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Dual-Band Wireless A/G Broadband Router
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DSSS. OFDM is a scheme in which numerous signals of different frequencies
are combined to form a single signal for transmission on the medium.
OFDM works by breaking one high-speed data stream into a number of lower-
speed data streams, which are then transmitted in parallel. Each lower speed
stream is used to modulate a subcarrier. Essentially, this creates a multi-carrier
transmission by dividing a wide frequency band or channel into a number of
narrower frequency bands or sub-channels. OFDM is also used for other appli-
cations, including powerline networking.
Packet
- A unit of data routed between an origin and a destination in a network.
Packet Filtering
- Discarding unwanted network traffic based on its originat-
ing address or range of addresses or its type (e-mail, file transfer, etc.).
Partitioning
- To divide a resource or application into smaller pieces.
Passphrase
- Used much like a password, a passphrase simplifies the WEP
encryption process by automatically generating the WEP encryption keys for
Linksys products.
PC Card
- A credit-card sized removable module that contains memory, I/O,
or a hard disk.
PCI
(
P
eripheral
C
omponent
I
nterconnect) - A peripheral bus commonly used
in PCs, Macintoshes and workstations. It was designed primarily by Intel and
first appeared on PCs in late 1993. PCI provides a high-speed data path
between the CPU and peripheral devices (video, disk, network, etc.). There are
typically three or four PCI slots on the motherboard. In a Pentium PC, there is
generally a mix of PCI and ISA slots or PCI and EISA slots. Early on, the PCI
bus was known as a “local bus.”
PCI provides “plug-and-play” capability, automatically configuring the PCI
cards at startup. When PCI is used with the ISA bus, the only thing that is gen-
erally required is to indicate in the CMOS memory which IRQs are already in
use by ISA cards. PCI takes care of the rest.
PCI allows IRQs to be shared, which helps to solve the problem of limited IRQs
available on a PC. For example, if there were only one IRQ left over after ISA
devices were given their required IRQs, all PCI devices could share it. In a PCI-
only machine, there cannot be insufficient IRQs, as all can be shared.
NetBIOS
- The native networking protocol in DOS and Windows networks.
Although originally combined with its transport layer protocol (NetBEUI),
NetBIOS today provides a programming interface for applications at the ses-
sion layer (layer 5). NetBIOS can ride over NetBEUI, its native transport,
which is not routable, or over TCP/IP and IPX/SPX, which are routable proto-
cols.
NetBIOS computers are identified by a unique 15-character name, and
Windows machines (NetBIOS machines) periodically broadcast their names
over the network so that Network Neighborhood can catalog them. For TCP/IP
networks, NetBIOS names are turned into IP addresses via manual configura-
tion in an LMHOSTS file or a WINS server.
There are two NetBIOS modes. The Datagram mode is the fastest mode, but
does not guarantee delivery. It uses a self-contained packet with send and
receive name, usually limited to 512 bytes. If the recipient device is not listen-
ing for messages, the datagram is lost. The Session mode establishes a connec-
tion until broken. It guarantees delivery of messages up to 64KB long.
Network
- A system that transmits any combination of voice, video, and/or
data between users.
Network Mask
- Also known as the “Subnet Mask.”
NIC
(
N
etwork
I
nterface
C
ard) - A board installed in a computer system, usu-
ally a PC, to provide network communication capabilities to and from that
computer system. Also called an adapter.
Node
- A network junction or connection point, typically a computer or work
station.
Notebook (PC)
- A notebook computer is a battery-powered personal comput-
er generally smaller than a briefcase that can easily be transported and conve-
niently used in temporary spaces such as on airplanes, in libraries, at temporary
offices, and at meetings. A notebook computer, sometimes called a laptop com-
puter, typically weighs less than five pounds and is three inches or less in thick-
ness.
OFDM
- Developed for wireless applications, Orthogonal Frequency Division
Multiplexing (OFDM) technology offers superior performance-increased data
rates and more reliable transmissions-than previous technologies, such as