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An understanding of the following key
points should have been achieved:
- All matter is composed of atoms, and
the three main parts of an atom are: protons, neutrons, and
electrons. The protons and neutrons are located in the center part
of the atom (nucleus)
- Electrostatic discharge (ESD) can
create serious problems for sensitive electronic equipment
- Attenuation refers to the resistance
to the flow of electrons and why a signal becomes degraded as it
travels
- Currents flow in closed loops called
circuits, which must be composed of conducting materials and must
have sources of voltage
- A multimeter is used to measure
voltage, current, resistance, and other electrical quantities
expressed in numeric form
- Three types of copper cables used in
networking are: straight-through, crossover, and rollover
- Coaxial cable consists of a hollow
outer cylindrical conductor that surrounds a single inner wire
conductor
- UTP cable is a four-pair wire medium
used in a variety of networks
- STP cable combines the techniques of
shielding, cancellation, and twisting of wires
- Optical fiber is a very good
transmission medium when it is properly installed, tested, and
maintained
- Light energy, a type of
electromagnetic energy wave, is used to transmit large amounts of
data securely over relatively long distances
- The light signal carried by a fiber
is produced by a transmitter that converts an electrical signal into
a light signal
- The light that arrives at the far
end of the cable is converted back to the original electrical signal
by the receiver
- Fibers are used in pairs to provide
full duplex communications
- Light rays obey the laws of
reflection and refraction as they travel through a glass fiber,
which allows fibers with the property of total internal reflection
to be manufactured
- Total internal reflection makes
light signals stay inside the fiber, even if the fiber is not
straight
- Attenuation of a light signal
becomes a problem over long cables especially if sections of cable
are connected at patch panels or spliced
- Cable and connectors must be
properly installed and thoroughly tested with high quality optical
test equipment before their use
- Cable links must be tested
periodically with high quality optical test instruments to check
whether the link has deteriorated in any way
- Care must always be taken to protect
eyes when intense light sources like lasers are used
- Understanding the regulations and
standards that apply to wireless technology will ensure that
deployed networks will be interoperable and in compliance
- Compatibility problems with NICs are
solved by installing an access point (AP) to act as a central hub
for the WLAN
- Three types of frames are used in
wireless communication: control, management, and data
- WLANs use Carrier Sense Multiple
Access/Collision Avoidance (CSMA/CA)
- WLAN authentication is a process
that authenticates the device, not the user
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