Network+ 2005 Acronyms & Abbreviations (Part I)

Front 1

PDU

Back 1

Protocol Data Unit

Front 2

WLL

Back 2

Wireless Local Loop

Front 3

LAN

Back 3

Local Area Network

Front 4

MAN

Back 4

Metropolitan Area Network

Front 5

WAN

Back 5

Wide Area Network

Front 6

NOS

Back 6

Network Operating System

Front 7

ANSI

Back 7

American National Standards Institute

Front 8

EIA

Back 8

Electronic Industries Alliance

Front 9

TIA

Back 9

Telecommunications Industry Association

Front 10

IEEE

Back 10

Institute of Electrical and Electronics Engineers

Front 11

ISO

Back 11

International Organization for Standardization

Front 12

ITU

Back 12

International Telecommunications Union

Front 13

ISOC

Back 13

Internet Society

Front 14

IAB

Back 14

Internet Architecture Board

Front 15

IETR

Back 15

Internet Engineering Task Force

Front 16

IANA

Back 16

Internet Assigned Numbers Authority

Front 17

ICANN

Back 17

Internet Corporation for Assigned Names and Numbers

Front 18

OSI Model

Back 18

Open Systems Interconnect Model

Front 19

SYN

Back 19

Synchronization - a client's TCP protocol first sends a SYN packet request to a web server.

Front 20

SYN-ACK

Back 20

Synchronization-Acknowledgement - web server responds to the client's SYN packet request.

Front 21

MTU

Back 21

Maximum Transmission Unit

Front 22

CRC

Back 22

Cyclic Redundancy Check

Front 23

FCS

Back 23

Frame Check Sequence - used in error checking

Front 24

LLC

Back 24

Logical Link Control

Front 25

MAC

Back 25

Media Access Control

Front 26

FM

Back 26

Frequency Modulation - data is modified to follow a particular path.

Front 27

AM

Back 27

Amplitude Modulation - the amplitude is modified.

Front 28

TDM

Back 28

Time Division Multiplexing - divides a channel into multiple intervals of time.

Front 29

WDM

Back 29

Wavelength Division Multiplexing - one fiber-optic connection can carry multiple light signals simultaneously, and channels are designated by different colors of light.

Front 30

DWDM

Back 30

Dense Wave Division Multiplexing - A single fiber in a fiber-optic cable can carry between 80-160 channels.

Front 31

EMI

Back 31

Electromagnetic Interference - noise cause by waves emanating from electrical devices/cables. (Example: power lines, TVs, copiers, flourescent lights)

Front 32

RFI

Back 32

Radiofrequency Interference - one type of EMI cause by radio waves.

Front 33

RTT

Back 33

Round-Trip Time - length of time it takes a packet to go from sender to receiver and back (measured in milliseconds).

Front 34

RG (Coaxial Cables)

Back 34

Radio Grade - Rating of different types of Coaxial cable.

Front 35

STP

Back 35

Shielded Twisted-Pair - more expensive, but more resistant to crosstalk.

Front 36

UTP

Back 36

Unshielded Twisted-Pair - less expensive, but less resistant to crosstalk.

Front 37

SMF

Back 37

Single-Mode Fiber - high bandwidth, long distances, expensive, single path of laser light (used to connect carriers/facilities)

Front 38

MMF

Back 38

Multi-Mode Fiber - larger core (diameter), so light travels at different angles (used to connect router to switch or server to backbone)

Front 39

CIDR

Back 39

Classless Inter-Domain Routing

Front 40

LOS

Back 40

Line-Of-Sight - Signal travels directly in a straight line from the transmitter to the intended receiver. This type of propagation uses the least amount of energy and results in the clearest possible signal.

Front 41

FHSS

Back 41

Frequency Hopping Spread Spectrum - Signals jump between several different frequencies within a band in a synchronization pattern.

Front 42

DSSS

Back 42

Direct Sequence Spread Spectrum - A signal's bits are distributed over an entire frequency band at once. The receiver can reassemble the original upon receipt.

Front 43

AP

Back 43

Access Point - device that accepts wireless signals from multiple nodes and retransmits them to the rest of the network.

Front 44

ICMP

Back 44

Internet Control Message Protocol - Network layer protocol that reports on the success or failure of data delivery; also it can indicate which networks are congested.

Front 45

IGMP

Back 45

Internet Group Management (Multicast) Protocol - Network layer protocol that mananges multicasting, which is the transmission menthod that allows one node to send data to a defined group of nodes (point-to-multipoint method).

Front 46

ARP

Back 46

Address Resolution Protocol - Network layer protocol that obtains the MAC address of a host (node), then creates a database that maps the MAC address to the host's IP address.

Front 47

ARP Table

Back 47

Database of recognized MAP-to-IP addresses on a hard disk.

