1. Glossary
10BaseT
A variant of Ethernet which allows stations to be attached via
twisted pair cable. See also: Ethernet, twisted pair.
802.x
The set of IEEE standards for the definition of LAN protocols.
See also: IEEE.
822
See: RFC 822std11(-> 2822prop)
:-)
This odd symbol is one of the ways a person can portray "mood" in
the very flat medium of computers--by using "smiley faces". This
is "metacommunication", and there are literally hundreds of such
symbols, from the obvious to the obscure. This particular example
expresses "happiness". Don't see it? Tilt your head to the left
90 degrees. Smiles are also used to denote sarcasm.
[Source: ZEN]
abstract syntax
A description of a data structure that is independent of machine-
oriented structures and encodings.
[Source: RFC1208]
Abstract Syntax Notation One (ASN.1)
The language used by the OSI protocols for describing abstract
syntax. This language is also used to encode SNMP packets. ASN.1
is defined in ISO documents 8824.2 and 8825.2. See also: Basic
Encoding Rules.
Acceptable Use Policy (AUP)
Many transit networks have policies which restrict the use to
which the network may be put. A well known example is NSFNET's
AUP which does not allow commercial use. Enforcement of AUPs
varies with the network. See also: National Science Foundation.
Access Control List (ACL)
Most network security systems operate by allowing selective use of
services. An Access Control List is the usual means by which
access to, and denial of, services is controlled. It is simply a
list of the services available, each with a list of the hosts
permitted to use the service.
ACK
See: Acknowledgment
acknowledgment (ACK)
A type of message sent to indicate that a block of data arrived at
its destination without error. See also: Negative
Acknowledgement.
[Source: NNSC]
ACL
See: Access Control List
AD
See: Administrative Domain
address
There are three types of addresses in common use within the
Internet. They are email address; IP, internet or Internet
address; and hardware or MAC address. See also: email address, IP
address, internet address, MAC address.
address mask
A bit mask used to identify which bits in an IP address correspond
to the network and subnet portions of the address. This mask is
often referred to as the subnet mask because the network portion
of the address can be determined by the encoding inherent in an IP
address.
address resolution
Conversion of an internet address into the corresponding physical
address.
Address Resolution Protocol (ARP)
Used to dynamically discover the low level physical network
hardware address that corresponds to the high level IP address for
a given host. ARP is limited to physical network systems that
support broadcast packets that can be heard by all hosts on the
network. It is defined in RFC 826std37. See also: proxy ARP.
Administrative Domain (AD)
A collection of hosts and routers, and the interconnecting
network(s), managed by a single administrative authority.
Advanced Research Projects Agency Network (ARPANET)
A pioneering longhaul network funded by ARPA (now DARPA). 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. See also: Defense Advanced
Research Projects Agency.
[Source: FYI4]
agent
In the client-server model, the part of the system that performs
information preparation and exchange on behalf of a client or
server application.
[Source: RFC1208]
alias
A name, usually short and easy to remember, that is translated
into another name, usually long and difficult to remember.
American National Standards Institute (ANSI)
This organization is responsible for approving U.S. standards in
many areas, including computers and communications. Standards
approved by this organization are often called ANSI standards
(e.g., ANSI C is the version of the C language approved by ANSI).
ANSI is a member of ISO. See also: International Organization for
Standardization.
[Source: NNSC]
American Standard Code for Information Interchange (ASCII)
A standard character-to-number encoding widely used in the
computer industry. See also: EBCDIC.
anonymous FTP
Anonymous FTP allows a user to retrieve documents, files,
programs, and other archived data from anywhere in the Internet
without having to establish a userid and password. By using the
special userid of "anonymous" the network user will bypass local
security checks and will have access to publicly accessible files
on the remote system. See also: archive site, File Transfer
Protocol.
ANSI
See: American National Standards Institute
API
See: Application Program Interface
Appletalk
A networking protocol developed by Apple Computer for
communication between Apple Computer products and other computers.
This protocol is independent of the network layer on which it is
run. Current implementations exist for Localtalk, a 235Kb/s local
area network; and Ethertalk, a 10Mb/s local area network.
[Source: NNSC]
application
A program that performs a function directly for a user. FTP, mail
and Telnet clients are examples of network applications.
application layer
The top layer of the network protocol stack. The application
layer is concerned with the semantics of work (e.g., formatting
electronic mail messages). How to represent that data and how to
reach the foreign node are issues for lower layers of the network.
[Source: MALAMUD]
Application Program Interface (API)
A set of calling conventions which define how a service is invoked
through a software package.
[Source: RFC1208]
archie
A system to automatically gather, index and serve information on
the Internet. The initial implementation of archie provided an
indexed directory of filenames from all anonymous FTP archives on
the Internet. Later versions provide other collections of
information. See also: archive site, Gopher, Prospero, Wide Area
Information Servers.
archive site
A machine that provides access to a collection of files across the
Internet. An "anonymous FTP archive site", for example, provides
access to this material via the FTP protocol. See also: anonymous
FTP, archie, Gopher, Prospero, Wide Area Information Servers.
