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 1034 and 1035. 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 [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: 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
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 904. 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 959. 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 , 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