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Glossary

LSA acknowledgement

A Link State Advertisement acknowledgement is

sent from a router back to an originating router to acknowledge receipt of an
LSA from an OSPF router.

LSA flooding

OSPF floods the network with Link State Advertisements if

a change in the network occurs, permitting rapid convergence.

LUNI

LAN Emulation User-to-Network Interface: Defining the interface

between the LAN Emulation Client (LEC) and the LAN Emulation Server
(LES), LUNI is the ATM Forum's standard for LAN Emulation on ATM net-
works. See also: LES and LECS.

LZW algorithm

A data-compression process named for its inventors,

Lempel, Ziv, and Welch. The algorithm works by finding longer and longer
strings of data to compress with shorter representations.

MAC

Media Access Control: The lower sublayer in the Data Link layer, it

is responsible for hardware addressing, media access, and error detection of
frames. See also: Data Link layer and LLC.

MAC address

A Data Link layer hardware address that every port or

device needs in order to connect to a LAN segment. These addresses are used
by various devices in the network for accurate location of logical addresses.
MAC addresses are defined by the IEEE standard and their length is six char-
acters, typically using the burned-in address (BIA) of the local LAN inter-
face. Variously called "hardware address," "physical address," "burned-in
address," or "MAC layer address."

MacIP

In AppleTalk, the Network layer protocol encapsulating IP packets

in Datagram Delivery Protocol (DDP) packets. MacIP also supplies substi-
tute ARP services.

MAN

metropolitan area network: Any network that encompasses a met-

ropolitan area; that is, an area typically larger than a LAN but smaller than
a WAN. See also: LAN.

Manchester encoding

A method for digital coding in which a mid-bit

time transition is employed for clocking, and a 1 (one) is denoted by a high
voltage level during the first half of the bit time. This scheme is used by
Ethernet and IEEE 802.3.

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