Networking Terms

TIA

Telecommunications Industries Association .

FDDI

Fiber Distributed Data Interface is a network architecture normally used to send longer distances. Topology is ring with two counter rotating rings for reliability with no hubs. Cable type is fiber-optic.

FTP

File Transfer Protocol.

FTP

File Transport Protocol is a TCP/IP protocol running at the application layer.

Server

For the most part it provides resources on the network for other computers to use.

FDMA

Frequency Division Multiple Access divides the cellular network into 30Khz channels.

DECnet

From Digital Equipment Corporation is a suite of protocols which may be used on large networks that integrate mainframe and minicomputer systems

GSM

Global System for Mobile Communications.

IPIP tunneling

Tunneling IP packets in IP packets. Used for VPN tunneling.

ISDN

Integrated Services Digital Network is a method of sending voice and data information on a digital phone line. Two 64Kbps B-channels with one 16Kbps D channel is provided with basic ISDN service

X.400

International Telecommunication Union standard defines transfer protocols for sending mail between mail servers.

ITU

International Telecommunication Union.

CCITT

International Telegraph and Telephone Consultative Committee.

IAB

Internet Architecture Board

IANA

Internet Assigned Numbers Authority.

ICMP

Internet Control Message Protocol is used to perform network error reporting and status. It works at the transport layer. RFC 792.

IDC

Internet Database collector.

IETF

Internet Engineering Task Force. Sets Internet technical standards.

IGMP

Internet Group Management Protocol, used for managing multicast groups. RFC 1112.

IMAP4

Internet Mail Access Protocol version 4 is the replacement for POP3

InterNIC

Internet Network Information Center, the authority for allocating internet addresses.

IP

Internet Protocol os used for software addressing of computers and works at the data link layer. RFC 791.

IRTF

Internet Research Task force.

ISAKMP/Oakley

Internet Security Association and Key Management Protocol Authentication.

ISAPI

Internet Server Application Programming Interface

ISP

Internet Service Provider

ISOC

Internet Society, promotes internet policies.

IPSec

Internet protocol security, developed by IETF, implemented at layer 3. it is a collection of security measures that address data privacy, integrity, authentication, and key management, in addition to tunneling. Used for VPN.

IPX

Internetwork Packet Exchange supports the transport and network layers of the OSI network model. Provides for network addressing and routing. It provides fast, unreliable, communication with network nodes using a connection less datagram service.

IRQ

Interrupt Request

Spread spectrum

It uses several frequencies at the same time.

MTA

Message transfer agent is used to pass mail from the sending machine to the receiving machine. There is a MTA program running on both the sending and receiving machine. Sendmail is a MTA.

MOTIS

Message-oriented text interchange system.

NNTP

Network News Transport Protocol is used to link newsgroups for discussions on the web

NetDDE

Network dynamic data exchange.

NIC

Network interface card. Also called LAN adapters.

Router

Routes data packets between two networks. It reads the information in each packet to tell where it is going.

RIP

Routing Information Protocol, a dynamic routing protocol. A distance-vector algorithm is used to calculate the best route for a packet. RFC 1058, 1388 (RIP2).

RTMP

Routing table maintenance protocol is used to update routers with information about network status and address tables. The whole address table is sent across the network.

SMS

SMS - Systems Management Server from Microsoft can collect information of software on each computer and can install and configure new software on the client computers. It will also monitor network traffic.

RADIUS

Remote Authentication Dial-In User Service is used for dial in clients to connect to other computers or a network. It provides authentication and accounting when using PPTP or L2TP tunneling.

RPC

Remote Procedure Call. A protocol invented by Sun Microsystem to allow remote computers to invoke functions on other hosts. RFC 1057.

Rlogin

Remote login between UNIX hosts. This is outdated and is replaced by Telnet.

Telnet

Remote session at the application layer. RFC 854.

RR

Resource Records are a part of the DNS database.

RARP

Reverse Address Resolution Protocol used for diskless computers to determine their IP address using the network. It works at the data link layer. RFC 903

VPN

Virtual Private Networking. The function of VPN is to allow two computers or networks to talk to each other over a transport media that is not secure, but the network is made secure by VPN security protocols.

WAN

Wide Area Network is larger than a MAN and may be an enterprise network or a global network.

Brouter

Will function similar to a bridge for network transport protocols that are not routable, and will function as a router for routable protocols.

WINS

Windows Internet Name Service is the Microsoft implementation of NetBIOS name service.

WML

Wireless markup language is another name for HDML.

W3C

World Wide Web Consortium, sets standards for the web working with the IETF.

ZIP

Zone information protocol used with RTMP to map zones. Routers use zone information tables (ZITs) to define network addresses and zone names.

