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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