ARP
See: Address Resolution Protocol
ARPA
See: Defense Advanced Research Projects Agency
ARPANET
See: Advanced Research Projects Agency Network
AS
See: Autonomous System
ASCII
See: American Standard Code for Information Interchange
ASN.1
See: Abstract Syntax Notation One
assigned numbers
The RFC [STD2] which documents the currently assigned values from
several series of numbers used in network protocol
implementations. This RFC is updated periodically and, in any
case, current information can be obtained from the Internet
Assigned Numbers Authority (IANA). If you are developing a
protocol or application that will require the use of a link,
socket, port, protocol, etc., please contact the IANA to receive a
number assignment. See also: Internet Assigned Numbers Authority,
STD.
[Source: STD2]
Asynchronous Transfer Mode (ATM)
A method for the dynamic allocation of bandwidth using a fixed-
size packet (called a cell). ATM is also known as "fast packet".
ATM
See: Asynchronous Transfer Mode
AUP
See: Acceptable Use Policy
authentication
The verification of the identity of a person or process.
[Source: MALAMUD]
Autonomous System (AS)
A collection of routers under a single administrative authority
using a common Interior Gateway Protocol for routing packets.
backbone
The top level in a hierarchical network. Stub and transit
networks which connect to the same backbone are guaranteed to be
interconnected. See also: stub network, transit network.
bandwidth
Technically, the difference, in Hertz (Hz), between the highest
and lowest frequencies of a transmission channel. However, as
typically used, the amount of data that can be sent through a
given communications circuit.
bang path
A series of machine names used to direct electronic mail from one
user to another, typically by specifying an explicit UUCP path
through which the mail is to be routed. See also: email address,
mail path, UNIX-to-UNIX CoPy.
baseband
A transmission medium through which digital signals are sent
without complicated frequency shifting. In general, only one
communication channel is available at any given time. Ethernet is
an example of a baseband network. See also: broadband, Ethernet.
[Source: NNSC]
Basic Encoding Rules (BER)
Standard rules for encoding data units described in ASN.1.
Sometimes incorrectly lumped under the term ASN.1, which properly
refers only to the abstract syntax description language, not the
encoding technique. See also: Abstract Syntax Notation One.
[Source: NNSC]
BBS
See: Bulletin Board System
BCNU
Be Seein' You
BER
See: Basic Encoding Rules
Berkeley Internet Name Domain (BIND)
Implementation of a DNS server developed and distributed by the
University of California at Berkeley. Many Internet hosts run
BIND, and it is the ancestor of many commercial BIND
implementations.
Berkeley Software Distribution (BSD)
Implementation of the UNIX operating system and its utilities
developed and distributed by the University of California at
Berkeley. "BSD" is usually preceded by the version number of the
distribution, e.g., "4.3 BSD" is version 4.3 of the Berkeley UNIX
distribution. Many Internet hosts run BSD software, and it is the
ancestor of many commercial UNIX implementations.
[Source: NNSC]
BGP
See: Border Gateway Protocol
big-endian
A format for storage or transmission of binary data in which the
most significant bit (or byte) comes first. The term comes from
"Gulliver's Travels" by Jonathan Swift. The Lilliputians, being
very small, had correspondingly small political problems. The
Big-Endian and Little-Endian parties debated over whether soft-
boiled eggs should be opened at the big end or the little end.
See also: little-endian.
[Source: RFC1208]
binary
11001001
BIND
See: Berkeley Internet Name Domain
Birds Of a Feather (BOF)
A Birds Of a Feather (flocking together) is an informal discussion
group. It is formed, often ad hoc, to consider a specific issue
and, therefore, has a narrow focus.
Bitnet
An academic computer network that provides interactive electronic
mail and file transfer services, using a store-and-forward
protocol, based on IBM Network Job Entry protocols. Bitnet-II
encapsulates the Bitnet protocol within IP packets and depends on
the Internet to route them.
BOF
See: Birds Of a Feather
BOOTP
The Bootstrap Protocol, described in RFCs 951draft and 1084(-> 1533(-> 2132draft) | 1497(-> 1533(-> 2132draft)) | 1395(-> 1533(-> 2132draft) | 1497(-> 1533(-> 2132draft)))), is used
for booting diskless nodes. See also: Reverse Address Resolution
Protocol.
Border Gateway Protocol (BGP)
The Border Gateway Protocol is an exterior gateway protocol
defined in RFCs 1267hist and 1268hist(-> 1655(-> 1772draft)). It's design is based on experience
gained with EGP, as defined in STD 18, RFC 904hist, and EGP usage in
the NSFNET Backbone, as described in RFCs 1092 and 1093. See
also: Exterior Gateway Protocol.
bounce
The return of a piece of mail because of an error in its delivery.
