Network Everywhere NWP11B User Manual page 19

and at meetings. A notebook computer, sometimes called a laptop computer,
typically weighs less than five pounds and is three inches or less in thickness.
Packet - A unit of data routed between an origin and a destination in a network.
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 (Peripheral Component Interconnect) - 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.
PCMCIA (Personal Computer Memory Card International Association) - An
industry group organized in 1989 to promote standards for a credit card-size
memory or I/O device that would fit into a personal computer, usually a note-
book or laptop computer.
Roaming - In an infrastructure mode wireless network, this refers to the abili-
ty to move out of one access point's range and into another and transparently
reassociate and reauthenticate to the new access point. This reassociation and
reauthentication should occur without user intervention and ideally without
interruption to network connectivity. A typical scenario would be a location
with multiple access points, where users can physically relocate from one area
to another and easily maintain connectivity.
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Network Everywhere Series
™
Wireless Notebook Adapter
Router - Protocol-dependent device that connects subnetworks together.
Routers are useful in breaking down a very large network into smaller subnet-
works; they introduce longer delays and typically have much lower throughput
rates than bridges.
RTS (Request To Send) - An RS-232 signal sent from the transmitting station
to the receiving station requesting permission to transmit.
Server - Any computer whose function in a network is to provide user access
to files, printing, communications, and other services.
Software - Instructions for the computer. A series of instructions that performs
a particular task is called a "program." The two major categories of software are
"system software" and "application software." System software is made up of
control programs such as the operating system and database management sys-
tem (DBMS). Application software is any program that processes data for the
user.
A common misconception is that software is data. It is not. Software tells the
hardware how to process the data.
SOHO (Small Office/Home Office) - Market segment of professionals who
work at home or in small offices.
Spread Spectrum - Spread Spectrum technology is a wideband radio frequen-
cy technique developed by the military for use in reliable, secure, mission-crit-
ical communications systems. It is designed to trade off bandwidth efficiency
for reliability, integrity, and security. In other words, more bandwidth is con-
sumed than in the case of narrowband transmission, but the trade off produces
a signal that is, in effect, louder and thus easier to detect, provided that the
receiver knows the parameters of the spread-spectrum signal being broadcast.
If a receiver is not tuned to the right frequency, a spread-spectrum signal looks
like background noise. There are two main alternatives, Direct Sequence
Spread Spectrum (DSSS) and Frequency Hopping Spread Spectrum (FHSS).
SSID (Service Set IDentifier) - A unique name shared among all points in a
wireless network. The SSID must be identical for each point in the wireless net-
work and is case-sensitive.
Storage - The semi-permanent or permanent holding place for digital data.
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