Redirector

it runs on a windows operating system and directs requests for network resources to the appropriate server and makes network resources seem to be local resources.

attenuation

signal loss due to impedance.

5 4 3 rule

there can be 5 network segments with 4 repeaters, and 3 of the segments can be connected to computers

CSMA/CD

Carrier-sense multiple-access with collision detection for controlling access to the network media.

Peer

A computer that can act as both a client and a server.

Gateway

A gateway can translate information between different network data formats or network architectures. It can translate TCP/IP to AppleTalk so computers supporting TCP/IP can communicate with Apple brand computers. Not the same as a default gateway used by a client to send packets to.

Multihomed

A host with multiple IP addresses.

Sector Sparing

A method of fault tolerance that automatically identifies and marks bad sectors as not available. It is also called hot-fixing.

Token Ring

A network architecture developed by IBM which sends tokens around a ring of computers to allow media access. Standardized to IEEE 802.5

Ethernet

A network architecture that uses carrier-sense multiple-access with collision detection (CSMA/CD) for controlling access to the network media and baseband broadcasts. It uses star topology.

S/Key

A one time password system, secure against replays. RFC 2289.

Subnet

A part of a network. A class B network may have several class C subnets. Usually routers are used to connect subnets.

Protocol

A set of standards sets of standards that define all operations within a network. There are various protocols that operate at various levels of the OSI network model such as transport protocols include TCP, SPX.

Unicast

A transmission to a single interface card.

Broadcast

A transmission to all interface cards on the network.

Hub

A type of repeater used on several network architectures which usually connects several stations.

CDPD

Cellular Digital Packet Data will allow network connections for mobile users using satellites.

AGP

Accelerated Graphics Port. This bus is developed for fast video cards. It is currently up to 4X mode speed.

AU

Access Unit provides access to resources like fax, telex, and teletex.

ASP

Active Server Pages is Microsoft's web server technology which can run Visual Basic or JAVA script.

ARP

Address resolution Protocol is used to resolve the hardware address of a card to package the ethernet data. It works at the data link layer. RFC 826.

AMPS

Advanced Mobile Phone Service is analog cellular phone service.

APPC

Advanced Peer-to-Peer Communications provides peer to peer services at the transport and session layer.

APPN

Advanced Peer-to-Peer Networking supports the computer connections at the network and transport layers.

cellular

An 800 Mhz band for mobile phone service.

XML

Extensible Markup Language is a subset of SGML and is used widely on the web.

EGP

Exterior Gateway Protocol. Used between routers of different systems.

AFP

AppleTalk Filing protocol - Makes network files appear local by managing file sharing at the presentation layer.

ATP

AppleTalk Transaction Protocol provides a Transport Layer connection between computers.

ADSP

AppleTalk data stream protocol manages the flow of data between two established socket connections.

AEP

AppleTalk echo protocol uses echoes to tell if a computer, or node, is available.

ASP

AppleTalk session protocol controls the starting and ending of sessions between computers called nodes. It works at the session level.

ARUP

AppleTalk update routing is a newer version of RTMP.

API

Application Programming Interface.

ATM

Asynchronous Transfer Mode may be used over a variety of media with both baseband and broadband systems. It uses fixed length data packets of 53 bytes called cell switching.

ARCnet

Attached Resource Computer Network is an architecture using star and bus topology.

BDC

Backup Domain Controller is a backup for a PDC

MBONE

Being on the MBONE means you are on a network that supports multicasting.

BSC

Binary Synchronous Communication sends bits in frames which are timed sequences of data. A possible SNA communications architecture,

BOOTP

Boot Protocol. RFC 951, 1542.

BGP

Border Gateway Protocol, a dynamic routing protocol. RFC 1267.

BNC

British Naval Connector.

CHAP

Challenge Handshake Authentication Protocol is a three way handshake protocol which is considered more secure than PAP.

CSU

Channel service unit used to connect to digital leased lines on the line side.

CIDR

Classless Inter Domain Routing.

CDMA

Code division multiple access allows transmission of voice and data over a shared part of radio frequencies. This is also called spread spectrum.

Link

Connects two network devices. Implemented by the data link layer.

CRC

Cyclic Redundancy check is a set of trailing data bytes in a message used to determine if an error occurred in a message.

DLC

Data Link Control operates at the data link layer and is designed for communications between Hewlett-Packard network printers and IBM mainframe computers on a DECnet network.

Baseband

Data bits are defined by discrete signal changes.

DBMS

Database Management Systems are used to share data on a network.

DDP

Datagram Delivery Protocol is a routable protocol that provides for data packet transportation. It operates at the network layer at the same level of the IP protocol.

