MIDTERM - NETWORK TECHNOLOGY 1

Open Circuit

An _______________ occurs if the wire does not attach properly at the connector.

Video Signals

These are signals found in intensity variations in an image.

Power sum equal-level far-end crosstalk / PSELFEXT

This is derived from an algebraic summation of the individual ELFEXT effects on each pair by the other three (3) pairs.

Serial Transmission

This type of communication is used over the phone system because it provides one wire for data in each direction.

ST Connector, SC Connector / Straight Tip Connector, Subscriber Connector

Connectors used with fiber-optic cable are ______________________ and ________________________.

Microwave

It refers to a wireless medium that is used for unicast communication such as Bluetooth, 2G/3G cellular networks, satellite networks and radar, and wireless LANs (Wi-Fi). It doesn't follow the curvature of the earth and requires line of sight in order to work properly.

Serial Cable

The most widely used standards for serial data communications is the which is intended to operate over distances of up to 50 feet and has a communication speed that is equal to or less than 20Kbps.

Far-End Crosstalk / FEXT

The signal is sent from the local end and crosstalk is measured at the far end. The noise still travels back to the source, but it is attenuated as it returns. Due to attenuation, it creates less noise on a cable than NEXT.

Single-mode fiber optic cable

This fiber optic cable type allows light waves to travel along single path or in only one mode. It is used commonly for high speed transmission over long distances.

Multimode fiber optic cable

This fiber optic cable type allows light waves to travel into numerous paths through the core of the fiber at various angles. It is often applied to local area networks which encompass a much smaller transmission range.

Return Loss

This is a measure in decibels of all reflections that are caused by the impedance mismatches at all locations along the link.

Propagation Delay / Delay

This is a measurement of how long it takes for a signal to travel along the cable being tested.

Near-End Crosstalk / NEXT

This occurs when two (2) wires are near each other and untwisted. The energy from one (1) wire can wind up in an adjacent wire and vice versa. This can cause noise at both ends of a terminated cable.

Attenuation

This refers to signal loss due to impedance.

Short Circuit

A _______________ occurs if two (2) wires are connected to each other.

Number of Receivers

Data rate and distance are limited by multiple attachments for each attachment introduces some attenuation and distortion on the line.

Interference

Emanations from nearby cables cause frequency bands to overlap and make signal compete. This in turn, distorts or wipes out the signal.

Bandwidth

Higher data rate is achieved by means of a greater signal ___________________.

Crosstalk

It causes an interference with the signals that may be present on the two (2) adjacent wire pairs in cable.

Twisted Pair Cable

It consists of two insulated strands of copper wire that are arranged in a regular spiral pattern.

Phase

It describes the position of the waveform relative to time zero; it is a measurement of the delay of the wave relative to some fixed reference point or another sine wave.

Coating / Buffer

It helps shield the core and cladding from damage.

Half-Duplex Mode

It is a connection wherein data can flow in both directions, but not simultaneous (both at the same time) over a shared physical medium.

Simplex Mode

It is a connection wherein data flows in one (1) direction only (unidirectional). This type is either transmit-only or receive-only.

Full-Duplex Mode

It is a connection wherein data simultaneously flows in both directions (e.g. both users in a telephone conversation can speak and be heard at the same time).

Thin Cable

It is a flexible coaxial cable at about 0.64 centimeters (0.25 inches) thick. It uses British Naval Connector (BNC)-T cable connector attached to the computer's Network Interface Card (NIC).

Ground Wave Propagation Method

It is a method by which radio waves are radiated directly towards the earth's surface.

Sky Wave Propagation Method

It is a method by which radio waves radiate upwards from the transmitting antenna of the earth into a direction towards the ionosphere. It is used for long distance radio telephony and sound broadcasting with a frequency that ranges from 3 MHz to 30 MHz.

Space Wave Propagation Method

It is a method by which radio waves radiation exceeds 30 MHz up to 300 GHz. It is used for sound/television broadcasting for radio relay systems and for various mobile systems that operates in a frequency that ranges from 30 to 300 MHz, 300 MHz to 3 GHz, and 3 to 30 GHz.

Line of Sight Propagation Method

It is a method by which radio waves travel from the transmitting antenna to the receiving antenna. The receiving antenna must be located within the radio horizon of the transmitting antenna. The two (2) antennas mentioned above must "see" each other.

transceiver

It is a portmanteau of "transmitter" and "receiver," meaning it could both transmit and receive signals.

Thick Cable

It is a relatively rigid coaxial cable at about 1.27 centimeters (0.5 inches) in diameter. It uses vampire tap or piercing tap as connectors.

Bluetooth

It is a short-range wireless communication technology that allows devices such as mobile phones, computers, and peripherals to transmit data or voice wirelessly over a short distance.

Parallel Transmission

It is a transmission wherein group of bits is sent simultaneously, but each uses a different channel. It is less reliable because bits tend to muddle up and may arrive out of order.

Serial Transmission

It is a transmission, in which data with each bit lining up in a series as the bits are sent over a single wire at a time.

Analog Wave

It is a wave in which both the amplitude and time continuously varies over their respective intervals that results in a wavy characteristic. Examples of this wave include human voice and music.

Digital Wave

It is a wave with several discrete (jumpy) states, such as high or low, and on or off. It has fixed amplitude but its pulse width and frequency can be changed. An example of this signal is the data stored in the memory of a computer in the form of 0s and 1s.

Antenna

It is also known as "aerial", refers to a metallic structure that acts as a transducer which converts electrical energy to electromagnetic energy (upon transmission of signal) and vice versa (upon reception of signal).

