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LED (Light Emitting Diode): The lights on a
hardware device representing the activity
through the ports.
MAC (Medium Access Control) Address: A
unique number that distinguishes network
cards.
Mbps (Mega Bits Per Second): A
measurement of millions of bits per
second.
MDI/X (Media Dependent Interface/Cross-
over): Port on a network hub or switch
that crosses the incoming transmit lines
with the outgoing receive lines.
MHz (MegaHertz): One million cycles per
second.
MIB II: A database containing performance
information and statistics on each device in
a network.
MIPS (Million Instructions Per Second): A
measurement of processing speed.
NAT (Network Address Translation): An
internet standard that enables a LAN to
use one set of IP addresses for internal
trafc and a second set for external trafc.
NIC (Network Interface Card): An
expansion card connected to a computer
so the computer can be connected to a
network.
Packet: A block of data that is transferred
as a single unit, also called a frame or a
block.
Packet Filtering: Discarding unwanted
network trafc based on its originating
address or its type.
PCI (Peripheral Component Interconnect):
A bus that is connected directly to the
CPU.
PCMCIA (Personal Computer Memory Card
International Association) Card: Removable
module that adds features to a portable
computer.
Glossary