[Source: ZEN]
bridge
A device which forwards traffic between network segments based on
datalink layer information. These segments would have a common
network layer address. See also: gateway, router.
broadband
A transmission medium capable of supporting a wide range of
frequencies. It can carry multiple signals by dividing the total
capacity of the medium into multiple, independent bandwidth
channels, where each channel operates only on a specific range of
frequencies. See also: baseband.
broadcast
A special type of multicast packet which all nodes on the network
are always willing to receive. See also: multicast.
broadcast storm
An incorrect packet broadcast onto a network that causes multiple
hosts to respond all at once, typically with equally incorrect
packets which causes the storm to grow exponentially in severity.
brouter
A device which bridges some packets (i.e., forwards based on
datalink layer information) and routes other packets (i.e.,
forwards based on network layer information). The bridge/route
decision is based on configuration information. See also: bridge,
router.
BSD
See: Berkeley Software Distribution
BTW
By The Way
Bulletin Board System (BBS)
A computer, and associated software, which typically provides
electronic messaging services, archives of files, and any other
services or activities of interest to the bulletin board system's
operator. Although BBS's have traditionally been the domain of
hobbyists, an increasing number of BBS's are connected directly to
the Internet, and many BBS's are currently operated by government,
educational, and research institutions. See also: Electronic
Mail, Internet, Usenet.
[Source: NWNET]
Campus Wide Information System (CWIS)
A CWIS makes information and services publicly available on campus
via kiosks, and makes interactive computing available via kiosks,
interactive computing systems and campus networks. Services
routinely include directory information, calendars, bulletin
boards, databases.
CCIRN
See: Coordinating Committee for Intercontinental Research Networks
CCITT
See: Comite Consultatif International de Telegraphique et
Telephonique
CERT
See: Computer Emergency Response Team
checksum
A computed value which is dependent upon the contents of a packet.
This value is sent along with the packet when it is transmitted.
The receiving system computes a new checksum based upon the
received data and compares this value with the one sent with the
packet. If the two values are the same, the receiver has a high
degree of confidence that the data was received correctly.
[Source: NNSC]
circuit switching
A communications paradigm in which a dedicated communication path
is established between two hosts, and on which all packets travel.
The telephone system is an example of a circuit switched network.
See also: connection-oriented, connectionless, packet switching.
client
A computer system or process that requests a service of another
computer system or process. A workstation requesting the contents
of a file from a file server is a client of the file server. See
also: client-server model, server.
[Source: NNSC]
client-server model
A common way to describe the paradigm of many network protocols.
Examples include the name-server/name-resolver relationship in DNS
and the file-server/file-client relationship in NFS. See also:
client, server, Domain Name System, Network File System.
CNI
See: Coalition for Networked Information
Coalition for Networked Information (CNI)
A consortium formed by American Research Libraries, CAUSE, and
EDUCOM to promote the creation of, and access to, information
resources in networked environments in order to enrich scholarship
and enhance intellectual productivity.
Comite Consultatif International de Telegraphique et Telephonique
(CCITT)
This organization is part of the United National International
Telecommunications Union (ITU) and is responsible for making
technical recommendations about telephone and data communications
systems. Every four years CCITT holds plenary sessions where they
adopt new standards; the most recent was in 1992.
[Source: NNSC]
Computer Emergency Response Team (CERT)
The CERT was formed by DARPA in November 1988 in response to the
needs exhibited during the Internet worm incident. The CERT
charter is to work with the Internet community to facilitate its
response to computer security events involving Internet hosts, to
take proactive steps to raise the community's awareness of
computer security issues, and to conduct research targeted at
improving the security of existing systems. CERT products and
services include 24-hour technical assistance for responding to
computer security incidents, product vulnerability assistance,
technical documents, and tutorials. In addition, the team
maintains a number of mailing lists (including one for CERT
Advisories), and provides an anonymous FTP server, at "cert.org",
where security-related documents and tools are archived. The CERT
may be reached by email at "cert@cert.org" and by telephone at
+1-412-268-7090 (24-hour hotline). See also: Defense Advanced
Research Projects Agency, worm.
congestion
Congestion occurs when the offered load exceeds the capacity of a
data communication path.
connection-oriented
The data communication method in which communication proceeds
through three well-defined phases: connection establishment, data
transfer, connection release. TCP is a connection-oriented
protocol. See also: circuit switching, connectionless, packet
switching, Transmission Control Protocol.
connectionless
The data communication method in which communication occurs
between hosts with no previous setup. Packets between two hosts
may take different routes, as each is independent of the other.
UDP is a connectionless protocol. See also: circuit switching,
connection-oriented, packet switching, User Datagram Protocol.