DUN

Dial up networking.

D-AMPS

Digital AMPS using TDMA to divide the channels into three channels.

DAT

Digital Audio Tape

DNA

Digital Network Architecture is a term from DECNet

DDS

Digital data service is a leased dedicated digital line.

DSU

Digital service unit used to connect to digital leased lines on the LAN side.

DVM

Digital volt meter.

DRDA

Distributed Relational Database Architecture is from IBM.

DTD

Document Type Definition.

DNS

Domain Name System is used on the internet to correlate between IP address and readable names. RFC 1034, 1035, 1535-1537, 1591.

DAS

Dual attachment stations are used by FDDI networks for servers and concentrators are attached to both rings.

DHCP

Dynamic Host Configuration Protocol is used to assign IP addresses dynamically to network cards works at the application layer. RFC 1541.

DDE

Dynamic data exchange.

Interference

Electromagnetic Interference (EMI). Crosstalk - When wires pick up electromagnetic signals from nearby wires also carrying signals.

EMI

Electromagnetic Interference.

EIA

Electronic Industries Association .

EIGRP

Enhanced Interior Gateway Routing Protocol integrates the bese capabilities of link-state protocols with distance vector protocols capabilities.

Frame Relay

Error checking is handled by devices at both sides of the connection. Frame relay uses frames of varying length and it operates at the data link layer of the OSI model. A permanent virtual circuit (PVC) is established between two points on the network. Frame relay speed is between 56Kbps and 1.544Mbps.

EISA

Extended ISA used when the 80286 through 80486 series microprocessors were being produced. It is backward compatible with ISA.

Thicknet

Half inch rigid cable. Maximum cable length is 500 meters. Transmission speed is 10Mbps. Expensive and is not commonly used. (RG-11 or RG-8).

HDML

Handheld Device Markup Language is a version of HTML only allowing text to be displayed.

HTML

Hypertext Markup Language is the format many files for web viewing are in. It is a language with "mark-up" text included for formatting.

HTTP

Hypertext Transfer Protocol is the protocol used to communicate between web servers and web browser software clients.

Datagram

IP header and what is called a message or segment. The message or segment is a transport header (TCP or UDP) and application data. The term datagram is used to describe the information before IP fragmentation or after reassembly.

Packet

Includes an IP header and data. It may be a complete IP datagram or a fragment of an IP datagram.

MS

Message Store is a storage area for messages that can't be delivered immediately when the recipient is off-line.

Bandwidth

Indicates the amount of data that can be sent in a time period. Measured in Mbps which is one million bits per second.

ISA

Industry Standard Architecture internal computer bus. Used when the original 8088 8bit microprocessor based personal computers were produced. (16 bit).

Infared

Infared is just below the visible range of light between 100Ghz and 1000Thz.

L2TP

Layer 2 tunneling protocol (RFC 2661). Used for VPN tunneling.

L2F

Layer2 Forwarding, works at the link layer of the OSI model. It has no encryption. Being replaced by L2TP. It is used for VPN.

LCP

Link Control Protocol

LLC

Loc\gical link control is the interface between the lower and upper layer networking protocols.

LAN

Local Area Network

LDA

Local delivery agent on the receiving machine receives the mail from its MTA. This program is usually procmail.

LU

Logical Units are ports that users use to access network resources is an SNA term.

MUA

Mail users agent. This is the program a user will use to type e-mail. It usually incorporates an editor for support. The user types the mail and it is passed to the sending MTA. This may also be called the user agent (UA).

Backbone

Main cable used to connect computers on a network.

MIB

Management Information BASE specifies variables the network elements maintain. Works with the TCP/IP protocol SNMP.

MTU

Maximum Transmission Unit is the maximum size of each data packet for the ethernet protocol.

MAC

Media Access Control address. Basically a network card unique hardware address.

MHS

Message Handling Service by Novell is used for mail on Netware networks.

MAN

Metropolitan area network refers to a network which connects several LANS over various media that is large enough to cover an area the size of a city.

MCI

Microchannel architecture by IBM and used mainly on IBM brand computers for the internal bus. Established in 1988. (16 or 32 bits).

MAPI

Microsoft's Messaging API which is incorporated throughout Microsoft's office products supports mail at the application level.

wireless bridge

Microwave or infared is used between two line of site points where it is difficult to run wire.

MDBS

Mobile Data Base Station reviews all cellular channels at cellular sites.

MTP

Multicast Transport Protocol is a new transport layer protocol designed for reliable multicast network message transport.

T Carrier

Multiplexors are used to allow several channels on one line. The T1 line is basic T Carrier service.

