ISDN: See: Integrated Services Digital Network
ISO: See: International Organization for Standardization
ISO Development Environment (ISODE): Software that allows OSI services to use a TCP/IP network. Pronounced eye-so-dee-eee. See also: Open Systems Interconnection , TCP/IP Protocol Suite
ISOC: See: Internet Society
ISODE: See: ISO Development Environment
JKREY: Joyce K. Reynolds
KA9Q: A popular implementation of TCP/IP and associated protocols for amateur packet radio systems. See also: TCP/IP Protocol Suite [Source: RFC1208]
Kerberos: Kerberos is the security system of MIT's Project Athena. It is based on symmetric key cryptography. See also: encryption
Kermit: A popular file transfer protocol developed by Columbia University. Because Kermit runs in most operating environments, it provides an easy method of file transfer. Kermit is NOT the same as FTP. See also: File Transfer Protocol [Source: MALAMUD]
Knowbot: An experimental directory service. See also: white pages , WHOIS , X
LAN: See: Local Area Network
layer: Communication networks for computers may be organized as a set of more or less independent protocols, each in a different layer (also called level). The lowest layer governs direct host-to-host communication between the hardware at different hosts; the highest consists of user applications. Each layer builds on the layer beneath it. For each layer, programs at different hosts use protocols appropriate to the layer to communicate with each other. TCP/IP has five layers of protocols; OSI has seven. The advantages of different layers of protocols is that the methods of passing information from one layer to another are specified clearly as part of the protocol suite, and changes within a protocol layer are prevented from affecting the other layers. This greatly simplifies the task of designing and maintaining communication programs. See also: Open Systems Interconnection , TCP/IP Protocol Suite
listserv: An automated mailing list distribution system originally designed for the Bitnet/EARN network. See also: Bitnet , mailing list
little-endian: A format for storage or transmission of binary data in which the least significant byte (bit) comes first. See also: big-endian [Source: RFC1208]
LLC: See: Logical Link Control
Local Area Network (LAN): A data network intended to serve an area of only a few square kilometers or less. Because the network is known to cover only a small area, optimizations can be made in the network signal protocols that permit data rates up to 100Mb/s. See also: Ethernet , Fiber Distributed Data Interface , token ring , Wide Area Network [Source: NNSC]
Logical Link Control (LLC): The upper portion of the datalink layer, as defined in IEEE 802.2. The LLC sublayer presents a uniform interface to the user of the datalink service, usually the network layer. Beneath the LLC sublayer is the MAC sublayer. See also: x , layer , Media Access Control
Lurking: No active participation on the part of a subscriber to an mailing list or USENET newsgroup. A person who is lurking is just listening to the discussion. Lurking is encouraged for beginners who need to get up to speed on the history of the group. See also: Electronic Mail , mailing list , Usenet [Source: LAQUEY]
MAC: See: Media Access Control
MAC address: The hardware address of a device connected to a shared media. See also: Media Access Control , Ethernet , token ring [Source: MALAMUD]
mail bridge: A mail gateway that forwards electronic mail between two or more networks while ensuring that the messages it forwards meet certain administrative criteria. A mail bridge is simply a specialized form of mail gateway that enforces an administrative policy with regard to what mail it forwards. See also: Electronic Mail , mail gateway [Source: NNSC]
Mail Exchange Record (MX Record): A DNS resource record type indicating which host can handle mail for a particular domain. See also: Domain Name System , Electronic Mail [Source: MALAMUD]
mail exploder: Part of an electronic mail delivery system which allows a message to be delivered to a list of addresses. Mail exploders are used to implement mailing lists. Users send messages to a single address and the mail exploder takes care of delivery to the individual mailboxes in the list. See also: Electronic Mail , email address , mailing list [Source: RFC1208]
mail gateway: A machine that connects two or more electronic mail systems (including dissimilar mail systems) and transfers messages between them. Sometimes the mapping and translation can be quite complex, and it generally requires a store-and-forward scheme whereby the message is received from one system completely before it is transmitted to the next system, after suitable translations. See also: Electronic Mail [Source: RFC1208]
mail path: A series of machine names used to direct electronic mail from one user to another. This system of email addressing has been used primarily in UUCP networks which are trying to eliminate its use altogether. See also: bang path , email address , UNIX-to-UNIX CoPy
mail server: A software program that distributes files or information in response to requests sent via email. Internet examples include Almanac and netlib. Mail servers have also been used in Bitnet to provide FTP-like services. See also: Bitnet , Electronic Mail , FTP [Source: NWNET]
mailing list: A list of email addresses, used by a mail exploder, to forward messages to groups of people. Generally, a mailing list is used to discuss certain set of topics, and different mailing lists discuss different topics. A mailing list may be moderated. This means that messages sent to the list are actually sent to a moderator who determines whether or not to send the messages on to everyone else. Requests to subscribe to, or leave, a mailing list should ALWAYS be sent to the list's "-request" address (e.g., ietf-request@cnri.reston.va.us for the IETF mailing list). See also: Electronic Mail , mail exploder
MAN: See: Metropolitan Area Network