Coordinating Committee for Intercontinental Research Networks (CCIRN)
A committee that includes the United States FNC and its
counterparts in North America and Europe. Co-chaired by the
executive directors of the FNC and the European Association of
Research Networks (RARE), the CCIRN provides a forum for
cooperative planning among the principal North American and
European research networking bodies. See also: Federal Networking
Council, RARE.
[Source: MALAMUD]
core gateway
Historically, one of a set of gateways (routers) operated by the
Internet Network Operations Center at Bolt, Beranek and Newman
(BBN). The core gateway system formed a central part of Internet
routing in that all groups must advertise paths to their networks
from a core gateway.
[Source: MALAMUD]
Corporation for Research and Educational Networking (CREN)
This organization was formed in October 1989, when Bitnet and
CSNET (Computer + Science NETwork) were combined under one
administrative authority. CSNET is no longer operational, but
CREN still runs Bitnet. See also: Bitnet.
[Source: NNSC]
cracker
A cracker is an individual who attempts to access computer systems
without authorization. These individuals are often malicious, as
opposed to hackers, and have many means at their disposal for
breaking into a system. See also: hacker, Computer Emergency
Response Team, Trojan Horse, virus, worm.
CRC
See: cyclic redundancy check
CREN
See: Corporation for Research and Educational Networking
CWIS
See: Campus Wide Information system
Cyberspace
A term coined by William Gibson in his fantasy novel Neuromancer
to describe the "world" of computers, and the society that gathers
around them.
[Source: ZEN]
Cyclic Redundancy Check (CRC)
A number derived from a set of data that will be transmitted. By
recalculating the CRC at the remote end and comparing it to the
value originally transmitted, the receiving node can detect some
types of transmission errors.
[Source: MALAMUD]
DARPA
See: Defense Advanced Research Projects Agency
Data Encryption Key (DEK)
Used for the encryption of message text and for the computation of
message integrity checks (signatures). See also: encryption.
Data Encryption Standard (DES)
A popular, standard encryption scheme. See also: encryption.
datagram
A self-contained, independent entity of data carrying sufficient
information to be routed from the source to the destination
computer without reliance on earlier exchanges between this source
and destination computer and the transporting network. See also:
frame, packet.
[Source: J. Postel]
DCA
See: Defense Information Systems Agency
DCE
Data Circuit-terminating Equipment
DCE
See: Distributed Computing Environment
DDN
See: Defense Data Network
DDN NIC
See: Defense Data Network Network Information Center
DECnet
A proprietary network protocol designed by Digital Equipment
Corporation. The functionality of each Phase of the
implementation, such as Phase IV and Phase V, is different.
default route
A routing table entry which is used to direct packets addressed to
networks not explicitly listed in the routing table.
[Source: MALAMUD]
Defense Advanced Research Projects Agency (DARPA)
An agency of the U.S. Department of Defense responsible for the
development of new technology for use by the military. DARPA
(formerly known as ARPA) was responsible for funding much of the
development of the Internet we know today, including the Berkeley
version of Unix and TCP/IP.
[Source: NNSC]
Defense Data Network (DDN)
A global communications network serving the US Department of
Defense composed of MILNET, other portions of the Internet, and
classified networks which are not part of the Internet. The DDN
is used to connect military installations and is managed by the
Defense Information Systems Agency. See also: Defense Information
Systems Agency.
Defense Data Network Network Information Center (DDN NIC)
Often called "The NIC", the DDN NIC's primary responsibility is
the assignment of Internet network addresses and Autonomous System
numbers, the administration of the root domain, and providing
information and support services to the DDN. It is also a primary
repository for RFCs. See also: Autonomous System, network
address, Internet Registry, Network Information Center, Request
For Comments.
Defense Information Systems Agency (DISA)
Formerly called the Defense Communications Agency (DCA), this is
the government agency responsible for managing the DDN portion of
the Internet, including the MILNET. Currently, DISA administers
the DDN, and supports the user assistance services of the DDN NIC.
See also: Defense Data Network.
DEK
See: Data Encryption Key
DES
See: Data Encryption Standard
dialup
A temporary, as opposed to dedicated, connection between machines
established over a standard phone line.
Directory Access Protocol
X.500 protocol used for communication between a Directory User
Agent and a Directory System Agent.
[Source: MALAMUD]
Directory System Agent (DSA)
The software that provides the X.500 Directory Service for a
portion of the directory information base. Generally, each DSA is
responsible for the directory information for a single
organization or organizational unit.
[Source: RFC1208]
Directory User Agent (DUA)
The software that accesses the X.500 Directory Service on behalf
of the directory user. The directory user may be a person or
another software element.
