What are some good mailing lists or news groups?
The TCP-IP, IETF, and RFC Distribution lists are primary lists for new
Internet users who desire further information about current and
emerging developments in the Internet. The first two lists are
unmoderated discussion lists, and the latter is an announcement
service used by the RFC Editor.
How do I subscribe to the TCP-IP mailing list?
To be added to the TCP-IP mailing list, send a message to:
How do I subscribe to the IETF mailing list?
To be added to the IETF mailing list, send a message to:
How do I subscribe to the RFC Distribution list?
To be added to the RFC Distribution list, send a message to:
10. Miscellaneous "Internet lore" questions
What does :-) mean?
In many electronic mail messages, it is sometimes useful to
indicate that part of a message is meant in jest. It is also
sometimes useful to communicate emotion which simple words do not
readily convey. To provide these nuances, a collection of "smiley
faces" has evolved. If you turn your head sideways to the left,
:-) appears as a smiling face. Some of the more common faces are:
:) also a smile
:-X close mouthed
:-o oh, no!
What do "btw", "fyi", "imho", "wrt", and "rtfm" mean?
Often commmon expressions are abbreviated in informal network
postings. These abbreviations stand for "by the way", "for your
information", "in my humble [or honest] opinion", "with respect
to", and "read the f*ing manual" (with the "f" word varying
according to the vehemence of the reader).
What is the "FAQ" list?
This list provides answers to "Frequently Asked Questions" that
often appear on various Usenet newsgroups. The list is posted
every four to six weeks to the news.announce.newusers group. It
is intended to provide a background for new users learning how to
use the news. As the FAQ list provide new users with the answers
to such questions, it helps keep the newsgroups themselves
comparatively free of repetition. Often specific newsgroups will
have and frequently post versions of a FAQ list that are specific
to their topics.
Other information is also routinely posted. Here are the subject
lines of several general information postings provided on Usenet:
Answers to Frequently Asked Questions (the "FAQ" list)
Introduction to news.announce
Rules for posting to Usenet
How to Create a New Newsgroup
How to Create a New Trial Newsgroup
A Primer on How to Work With the Usenet Community
Emily Postnews Answers Your Questions on Netiquette
Hints on writing style for Usenet
USENET Software: History and Sources
List of Active Newsgroups
Alternative Newsgroup Hierarchies
How to Construct the Mailpaths File
Regional Newsgroup Hierarchies
List of Moderators
Publicly Accessible Mailing Lists
List of Periodic Informational Postings
How to Get Information about Networks
A Guide to Social Newsgroups and Mailing Lists
11. Suggested Reading
For further information about the Internet and its protocols in
general, you may choose to obtain copies of the following works:
Bowers, K., T. LaQuey, J. Reynolds, K. Roubicek, M. Stahl, and A.
Yuan, "Where to Start - A Bibliography of General Internetworking
Information", RFC 1175, FYI 3, CNRI, U Texas, ISI, BBN, SRI,
Mitre, August 1990.
Comer, D., "Internetworking with TCP/IP: Principles, Protocols,
and Architecture", Prentice Hall, New Jersey, 1989.
Krol, E., "The Hitchhikers Guide to the Internet", RFC 1118,
University of Illinois Urbana, September 1989.
 Reynolds, J., and J. Postel, "Assigned Numbers", RFC 1060,
USC/Information Sciences Institute, March 1990.
 Postel, J., Editor, "IAB Official Protocol Standards", RFC 1140,
Internet Activities Board, May 1990.
 Postel, J., and J. Reynolds, "File Transfer Protocol (FTP), RFC
959, USC/Information Sciences Institute, October 1985.
 Postel, J., "Internet Protocol - DARPA Internet Program Protocol
Specification", RFC 791, DARPA, September 1981.
 Postel, J., "Transmission Control Protocol - DARPA Internet
Program Protocol Specification", RFC 793, DARPA, September 1981.
 Leiner, B., R. Cole, J. Postel, and D. Mills, "The DARPA Internet
Protocol Suite", IEEE INFOCOM85, Washington D.C., March 1985.