Front 48

Dynamic ARP Table vs. Static ARP Table

Back 48

Dynamic: entries are created when a client makes an ARP request that cannot be satisfied by data already in the ARP table. Static: entries that are manually entered into the ARP table using the ARP utility.

Front 49

RARP

Back 49

Reverse Address Resolution Protocol - allows a client to send a broadcast message with its MAC address and receive an IP address in reply (the opposite fuction of ARP).

Front 50

BOOTP

Back 50

Bootstrap Protocol - Application layer protocol that uses a central list of IP addresses and their associated devices' MAC addresses to assign IP addresses to clients dynamically.

Front 51

DHCP

Back 51

Dynamic Host Configuration Protocol - Automated means of assigning a unique IP address to every device on the network; Application layer of OSI; replacement for BOOTP; operates in a similar manner to BOOTP; does not require the network administrator to maintain a table of IP and MAC addresses on the server.

Front 52

TLD

Back 52

Top-Level Domain (Example: www.novell.com - .com is the top-level, novell is 2nd, and www is 3rd.

Front 53

DNS

Back 53

Domain Name System - associates names with IP addresses; Application layer of OSI; computers are related in a hierarchical manner, with 13 computer (root servers), acting as the ultimate authorities.

Front 54

DDNS

Back 54

Dynamic DNS - Service provider runs a program on the user's computer that notifies the service provider when the user's IP address changes; DDNS doesn't take the place of DNS, but is an additional service available for a small fee; good option for home or small office users.

Front 55

FTP

Back 55

File Transfer Protocol - Application layer protocol used to send and receive files via TCP/IP. Start FTP utility by typing FTP from command prompt. Many FTP hosts accept anonymous logins - user name anonymous and email address for password. To learn more about FTP commands, type help at FTP command prompt.

Front 56

TFTP

Back 56

Trivial File Transfer Protocol - Application layer protocol that enables file transfers between computers, but it's simpler than FTP. TFTP relies on UDP at the Transport layer, it's connectionless, and doesn't requite logon. TFTP doesn't allow directory browsing like FTP.

Front 57

NTP

Back 57

Network Time Protocol - Application layer protocol used to synchronize the clocks of computers on a network. NTP depends on UDP for Transport layer services.

Front 58

NNTP

Back 58

Network News Transport Protocol - Facilitates the exchange of newgroup messages between multiple servers and users. Newsgroups distribute messages to a wide group of users at once rather than one user to another like email.

Front 59

PING

Back 59

Packet Internet Groper - utility that can verify that TCP/IP is installed, bound to NIC, configured correctly and communicating with the network. First, a signal (echo) is sent to another computer - the other computer rebroadcasts the signal (echo reply).

Front 60

IPX/SPX

Back 60

Internetwork Packet Exchange/Sequenced Packet Exchange - developed by Xerox, then modified by Novell in the 80s for NetWare. Microsoft's implemenatation of IPX/SPX is call NWLink.

Front 61

IPX

Back 61

Internetwork Packet Exchange - operates at Network layer of OSI and provides logical addressing and internetworking services similar to IP in TCP/IP; connectionless; doesn't guarantee data will be delivered in sequence or without errors.

Front 62

SPX

Back 62

Sequenced Packet Exchange - Transport layer of OSI; ensures that data are received whole, in sequence and error free. SPX is like TCP in TCP/IP; connection-oriented; must verify that a session has been established before transmission of data.

Front 63

NetBIOS

Back 63

Network Basic Input Output System - protocol originally designed by IBM to provide Transport and Session Layer services for applications running on small, homogenous networks.

Front 64

NetBEUI

Back 64

NetBIOS Enhanced User Interface - Microsoft's adaption of NetBIOS. NetBEUI is efficient protocol that uses few resources, provides error correction, and requires little configuration. Allows only 254 connections, not good security and not routable.

Front 65

WINS

Back 65

Windows Internet Naming Services - Provides a means of resolving NetBIOS names to IP addresses.

Front 66

VLAN

Back 66

Virtual Local Area Network - created by switches, VLANs logically separate networks within networks by grouping a number of ports into a broadcast domain.

Front 67

RIP

Back 67

Routing Information Protocol (IP and IPX) - oldest protocol, factors in only the number of hops between nodes when determining best path, but doesn't consider congestion or link speed. Interior routing protocol, so doesn't work well in a very large network environment.

Front 68

OSPF

Back 68

Open Shortest Path First - interior and border routers, can coexist with RIP. No hop limits, more complex algorithm for determining best path, fast convergence time, commonly used on LANs with mixed router manufacturers.

Front 69

EIGRP

Back 69

Enhanced Interior Gateway Routing Protocol (IP, IPX and AppleTalk) - Interior and border routers, fast convergence time, low network overhead, supports multiple protocols and accomodates very large heterogeneous networks (Cisco Routers only).

Front 70

BGP

Back 70

Border Gateway Protocol (IP) - Routing protocol of Internet backbones, so not used between nodes on a LAN. Most complex protocol.