[Source: RFC1208]
DISA
See: Defense Information Systems Agency
Distributed Computing Environment (DCE)
An architecture of standard programming interfaces, conventions,
and server functionalities (e.g., naming, distributed file system,
remote procedure call) for distributing applications transparently
across networks of heterogeneous computers. Promoted and
controlled by the Open Software Foundation (OSF), a consortium led
by Digital, IBM and Hewlett Packard.
[Source: RFC1208]
distributed database
A collection of several different data repositories that looks
like a single database to the user. A prime example in the
Internet is the Domain Name System.
DIX Ethernet
See: Ethernet
DNS
See: Domain Name System
domain
"Domain" is a heavily overused term in the Internet. It can be
used in the Administrative Domain context, or the Domain Name
context. See also: Administrative Domain, Domain Name System.
Domain Name System (DNS)
The DNS is a general purpose distributed, replicated, data query
service. The principal use is the lookup of host IP addresses
based on host names. The style of host names now used in the
Internet is called "domain name", because they are the style of
names used to look up anything in the DNS. Some important domains
are: .COM (commercial), .EDU (educational), .NET (network
operations), .GOV (U.S. government), and .MIL (U.S. military).
Most countries also have a domain. For example, .US (United
States), .UK (United Kingdom), .AU (Australia). It is defined in
STD 13, RFCs 1034std13 and 1035std13. See also: Fully Qualified Domain
Name.
dot address (dotted decimal notation)
Dot address refers to the common notation for IP addresses of the
form A.B.C.D; where each letter represents, in decimal, one byte
of a four byte IP address. See also: IP address.
[Source: FYI4]
DS1
A framing specification for T-1 synchronous lines. See also: T1
DS3
A framing specification for T-3 synchronous lines. See also: T3
DSA
See: Directory System Agent
DTE
Data Terminal Equipment
DUA
See: Directory User Agent
dynamic adaptive routing
Automatic rerouting of traffic based on a sensing and analysis of
current actual network conditions. NOTE: this does not include
cases of routing decisions taken on predefined information.
[Source: J. Postel]
EARN
See: European Academic and Research Network
EBCDIC
See: Extended Binary Coded Decimal Interchange Code
Ebone
A pan-European backbone service.
EFF
See: Electronic Frontier Foundation
EFLA
See: Extended Four Letter Acronym
EGP
See: Exterior Gateway Protocol
Electronic Frontier Foundation (EFF)
A foundation established to address social and legal issues
arising from the impact on society of the increasingly pervasive
use of computers as a means of communication and information
distribution.
Electronic Mail (email)
A system whereby a computer user can exchange messages with other
computer users (or groups of users) via a communications network.
Electronic mail is one of the most popular uses of the Internet.
[Source: NNSC]
email
See: Electronic mail
email address
The domain-based or UUCP address that is used to send electronic
mail to a specified destination. For example an editor's address
is "gmalkin@xylogics.com". See also: bang path, mail path, UNIX-
to-UNIX CoPy.
[Source: ZEN]
encapsulation
The technique used by layered protocols in which a layer adds
header information to the protocol data unit (PDU) from the layer
above. As an example, in Internet terminology, a packet would
contain a header from the physical layer, followed by a header
from the network layer (IP), followed by a header from the
transport layer (TCP), followed by the application protocol data.
[Source: RFC1208]
encryption
Encryption is the manipulation of a packet's data in order to
prevent any but the intended recipient from reading that data.
There are many types of data encryption, and they are the basis of
network security. See also: Data Encryption Standard.
Ethernet
A 10-Mb/s standard for LANs, initially developed by Xerox, and
later refined by Digital, Intel and Xerox (DIX). All hosts are
connected to a coaxial cable where they contend for network access
using a Carrier Sense Multiple Access with Collision Detection
(CSMA/CD) paradigm. See also: 802.x, Local Area Network, token
ring.
Ethernet meltdown
An event that causes saturation, or near saturation, on an
Ethernet. It usually results from illegal or misrouted packets
and typically lasts only a short time.
[Source: COMER]
European Academic and Research Network (EARN)
A network connecting European academic and research institutions
with electronic mail and file transfer services using the Bitnet
protocol. See also: Bitnet
Extended Binary Coded Decimal Interchange Code (EBCDIC)
A standard character-to-number encoding used primarily by IBM
computer systems. See also: ASCII.
Extended Four Letter Acronym (EFLA)
A recognition of the fact that there are far too many TLAs. See
also: Three Letter Acronym.
[Source: K. Morgan]
Exterior Gateway Protocol (EGP)
A protocol which distributes routing information to the routers
which connect autonomous systems. The term "gateway" is
historical, as "router" is currently the preferred term. There is
also a routing protocol called EGP defined in STD 18, RFC 904hist.
See also: Autonomous System, Border Gateway Protocol, Interior
Gateway Protocol.
eXternal Data Representation (XDR)
A standard for machine independent data structures developed by
Sun Microsystems and defined in RFC 1014. It is similar to ASN.1.