Management Information Base (MIB): The set of parameters an SNMP management station can query or set in the SNMP agent of a network device (e.g., router). Standard, minimal MIBs have been defined, and vendors often have Private enterprise MIBs. In theory, any SNMP manager can talk to any SNMP agent with a properly defined MIB. See also: client-server model , Simple Network Management Protocol [Source: BIG-LAN]
Martian: A humorous term applied to packets that turn up unexpectedly on the wrong network because of bogus routing entries. Also used as a name for a packet which has an altogether bogus (non-registered or ill-formed) internet address. [Source: RFC1208]
Maximum Transmission Unit (MTU): The largest frame length which may be sent on a physical medium. See also: fragmentation , frame
Media Access Control (MAC): The lower portion of the datalink layer. The MAC differs for various physical media. See also: MAC Address , Ethernet , Logical Link Control , token ring
message switching: See: packet switching
Metropolitan Area Network (MAN): A data network intended to serve an area approximating that of a large city. Such networks are being implemented by innovative techniques, such as running fiber cables through subway tunnels. A popular example of a MAN is SMDS. See also: Local Area Network , Switched Multimegabit Data Service , Wide Area Network [Source: NNSC]
MIB: See: Management Information Base
mid-level network: Mid-level networks (a.k.a. regionals) make up the second level of the Internet hierarchy. They are the transit networks which connect the stub networks to the backbone networks. See also: backbone , Internet , stub network , transit network
MIME: See: Multipurpose Internet Mail Extensions
moderator: A person, or small group of people, who manage moderated mailing lists and newsgroups. Moderators are responsible for determining which email submissions are passed on to list. See also: Electronic Mail , mailing list , Usenet
MTU: See: Maximum Transmission Unit
MUD: See: Multi-User Dungeon
multicast: A packet with a special destination address which multiple nodes on the network may be willing to receive. See also: broadcast
multihomed host: A host which has more than one connection to a network. The host may send and receive data over any of the links but will not route traffic for other nodes. See also: host , router [Source: MALAMUD]
Multipurpose Internet Mail Extensions (MIME): An extension to Internet email which provides the ability to transfer non-textual data, such as graphics, audio and fax. It is defined in RFC 1341. See also: Electronic Mail
Multi-User Dungeon (MUD): Adventure, role playing games, or simulations played on the Internet. Devotees call them "text-based virtual reality adventures". The games can feature fantasy combat, booby traps and magic. Players interact in real time and can change the "world" in the game as they play it. Most MUDs are based on the Telnet protocol. See also: Telnet [Source: LAQUEY]
MX Record: See: Mail Exchange Record
NAK: See: Negative Acknowledgment
name resolution: The process of mapping a name into its corresponding address. See also: Domain Name System [Source: RFC1208]
namespace: A commonly distributed set of names in which all names are unique. [Source: MALAMUD]
National Institute of Standards and Technology (NIST): United States governmental body that provides assistance in developing standards. Formerly the National Bureau of Standards. [Source: MALAMUD]
National Research and Education Network (NREN): The NREN is the realization of an interconnected gigabit computer network devoted to Hign Performance Computing and Communications. See also: IINREN [Source: HPCC]
National Science Foundation (NSF): A U.S. government agency whose purpose is to promote the advancement of science. NSF funds science researchers, scientific projects, and infrastructure to improve the quality of scientific research. The NSFNET, funded by NSF, is an essential part of academic and research communications. It is a highspeed "network of networks" which is hierarchical in nature. At the highest level, it is a backbone network currently comprising 16 nodes connected to a 45Mb/s facility which 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.
Negative Acknowledgment (NAK): Response to receipt of a corrupted packet of information. See also:
netiquette: A pun on "etiquette" referring to proper behavior on a network.
Netnews: See: Usenet
network: A computer network is a data communications system which interconnects computer systems at various different sites. A network may be composed of any combination of LANs, MANs or WANs. See also: Local Area Network , Metropolitan Area Network , Wide Area Network , internet
network address: The network portion of an IP address. For a class A network, the network address is the first byte of the IP address. For a class B network, the network address is the first two bytes of the IP address. For a class C network, the network address is the first three bytes of the IP address. In each case, the remainder is the host address. In the Internet, assigned network addresses are globally unique. See also: Internet , IP address , subnet address , host address , Internet Registry
Network File System (NFS): A protocol developed by Sun Microsystems, and defined in RFC 1094, which allows a computer system to access files over a network as if they were on its local disks. This protocol has been incorporated in products by more than two hundred companies, and is now a de facto Internet standard. [Source: NNSC]
Network Information Center (NIC): A NIC provides information, assistance and services to network users. See also: Network Operations Center
Network Information Services (NIS): A set of services, generally provided by a NIC, to assist users in using the network. See also: Network Information Center
Network News Transfer Protocol (NNTP): A protocol, defined in RFC 977, for the distribution, inquiry, retrieval, and posting of news articles. See also: Usenet