Also in IEEE Communications Magazine, March 1985. Also as
 Cerf, V., "The Internet Activities Board" RFC 1160, CNRI, May
 Postel, J., "Simple Mail Transport Protocol", RFC 788,
USC/Information Sciences Institute, November 1981.
 Postel, J., and J. Reynolds, "TELNET Protocol Specification", RFC
854, USC/Information Sciences Institute, May 1983.
 Postel, J., "Request for Comments on Request for Comments -
Instructions to RFC Authors", RFC 1111, USC/Information Sciences
Institute, August 1989.
13. Condensed Glossary
As with any profession, computers have a particular terminology all
their own. Below is a condensed glossary to assist in making some
sense of the Internet world.
ACM Association for Computer Machinery
A group established in 1947 to promote professional
development and research on computers.
address There are two separate uses of this term in internet
networking: "electronic mail address" and "internet
address". An electronic mail address is the string
of characters that you must give an electronic mail
program to direct a message to a particular person.
See "internet address" for its definition.
AI Artificial Intelligence
The branch of computer science which deals with the
simulation of human intelligence by computer systems.
AIX Advanced Interactive Executive
IBM's version of Unix.
ANSI American National Standards Institute
A group that certifies organizations which develop U.S.
standards for the information processing industry. ANSI
accredited groups participate in defining network protocol
ARP Address Resolution Protocol
An Internet protocol which runs on Ethernet and all IEEE
802.X LANs which maps internet addresses to MAC addresses.
ARPA Advanced Research Projects Agency
The former name of what is now called DARPA.
ARPANET Advanced Research Projects Agency Network
A pioneering long haul network funded by ARPA. It
served as the basis for early networking research as
well as a central backbone during the development of
the Internet. The ARPANET consisted of individual
packet switching computers interconnected by leased lines.
AS Autonomous System
A collection of gateways (routers) under a single
administrative authority using a common Interior Gateway
Protocol for routing packets.
ASCII American Standard Code for Information Interchange
One character of information, usually eight bits wide.
b bit - binary digit
The smallest amount of information which may be stored
in a computer.
BBN Bolt Beranek and Newman, Inc.
The Cambridge, MA company responsible for development,
operation and monitoring of the ARPANET, and later,
the Internet core gateway system, the CSNET Coordination
and Information Center (CIC), and NSFNET Network
Service Center (NNSC).
BITNET Because It's Time Network
BITNET has about 2,500 host computers, primarily at
universities, in many countries. It is managed by
EDUCOM, which provides administrative support and
information services. There are three
main constituents of the network: BITNET in the United
States and Mexico, NETNORTH in Canada, and EARN in
Europe. There are also AsiaNet, in Japan, and
connections in South America. See CREN.
bps bits per second
A measure of data transmission speed.
BSD Berkeley Software Distribution
Term used when describing different versions
of the Berkeley UNIX software, as in "4.3BSD
catenet A network in which hosts are connected to networks
with varying characteristics, and the networks
are interconnected by gateways (routers). The
Internet is an example of a catenet.
CCITT International Telegraph and Telephone
Historically, one of a set of gateways (routers)
operated by the Internet Network Operations Center
at BBN. The core gateway system forms a central part
of Internet routing in that all groups had to advertise
paths to their networks from a core gateway.
CREN The Corporation for Research and Educational Networking
BITNET and CSNET have recently merged to form CREN.
CSNET Computer + Science Network
A large data communications network for institutions doing
research in computer science. It uses several different
protocols including some of its own. CSNET sites include
universities, research laboratories, and commercial
companies. See CREN.
DARPA U.S. Department of Defense Advanced Research Projects Agency
The government agency that funded the ARPANET and later
started the Internet.
The unit transmitted between a pair of internet modules.
The Internet Protocol provides for transmitting blocks of
data, called datagrams, from sources to destinations.
The Internet Protocol does not provide a reliable
communication facility. There are no acknowledgements
either end-to-end or hop-by-hop. There is no error
control for data, only a header checksum. There are
no retransmissions. There is no flow control. See IP.