See also: Abstract Syntax Notation One.
[Source: RFC1208]
FARNET
A non-profit corporation, established in 1987, whose mission is to
advance the use of computer networks to improve research and
education.
FAQ
Frequently Asked Question
FDDI
See: Fiber Distributed Data Interface
Federal Information Exchange (FIX)
One of the connection points between the American governmental
internets and the Internet.
[Source: SURA]
Federal Networking Council (FNC)
The coordinating group of representatives from those federal
agencies involved in the development and use of federal
networking, especially those networks using TCP/IP and the
Internet. Current members include representatives from DOD, DOE,
DARPA, NSF, NASA, and HHS. See also: Defense Advanced Research
Projects Agency, National Science Foundation.
Fiber Distributed Data Interface (FDDI)
A high-speed (100Mb/s) LAN standard. The underlying medium is
fiber optics, and the topology is a dual-attached, counter-
rotating token ring. See also: Local Area Network, token ring.
[Source: RFC1208]
file transfer
The copying of a file from one computer to another over a computer
network. See also: File Transfer Protocol, Kermit.
File Transfer Protocol (FTP)
A protocol which allows a user on one host to access, and transfer
files to and from, another host over a network. Also, FTP is
usually the name of the program the user invokes to execute the
protocol. It is defined in STD 9, RFC 959std9. See also: anonymous
FTP.
finger
A program that displays information about a particular user, or
all users, logged on the local system or on a remote system. It
typically shows full name, last login time, idle time, terminal
line, and terminal location (where applicable). It may also
display plan and project files left by the user.
FIX
See: Federal Information Exchange
flame
A strong opinion and/or criticism of something, usually as a frank
inflammatory statement, in an electronic mail message. It is
common to precede a flame with an indication of pending fire
(i.e., FLAME ON!). Flame Wars occur when people start flaming
other people for flaming when they shouldn't have. See also:
Electronic Mail
FNC
See: Federal Networking Council
For Your Information (FYI)
A subseries of RFCs that are not technical standards or
descriptions of protocols. FYIs convey general information about
topics related to TCP/IP or the Internet. See also: Request For
Comments, STD.
FQDN
See: Fully Qualified Domain Name
fragment
A piece of a packet. When a router is forwarding an IP packet to
a network that has a maximum packet size smaller than the packet
size, it is forced to break up that packet into multiple
fragments. These fragments will be reassembled by the IP layer at
the destination host.
fragmentation
The IP process in which a packet is broken into smaller pieces to
fit the requirements of a physical network over which the packet
must pass. See also: reassembly.
frame
A frame is a datalink layer "packet" which contains the header and
trailer information required by the physical medium. That is,
network layer packets are encapsulated to become frames. See
also: datagram, encapsulation, packet.
freenet
Community-based bulletin board system with email, information
services, interactive communications, and conferencing. Freenets
are funded and operated by individuals and volunteers -- in one
sense, like public television. They are part of the National
Public Telecomputing Network (NPTN), an organization based in
Cleveland, Ohio, devoted to making computer telecommunication and
networking services as freely available as public libraries.
[Source: LAQUEY]
FTP
See: File Transfer Protocol
Fully Qualified Domain Name (FQDN)
The FQDN is the full name of a system, rather than just its
hostname. For example, "venera" is a hostname and
"venera.isi.edu" is an FQDN. See also: hostname, Domain Name
System.
FYI
See: For Your Information
gross
A dozen dozen (144).
gated
Gatedaemon. A program which supports multiple routing protocols
and protocol families. It may be used for routing, and makes an
effective platform for routing protocol research. The software is
freely available by anonymous FTP from "gated.cornell.edu".
Pronounced "gate-dee". See also: Exterior Gateway Protocol, Open
Shortest Path First..., Routing Information Protocol, routed.
gateway
The term "router" is now used in place of the original definition
of "gateway". Currently, a gateway is a communications
device/program which passes data between networks having similar
functions but dissimilar implementations. This should not be
confused with a protocol converter. By this definition, a router
is a layer 3 (network layer) gateway, and a mail gateway is a
layer 7 (application layer) gateway. See also: mail gateway,
router, protocol converter.
Gopher
A distributed information service that makes available
hierarchical collections of information across the Internet.
Gopher uses a simple protocol that allows a single Gopher client
to access information from any accessible Gopher server, providing
the user with a single "Gopher space" of information. Public
domain versions of the client and server are available. See also:
archie, archive site, Prospero, Wide Area Information Servers.
GOSIP
See: Government OSI Profile
Government OSI Profile
A subset of OSI standards specific to U.S. Government
procurements, designed to maximize interoperability in areas where
plain OSI standards are ambiguous or allow excessive options.