MIME

Multipurpose Internet Mail Extension is the protocol that defines the way files are attached to SMTP messages.

MAU

Multistation access unit used by Token Ring Networks.

NBP

Name-binding protocol of the AppleTalk suite of protocols translates addresses into names.

NADN

Nearest Active Downstream Neighbor is a Token ring Architecture term.

NAUN

Nearest Active Upstream Neighbor is a Token ring Architecture term.

NetBEUI

NetBIOS Extended User Interface works at the transport layer and provides data transportation. It is not a routable transport protocol which is why NBT exists on large networks to use routable TCP protocol on large networks.

NBF

NetBIOS Frame Protocol.

NBNS

NetBIOS Name Server. A server that maps NetBIOS names to IP addresses. This service is provided by the nmbd daemon on Linux.

NBT

NetBIOS over TCP/IP defined by RFC 1002.

NCP

NetWare Core Protocol provides for client/server interactions such as file and print sharing. It works at the application, presentation, and session levels.

NAT

Network Address Translation.

NAU

Network Addressable Units is an SNA term.

NetBIOS

Network Basic Input Output System by Microsoft.

NCP

Network Control Program performs routing, session management tasks. It runs in the communications controller. It is an SNA networking term.

NDIS

Network Driver Interface Specification from Microsoft, is used on Microsoft networks. It allows multiple protocols to be used on a network card and supports the data link layer of the network model.

NFS

Network File System. A protocol that allows UNIX and Linux systems remotely mount each other's file systems. RFC 1094

TACACS

Offers authentication, accounting, and authorization.

ODI

Open Data-link Interface operates at the data link layer allowing IPX to work with any network interface card.

ODBC

Open Database Connectivity (ODBC) from Microsoft lets application developers integrate database connections in applications. It is an application programming interface (API). ODBC drivers convert an application's query int SQL and send it to the database engine program.

OSPF

Open Shortest Path First, a dynamic routing protocol. RFC 1247.

OSI

Open Systems Interconnect is a suite of protocols developed by the International Standards Organization (ISO) which corresponds with the layers of the OSI model.

OC

Optical Carrier level, see SONET.

PAP

Password Authentification Protocol is a two way handshake protocol designed for use with PPP.

PCI

Peripheral Component Interconnect internal computer bus. The popular expansion bus of choice. It is significantly faster than EISA. This is a 32bit bus with plug and play capability from Intel.

PCS

Personal communications Service is a 1.9 Ghz band for mobile phones.

PU

Physical Units are a network device used to communicate with hosts. It is an SNA term.

RAS

Remote Access Service (RAS) with Windows NT allows users connecting to the network using a modem to use network resources. The NT RAS server can handle 256 connections.

POP

Point of presence is each point at the end of the transport media (internet) when talking about VPN.

PPP

Point to Point Protocol, used for serial connections to a network ot the internet. (RFC 1332, 1548)

PPTP

Point to point tunneling protocol (RFC 2637) Used for VPN tunneling.

POP3

Post Office Protocol version 3 is used by clients to access an internet mail server to get mail. It is not a transport layer protocol.

PDC

Primary Domain Controller is an NT server providing central control of user access permissions and accounts on a network.

PAP

Printer access protocol of the AppleTalk suite of protocols manages information between workstations and printers.

Bridge

Read the outermost section of data on the data packet, to tell where the message is going. It reduces the traffic on other network segments, since it does not send all packets but only sends packets intended for that segment they are attached to.

RAID

Redundant Array of Inexpensive disks is a fault tolerant method of storing data, meaning that a failure can occur and the system will still function.

Intranet

Refers to using internet technologies such as a web server on an internal network.

SPX

Sequenced Packet Exchange operates at the transport layer providing connection oriented communication on top of IPX.

SLIP

Serial Line interface Protocol used to connect serially to a network or internet. RFC 1055, 1144 (Compressed). Replaced by PPP.

SMB

Server Message Block protocol works at the presentation level to provide peer to peer communication.

SAP

Service Advertising Protocol packets are used by file and print servers to periodically advertise the address of the server and the services available. It works at the application, presentation, and session levels.

Internetwork

Several subnets connected together using routers.

STP

Shielded Twisted Pair cable. 100 meter maximum length. 16-155 Mbps speed. Lower electrical interference than UTP

SMTP

Simple Mail Transfer Protocol is a TCP protocol for mail transport running at the application layer. RFC 821, 822.

SNMP

Simple Network Management Protocol. RFC 1155, 1157, 1213, 1441.

SAS

Single Attachment stations attached to one ring and used by FDDI networks to attach workstations to concentrators.