DCA Defense Communications Agency
The government agency responsible for installation of
the Defense Data Network (DDN), including the ARPANET
and MILNET lines and PSNs. Currently, DCA administers
the DDN, and supports the user assistance and network
registration services of the DDN NIC.
DDN Defense Data Network
Comprises the MILNET and several other DoD networks.
DDN NIC The network information center at SRI International.
It is the primary repository for RFCs and Internet Drafts,
as well as providing other services.
DEC Digital Equipment Corporation
DECnet Digital Equipment Corporation network
A networking protocol for DEC computers and network devices.
A routing table entry which is used to direct any data
addressed to any network numbers not explicitly listed
in the routing table.
DNS The Domain Name System is a mechanism used in
the Internet for translating names of host computers
into addresses. The DNS also allows host computers
not directly on the Internet to have registered
names in the same style, but returns the electronic
mail gateway which accesses the non-Internet network
instead of an IP address.
DOD U.S. Department of Defense
DOE U.S. Department of Energy
dot address (dotted address notation)
Dot address refers to the common notation for Internet
addresses of the form A.B.C.D; where each letter represents,
in decimal, one byte of the four byte IP address.
EARN European Academic Research Network
One of three main constituents of BITNET.
EBCDIC Extended Binary-coded Decimal Interchange Code
EGP Exterior Gateway Protocol
A protocol which distributes routing information to the
gateways (routers) which connect autonomous systems.
A network standard for the hardware and data link levels.
There are two types of Ethernet: Digital/Intel/Xerox (DIX)
and IEEE 802.3.
FDDI Fiber Distributed Data Interface
FDDI is a high-speed (100Mb) token ring LAN.
FIPS Federal Information Processing Standard
FTP File Transfer Protocol
The Internet standard high-level protocol for
transferring files from one computer to another.
gateway See router
A unit of data storage size which represents 2^30 (over
1 billion) characters of information.
2^30 bits of information (usually used to express a
data transfer rate; as in, 1 gigabit/second = 1Gbps).
GNU Gnu's Not UNIX
A UNIX-compatible operating system developed by the
Free Software Foundation.
header The portion of a packet, preceding the actual data,
containing source and destination addresses and
The part of an internet address that designates which
node on the (sub)network is being addressed.
High-speed communications link.
IAB Internet Activities Board
The IAB is the coordinating committee for Internet
design, engineering and management.
IBM International Business Machines Corporation
ICMP Internet Control Message Protocol
ICMP is an extension to the Internet Protocol. It
allows for the generation of error messages,
test packets and informational messages related to IP.
IEEE Institute for Electrical and Electronics Engineers
IETF Internet Engineering Task Force
The IETF is a large open community of network designers,
operators, vendors, and researchers whose purpose is to
coordinate the operation, management and evolution of
the Internet, and to resolve short- and mid-range
protocol and architectural issues. It is a major source
of proposed protocol standards which are submitted to the
Internet Activities Board for final approval. The IETF
meets three times a year and extensive minutes of the
plenary proceedings are issued.
Any connection of two or more local or wide-area networks.
The global collection of interconnected local, mid-level and
wide-area networks which use IP as the network layer
An assigned number which identifies a host in an internet.
It has two or three parts: network number, optional subnet
number, and host number.
IP Internet Protocol
The network layer protocol for the Internet. It is a packet
switching, datagram protocol defined in RFC 791.
IRTF Internet Research Task Force
The IRTF is a community of network researchers,
generally with an Internet focus. The work of the IRTF
is governed by its Internet Research Steering Group (IRSG).
ISO International Organization for Standardization
A unit of data storage size which represents 2^10
(1024) characters of information.
2^10 bits of information (usually used to express a
data transfer rate; as in, 1 kilobit/second = 1Kbps = 1Kb).
LAN Local Area Network
A network that takes advantage of the proximity of computers
to offer relatively efficient, higher speed communications
than long-haul or wide-area networks.