[Source: BIG-LAN]
hacker
A person who delights in having an intimate understanding of the
internal workings of a system, computers and computer networks in
particular. The term is often misused in a pejorative context,
where "cracker" would be the correct term. See also: cracker.
header
The portion of a packet, preceding the actual data, containing
source and destination addresses, and error checking and other
fields. A header is also the part of an electronic mail message
that precedes the body of a message and contains, among other
things, the message originator, date and time. See also:
Electronic Mail, packet.
heterogeneous network
A network running multiple network layer protocols. See also:
DECnet, IP, IPX, XNS.
hierarchical routing
The complex problem of routing on large networks can be simplified
by reducing the size of the networks. This is accomplished by
breaking a network into a hierarchy of networks, where each level
is responsible for its own routing. The Internet has, basically,
three levels: the backbones, the mid-levels, and the stub
networks. The backbones know how to route between the mid-levels,
the mid-levels know how to route between the sites, and each site
(being an autonomous system) knows how to route internally. See
also: Autonomous System, Exterior Gateway Protocol, Interior
Gateway Protocol, stub network, transit network.
High Performance Computing and Communications (HPCC)
High performance computing encompasses advanced computing,
communications, and information technologies, including scientific
workstations, supercomputer systems, high speed networks, special
purpose and experimental systems, the new generation of large
scale parallel systems, and application and systems software with
all components well integrated and linked over a high speed
network.
[Source: HPCC]
High Performance Parallel Interface (HIPPI)
An emerging ANSI standard which extends the computer bus over
fairly short distances at speeds of 800 and 1600 Mb/s. HIPPI is
often used in a computer room to connect a supercomputer to
routers, frame buffers, mass-storage peripherals, and other
computers. See also: American National Standards Institute
[Source: MALAMUD]
HIPPI
See: High Performance Parallel Interface
hop
A term used in routing. A path to a destination on a network is a
series of hops, through routers, away from the origin.
host
A computer that allows users to communicate with other host
computers on a network. Individual users communicate by using
application programs, such as electronic mail, Telnet and FTP.
[Source: NNSC]
host address
See: internet address
hostname
The name given to a machine. See also: Fully Qualified Domain
Name.
[Source: ZEN]
host number
See: host address
HPCC
See: High Performance Computing and Communications
hub
A device connected to several other devices. In ARCnet, a hub is
used to connect several computers together. In a message handling
service, a hub is used for the transfer of messages across the
network.
[Source: MALAMUD]
I-D
See: Internet-Draft
IAB
See: Internet Architecture Board
IANA
See: Internet Assigned Numbers Authority
ICMP
See: Internet Control Message Protocol
IEEE
Institute of Electrical and Electronics Engineers
IEEE 802
See: 802.x
IEN
See: Internet Experiment Note
IESG
See: Internet Engineering Steering Group
IETF
See: Internet Engineering Task Force
IINREN
See: Interagency Interim National Research and Education Network
IGP
See: Interior Gateway Protocol
IMHO
In My Humble Opinion
IMR
See: Internet Monthly Report
Integrated Services Digital Network (ISDN)
An emerging technology which is beginning to be offered by the
telephone carriers of the world. ISDN combines voice and digital
network services in a single medium, making it possible to offer
customers digital data services as well as voice connections
through a single "wire". The standards that define ISDN are
specified by CCITT. See also: CCITT.
[Source: RFC1208]
Interagency Interim National Research and Education Network (IINREN)
An evolving operating network system. Near term (1992-1996)
research and development activities will provide for the smooth
evolution of this networking infrastructure into the future
gigabit NREN.
[Source: HPCC]
Interior Gateway Protocol (IGP)
A protocol which distributes routing information to the routers
within an autonomous system. The term "gateway" is historical, as
"router" is currently the preferred term. See also: Autonomous
System, Exterior Gateway Protocol, Open Shortest Path First...,
Routing Information Protocol.
Intermediate System (IS)
An OSI system which performs network layer forwarding. It is
analogous to an IP router. See also: Open Systems
Interconnection, router.
Intermediate System-Intermediate System (IS-IS)
The OSI IGP. See also: Open Systems Interconnection, Interior
Gateway Protocol.
International Organization for Standardization (ISO)
A voluntary, nontreaty organization founded in 1946 which is
responsible for creating international standards in many areas,
including computers and communications. Its members are the
national standards organizations of the 89 member countries,
including ANSI for the U.S. See also: American National Standards
Institute, Open Systems Interconnection.
[Source: TAN]
internet
While an internet is a network, the term "internet" is usually
used to refer to a collection of networks interconnected with
routers. See also: network.
Internet
(note the capital "I") The Internet is the largest internet in the
world. Is a three level hierarchy composed of backbone networks
(e.g., NSFNET, MILNET), mid-level networks, and stub networks.