SLED

Single Large Inexpensive disk - The concept that a large disk costs less per amount of storage than several smaller ones. Somehow this concept is used as a means of fault tolerance.

SMAU

Smart Multistation Access Unit.

Plenum

Space above a false ceiling in an office area where heat ducts and cables may be run. Plenum cabling is special fire resistant cabling required for use in these areas due to fire hazards.

SGML

Standardized General Markup Language is the base language for document publishing and is used to define XML, HTML and more.

SQL

Structured Query Language is a database access language. It is used by most client/server database applications.

SMDS

Switched Multi-megabit Data Service uses fixed length cell switching and runs at speeds of 1.533 to 45Mbps.

SDLS

Synchronous Data Link Control is a possible SNA communications architecture.

SDH

Synchronous Digital Hierarchy

SONET

Synchronous Optical Network is a physical layer standard that defines voice, data, and video delivery methods over fiber optic media. It defines data rates in terms of optical carrier (OC) levels.

SNA

System Network Architecture by IBM is a suite of protocols mainly used with IBM mainframe and AS/400 computers.

SSCP

Systems Services Control Point manages all resources in the host's domain. An SNA term.

Impedance

The amount of resistance to the transmission device.

Direct sequence modulation

The data is broken into parts and transmitted simultaneously on multiple frequencies.

Media

The hardware method used to connect computers over a network. The three main types are copper cable, fiber optic cable, and wireless.

Architecture

The method that is used to transmit packets on a network. Sometimes the term architecture includes topology. An example is ethernet.

Topology

The shape of the physical connection of a network with regard to repeaters and networked computers. The three main types are ring, bus, and star.

Frequency hopping

The transmitter and receiver change predetermined frequencies at the same time (in a synchronized manner).

Segment

The unit of end-to-end transmission in the TCP protocol which consists of a TCP header followed by application data.

Frame

The unit of transmission in a link layer protocol, consisting of a link-layer header (ethernet) followed by a packet (IP header and data). It may be a part of a fragmented datagram.

Message

The unit of transmission in a transport layer protocol. A TCP segment is a message which consists of a transport protocol header followed by application data.

Thinnet

Thinnet uses a British Naval Connector (BNC) on each end. Thinnet is part of the RG-58 family of cable*. Maximum cable length is 185 meters. Transmission speed is 10Mbps.

Client

This computer requests resources for its use from a computer that provides the resource (a server).

X.500

This is a recommendation outlining how an organization can share objects and names on a large network. It is hierarchical similar to DNS, defining domains consisting of organizations, divisions, departments, and workgroups.

X.25

This is a set of protocols developed by the CCITT/ITU which specifies how to connect computer devices over a internetwork.

Mail notifier

This program notifies the recipient that they have mail. Normally this requires two programs, biff and comsat. Biff allows the administrator or user to turn on comsat service.

TDMA

Time Division Multiple Access uses time division multiplexing to divide each cellular channel into three sub channels to service three users at a time.

TDR

Time-domain reflectometer sends a sonar like electrical pulse down a cable and can determine the location of a break in the cable.

TLD

Top Level domain

Multicasting

Transmitting to a group of interface cards on the network.

TCP

Transport Control protocol is a connection oriented reliable protocol working at the transport layer. RFC 793.

TDI

Transport Driver Interface is a standard for passing messages between the drivers at the data link layer and the protocols working at the network layer such as IP or NetBEUI. It was produced by Microsoft.

TFTP

Trivial File Transfer Protocol. RFC 1350.

Network Operating System

Typically used to run computers that act as servers, but may be used on various types of computers today.

UNC

Universal Naming Convention is used to allow the use of shared resources without mapping a drive to them.

URL

Universal Resource Relocator is a term used to describe the name of a web based resource such as a web page or location of a file for down loading.

UTP

Unshielded Twisted Pair cable. Normally UTP contains 8 wires or 4 pair. 100 meter maximum length. 4-100 Mbps speed.

Resolver

Used as part of DNS, it is the client side asking for DNS information.

Repeater

Used on a network to regenerate signals to be sent over long distances or tie computers together on a network.

Shielding

Used to minimize interference.

UDP

User Datagram Protocol is a connection less unreliable protocol working at the transport layer. RFC 768.

UA

Users agent. This is the program a user will use to type e-mail. It usually incorporates an editor for support. The user types the mail and it is passed to the sending MTA. This may also be called the mail user agent (MUA).

Broadband

Uses analog signals to divide the cable into several channels with each channel at its own frequency. Each channel can only transmit one direction.

VIM

Vendor-Independent Messaging protocol from Lotus supports mail at the application level and is supported by many vendors exclusive of Microsoft.