Wall plate

It is used to support two (2) or more couplers.

Omnidirectional Antenna

It issues and receive 360-degree horizontal wireless signals that propagates in all directions.

Directional Antenna

It issues wireless signals along a single direction that employs high frequencies at wider distances.

Fiber Optic Cable

It refers to a bundle of extremely thin and cylindrically shaped glass (or plastic) strands (or fibers) surrounded by a concentric layer of glass (or plastic) coating that is capable of conducting modulated light transmissions.

Shielded Twisted-Pair Cable / STP Cable

It refers to a twisted pair cable that combines the techniques of twisting wires, cancellation, and shielding. Each pair of eight (8) individual copper wires is twisted and then wrapped in a metallic foil.

Unshielded Twisted-Pair Cable / UTP Cable

It refers to a twisted pair cable that contains no shielding. It has eight (8) individual copper wires (covered by an insulating material), in which pairs of it are twisted around each other to form a four-pair color-coded wire medium that are encased/enclosed in a flexible plastic sheath.

RJ-45 connectors

It refers to a twisted pair cabling connection plug.

Amplitude

It refers to a vertical distance from a given point on the wave from the horizontal axis. This is measured in volts, amperes, or watts, depending on the type of signal.

Radio Wave

It refers to a wireless medium that is used for multicast communications and paging systems over long distances. It functions with or without line of sight.

Infrared

It refers to a wireless medium that is used for short-range communication in a closed area using line-of-sight propagation. It is achieved using transmitters/receivers (transceivers) that modulate non-coherent infrared light.

Expandable Patch Panel

It refers to an array of port mounted in the rack shelves.

Cladding

It refers to an outer optical glass or plastic coating that surrounds and traps the light in the core by the principle of total internal reflection.

Jacket

It refers to an outermost layer that protects a buffer or a bundle of buffer-coated fibers against moisture (solvents), abrasion, crushing, and other environmental dangers.

Wave

It refers to disturbances that causes energy to travel through a medium from one location to another.

Wavelength

It refers to the horizontal distance of a wave from a point to the corresponding point on the next wave.

Core

It refers to the innermost section that consists of one (1) or more very thin strands or fibers made of glass or plastic. It allows light to pass through at very high speeds from the point of origin to the destination, with minimal loss in quality or data.

Frequency

It refers to the number of waves made per second or as cycles per second. It is the reciprocal of the period of time to complete one (1) wave cycle.

Coaxial Cable

It refers to two (2) conductors, enclosed by insulating protective coating.

Jack Coupler

It serves as a connector between single or double RJ-45 jacks.

TIA / EIA-568-B

The __________________ standard specifies ten tests that a copper cable must pass if it will be used for modern, high-speed Ethernet LANs.

Acoustic Signals

These are audio or speech signals.

Noise

These are interference or unwanted and undesired form of signal.

Biological Signals

These are signals found in sequence of bases in a gene.

Electrical Signals

These are signals found in voltages and currents in a circuit.

Single-mode, Multimode

These are the 2 Fiber Optic Modes.

Wired, Wireless / Bounded Media, Unbounded Media

These are the 2 Kinds of Networking Media.

Polyvinyl chloride grade, Plenum grade / PVC grade, Plenum grade

These are the 2 choices of coaxial cable grade.

Directional, Omnidirectional

These are the 2 types of Antenna.

Serial, Parallel

These are the 2 types of Network Transmission.

Thin Cable, Thick Cable

These are the 2 types of coaxial cable.

Bandwidth, Transmission Impairments, Interference, Number of Receivers

These are the 4 Network Design Factors.

Core, Cladding, Coating/Buffer, Jacket

These are the 4 Parts of a Fiber Optic Cable.

Dual Shielded, Quad Shielded

These are the two kinds of shielding.

Transmission Impairments

These limit the distance travelled by a signal (e. g. attenuation).

Insertion loss

These measures the amount of energy that is lost as the signal arrives at the receiving end of the cabling link.

Wired / Bounded Media

These networking media use cables and are limited by the physical geography.

Equal-level far-end crosstalk / ELFEXT

This is derived by subtracting the attenuation of the disturbing pair from the Far End Crosstalk (FEXT); this pair induces in an adjacent pair.

Power Sum NEXT / PSNEXT

This is derived from the summation of the individual NEXT, which effects on each pair by the other three (3) pairs.

Wire Map

This is used to identify installation wiring errors; it insures that no open or short circuits exist on the cable and also verifies that all eight (8) wires are connected to the correct pins on both ends of the cable.

Wireless / Unbounded Media

This networking media doesn't use any cables in transmitting data and is not bounded by physical geography.

Signal / Electronics transmitted information

This refers to a detectable physical quantity or impulse by which messages or information can be transmitted/conveyed.

Signal / Means of Communication

This refers to a sign or indication that conveys information about something or that tells someone to do something

Signal / Communicated information

This refers to an event or act, which shows that something exists or that gives information about something.

Period

This refers to the amount of time (expressed in seconds) required to complete one (1) full cycle.

Delay Skew

This refers to the delay difference between the fastest and slowest pairs in a UTP cable.

Cable length

This refers to the physical or sheath length of the cable; it is in contrast to electrical or helical length, which is the length of the copper conductors.

Network Rack

This serves as an extra room for cables where there isn't much floor space.

Crosstalk

This twisted-wire pairs produce a magnetic field cancellation effect, which limits signal degradation caused by interference from nearby twisted pair known as ____________________.