LISP List Processing Language
A high-level computer language invented by Professor John
McCarthy in 1961 to support research into computer based
logic, logical reasoning, and artificial intelligence. It
was the first symbolic (as opposed to numeric) computer
MAC Medium Access Control
For broadcast networks, it is the method which devices use
to determine which device has line access at any given
Mac Apple Macintosh computer.
MAN Metropolitan Area Network
A unit of data storage size which represents over
2^20 (one million) characters of information.
2^20 bits of information (usually used to express a
data transfer rate; as in, 1 megabit/second = 1Mbps).
MILNET Military Network
A network used for unclassified military production
applications. It is part of the DDN and the Internet.
MIT Massachusetts Institute of Technology
MTTF Mean Time to Failure
The average time between hardware breakdown or loss of
service. This may be an empirical measurement or a
calculation based on the MTTF of component parts.
MTTR Mean Time to Recovery (or Repair)
The average time it takes to restore service after a
breakdown or loss. This is usually an empirical measurement.
MVS Multiple Virtual Storage
An IBM operating system based on OS/1.
NASA National Aeronautics and Space Administration
NBS National Bureau of Standards
Now called NIST.
The part of an internet address which designates the
network to which the addressed node belongs.
NFS Network File System
A network service that lets a program running on one
computer to use data stored on a different computer on
the same internet as if it were on its own disk.
NIC Network Information Center
An organization which provides network users with
information about services provided by the network.
NOC Network Operations Center
An organization that is responsible for maintaining
NIST National Institute of Standards and Technology
NSF National Science Foundation
NSFNET National Science Foundation Network
The NSFNET is a highspeed "network of networks" which is
hierarchical in nature. At the highest level is a network
that spans the continental United States. Attached to that
are mid-level networks and attached to the mid-levels are
campus and local networks. NSFNET also has connections out
of the U.S. to Canada, Mexico, Europe, and the Pacific Rim.
The NSFNET is part of the Internet.
NSFNET Mid-level Level Network
A network connected to the highest level of the NSFNET that
covers a region of the United States. It is to mid-level
networks that local sites connect. The mid-level networks
were once called "regionals".
OSI Open Systems Interconnection
A set of protocols designed to be an international standard
method for connecting unlike computers and networks. Europe
has done most of the work developing OSI and will probably
use it as soon as possible.
OSI Reference Model
An "outline" of OSI which defines its seven layers and
their functions. Sometimes used to help describe other
OSPF Open Shortest-Path First Interior Gateway Protocol
A proposed replacement for RIP. It addresses some
problems of RIP and is based upon principles that have
been well-tested in non-internet protocols. Originally
acronymed as OSPFIGP.
packet The unit of data sent across a packet switching network.
The term is used loosely. While some Internet
literature uses it to refer specifically to data sent
across a physical network, other literature views
the Internet as a packet switching network
and describes IP datagrams as packets.
PC Personal Computer
PCNFS Personal Computer Network File System
POSIX Portable Operating System Interface
Operating system based on UNIX.
PPP Point-to-Point Protocol
The Point-to-Point Protocol (PPP) provides a method for
transmitting datagrams over serial point-to-point links.
A formal description of message formats and the rules
two computers must follow to exchange those messages.
Protocols can describe low-level details of
machine-to-machine interfaces (e.g., the order in
which bits and bytes are sent across a wire)
or high-level exchanges between allocation
programs (e.g., the way in which two programs
transfer a file across the Internet).
RFC The Internet's Request for Comments documents series
The RFCs are working notes of the Internet research and
development community. A document in this series may be on
essentially any topic related to computer communication, and
may be anything from a meeting report to the specification of
RIP Routing Interchange Protocol
One protocol which may be used on internets simply to pass
routing information between gateways. It is used on may
LANs and on some of the NSFNET intermediate level networks.
RJE Remote Job Entry
The general protocol for submitting batch jobs and
retrieving the results.
