K2 Stuctured cabling and K8 Flashcards
point of demarcation
the point at which the service provider terminates
List three network topologies
Bus
Star
Ring
UTP
Unshielded twisted pair
STP
Shielded twisted-pair
ScTP
Screened twisted-pair
Two types of Coaxial cable
RG-6 limited to 152 m
RG-59 limited to 61 m
What is the max length of horizontal cable?
90m
What is the max length of patch cords or jumpers?
10m
What is the difference between a code and a standard?
Code governs install practices and Standards are guidelines to install practices
Three types of LAN cables
twisted pair, coaxial, fiber-optic
Why is UTP cable twisted?
to shield against electromagnetic interference between wires. the twisting cancels each other out
what is the pulling tension of Cat 5 horizontal distribution cable?
25 lbs
Describe Wire Mapping
this test confirms whether or not there is proper connection of all four pairs of UTP cabling
Describe Attenuation test
is a measure of the signal loss from one end of the link to the other. Is expressed in dB: the lower the number the better
Describe Crosstalk
the unplanned transfer of information from one cct to another cct
what does FEXT mean
Far-end crosstalk
what does NEXT mean
near-end crosstalk
what does ANEXT
alien crosstalk
Return Loss
a ratio in dB of the outgoing signal’s power compared to the power of the signal reflected back
ACR attenuation to crosstalk ratio
measure of how much more signal than noise exists in the link
Decibel
the bel is a measure of analogue signal strength
Noise
an unwanted electrical activity that interferes with the desired signal transmission
basic link
permanent portion of the cable from the patch panel to the work-area outlet
two possible causes of attenuation
high temp, too long cable
List three actions that can reduce noise
maintain cable separation
no split pairs
maintain cable twisting
Four components of a fibre-optic installation
transmitter
fibre-optic cable
optical connectors
receiver
VIsible light is from
380 to 760 nm
Advantages of fibre-optic
Wide bandwidth Low loss Electro-magnetic immunity Light weight Small size More safe
List the parts of a fibre-optic cable
core cladding primary coating buffer strength members outer jacket
CEC list what three types of fibre-optic cables?
nonconductive
conductive
hybrid
What type of light is used in fibre-optic cable
infared light
As the Hz of a waveform increases its wavelength
decreases
List five purposes of security systems
Deterrence Prevention Detection Response Apprehension
onion skin principle
provides layers of protection
List the three layers of protection
Perimeter
Space
Spot
The three main cct in a basic alarm system
Detection
Control
Output
What does a PIR detector detect
changes in the levels of infrared energy