The Internet is a multiprotocol internet. See also: backbone,
mid-level network, stub network, transit network, Internet
Protocol, Corporation for Research and Educational Networks,
National Science Foundation.
internet address
A IP address that uniquely identifies a node on an internet. An
Internet address (capital "I"), uniquely identifies a node on the
Internet. See also: internet, Internet, IP address.
Internet Architecture Board (IAB)
The technical body that oversees the development of the Internet
suite of protocols. It has two task forces: the IETF and the
IRTF. "IAB" previously stood for Internet Activities Board. See
also: Internet Engineering Task Force, Internet Research Task
Force.
Internet Assigned Numbers Authority (IANA)
The central registry for various Internet protocol parameters,
such as port, protocol and enterprise numbers, and options, codes
and types. The currently assigned values are listed in the
"Assigned Numbers" document [STD2]. To request a number
assignment, contact the IANA at "iana@isi.edu". See also:
assigned numbers, STD.
Internet Control Message Protocol (ICMP)
ICMP is an extension to the Internet Protocol. It allows for the
generation of error messages, test packets and informational
messages related to IP. It is defined in STD 5, RFC 792std5.
[Source: FYI4]
Internet-Draft (I-D)
Internet-Drafts are working documents of the IETF, its Areas, and
its Working Groups. As the name implies, Internet-Drafts are
draft documents. They are valid for a maximum of six months and
may be updated, replaced, or obsoleted by other documents at any
time. Very often, I-Ds are precursors to RFCs. See also:
Internet Engineering Task Force, Request For Comments.
Internet Engineering Steering Group (IESG)
The IESG is composed of the IETF Area Directors and the IETF
Chair. It provides the first technical review of Internet
standards and is responsible for day-to-day "management" of the
IETF. See also: Internet Engineering Task Force.
Internet Engineering Task Force (IETF)
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-range and mid-range protocol and architectural
issues. It is a major source of proposals for protocol standards
which are submitted to the IAB for final approval. The IETF meets
three times a year and extensive minutes are included in the IETF
Proceedings. See also: Internet, Internet Architecture Board.
[Source: FYI4]
Internet Experiment Note (IEN)
A series of reports pertinent to the Internet. IENs were
published in parallel to RFCs and are no longer active. See also:
Internet-Draft, Request For Comments.
Internet Monthly Report (IMR)
Published monthly, the purpose of the Internet Monthly Reports is
to communicate to the Internet Research Group the accomplishments,
milestones reached, or problems discovered by the participating
organizations.
internet number
See: internet address
Internet Protocol (IP)
The Internet Protocol, defined in STD 5, RFC 791std5, is the network
layer for the TCP/IP Protocol Suite. It is a connectionless,
best-effort packet switching protocol. See also: packet
switching, Request For Comments, TCP/IP Protocol Suite.
Internet Registry (IR)
The IANA has the discretionary authority to delegate portions of
its responsibility and, with respect to network address and
Autonomous System identifiers, has lodged this responsibility with
an IR. The IR function is performed by the DDN NIC. See also:
Autonomous System, network address, Defense Data Network...,
Internet Assigned Numbers Authority.
Internet Relay Chat (IRC)
A world-wide "party line" protocol that allows one to converse
with others in real time. IRC is structured as a network of
servers, each of which accepts connections from client programs,
one per user. See also: talk.
[Source: HACKER]
Internet Research Steering Group (IRSG)
The "governing body" of the IRTF. See also: Internet Research
Task Force.
[Source: MALAMUD]
Internet Research Task Force (IRTF)
The IRTF is chartered by the IAB to consider long-term Internet
issues from a theoretical point of view. It has Research Groups,
similar to IETF Working Groups, which are each tasked to discuss
different research topics. Multi-cast audio/video conferencing
and privacy enhanced mail are samples of IRTF output. See also:
Internet Architecture Board, Internet Engineering Task Force,
Privacy Enhanced Mail.
Internet Society (ISOC)
The Internet Society is a non-profit, professional membership
organization which facilitates and supports the technical
evolution of the Internet, stimulates interest in and educates the
scientific and academic communities, industry and the public about
the technology, uses and applications of the Internet, and
promotes the development of new applications for the system. The
Society provides a forum for discussion and collaboration in the
operation and use of the global Internet infrastructure. The
Internet Society publishes a quarterly newsletter, the Internet
Society News, and holds an annual conference, INET. The
development of Internet technical standards takes place under the
auspices of the Internet Society with substantial support from the
Corporation for National Research Initiatives under a cooperative
agreement with the US Federal Government.
[Source: V. Cerf]
Internetwork Packet eXchange (IPX)
Novell's protocol used by Netware. A router with IPX routing can
interconnect LANs so that Novell Netware clients and servers can
communicate. See also: Local Area Network.
interoperability
The ability of software and hardware on multiple machines from
multiple vendors to communicate meaningfully.
IP
See: Internet Protocol
IP address
The 32-bit address defined by the Internet Protocol in STD 5, RFC