RLOGIN Remote Login
A service on internets very similar to TELNET. RLOGIN was
invented for use between Berkeley Unix systems on the same
LAN at a time when TELNET programs didn't provide all the
services users wanted. Berkeley plans to phase it out.
router A special-purpose dedicated computer that attaches to
two or more networks and routes packets from one
network to the other. In particular, an Internet
gateway routes IP datagrams among the networks it
connects. Gateways route packets to other
gateways until they can be delivered to the final
destination directly across one physical network.
RPC Remote Procedure Call
An easy and popular paradigm for implementing the
client-server model of distributed computing.
server A computer that shares its resources, such as printers
and files, with other computers on the network. An
example of this is a Network Files System (NFS)
Server which shares its disk space with one or more
workstations that may not have local disk drives of
SLIP Serial Line Internet Protocol
SLIP is currently a defacto standard, commonly used for
point-to-point serial connections running TCP/IP. It is
not an Internet standard but is defined in RFC 1055.
SMTP Simple Mail Transfer Protocol
The Internet standard protocol for transferring
electronic mail messages from one computer to another.
SMTP specifies how two mail systems interact and the
format of control messages they exchange to transfer mail.
SNA System Network Architecture
IBM's data communications protocol.
SNMP Simple Network Management Protocol
The Simple Network Management Protocol (RFC 1157) is the
Internet's standard for remote monitoring and management
of hosts, routers and other nodes and devices on a network.
subnet A portion of a network, which may be a physically independent
network, which shares a network address with other portions
of the network and is distinguished by a subnet number. A
subnet is to a network what a network is to an internet.
A part of the internet address which designates a subnet.
It is ignored for the purposes internet routing, but is
used for intranet routing.
T1 A term for a digital carrier facility used to transmit a
DS-1 formatted digital signal at 1.544 megabits per second.
T3 A term for a digital carrier facility used to transmit a DS-3
formatted digital signal at 44.746 megabits per second.
TCP Transmission Control Protocol
A transport layer protocol for the Internet. It is a
connection oriented, stream protocol defined by RFC 793.
TCP/IP Transmission Control Protocol/Internet Protocol
This is a common shorthand which refers to the suite
of application and transport protocols which run over IP.
These include FTP, TELNET, SMTP, and UDP (a transport
Telenet A public packet-switching network operated by US Sprint.
Also known as "SprintNet".
TELNET The Internet standard protocol for remote terminal
connection service. TELNET allows a user at one site
to interact with a remote timesharing system at
another site as if the user's terminal was connected
directly to the remote computer.
THEnet The Texas Higher Education Network, a multiprotocol
network connecting most major academic and research
institutions in the State of Texas, as well as several
institutions in Mexico.
A type of LAN. Examples are IEEE 802.5, ProNET-10/80 and
FDDI. The term "token ring" is often used to denote 802.5
Tymnet A public character-switching/packet-switching network
operated by British Telecom.
UDP User Datagram Protocol
A transport layer protocol for the Internet. It is a
datagram protocol which adds a level of reliability and
multiplexing to IP datagrams. It is defined in RFC 768.
ULTRIX UNIX-based operating system for Digital Equipment Corporation
UNIX An operating system developed by Bell Laboratories that
supports multiuser and multitasking operations.
UUCP UNIX-to-UNIX Copy Program
A protocol used for communication between consenting
VMS Virtual Memory System
A Digital Equipment Corporation operating system.
WAN Wide Area Network
WHOIS An Internet program which allows users to query a database of
people and other Internet entities, such as domains,
networks, and hosts, kept at the NIC. The information for
people shows a person's company name, address, phone number
and email address.
XNS Xerox Network System
A data communications protocol suite developed by Xerox. It
uses Ethernet to move the data between computers.
X.25 A data communications interface specification developed to
describe how data passes into and out of public data
communications networks. The public networks such as
Sprintnet and Tymnet use X.25 to interface to customer
14. Security Considerations
Security issues are not discussed in this memo.
15. Authors' Addresses
Gary Scott Malkin
FTP Software, Inc.
26 Princess Street
Wakefield, MA 01880
Phone: (617) 246-0900
April N. Marine
Network Information Systems Center
333 Ravenswood Avenue, EJ294
Menlo Park, CA 94025
Phone: (415) 859-5318