Twisted Pair Cabling Flashcards
Cross Over Cable
For connecting similar devices to each other
Horizontal Cabling
Permanent network cabling within a building Extends from telecommunications closet into LAN work area
Terminated
Where cable connects to wall jack, patch panel, or RJ-45 connection
Overall length limiation of UTP cable from TC to networking device?
100 meters
STP
Shielded Twisted-Pair Cable Wire screen / metal foil shield placed around cable to reduce EMI
FastEthernet
100 Mbps
Recommended cable for LAN work areas
CAT6 UTP
Straight-through Cable
Attenuation
Insertion Loss
Amount of loss in signal strength as it propogates down the wire.
Crosstalk
Voltage induced in adjacent wires.
Hearing another conversation when you are on the phone
NEXT
Near-end Crosstalk
Measure of level of crosstalk within the cable
PSNEXT
Power Sum NEXT
Measure of total crosstalk of all cable pairs
ELFEXT
Equal Level FEXT
Attenuation value subtracted from FEXT (Far-end crosstalk) loss.
PSELFEXT
Power Sum ELFEXT
Combined ELFEXT of all four wire pairs
ACR
Signal level from transmitter at far end to crosstalk at near end
PSACR
Power Sum ACR
Difference between PSNEXT and attenuation for all four wire pairs
Return Loss
Ratio of power transmitted into cable and amount of power returned
Propogation Delay
Measure of time it takes for a signal to propagate from one end of a cable to the other
Delay Skew
Difference in arrival time between fastest and lowest signal in a UTP wire pair
AXT
Alien Crosstalk
Unwanted signal coupling from one permanent link to another
TCL
Transverse Conversion Loss
Also called LCL (Longitudinal Conversion Loss)
Measured by applying common-mode signal to input and measuring differential signal level at output.
ELTCTL
Equal level Transverse Conversion Transfer Loss
Difference between Transfer Conversion Transfer Loss and differential mode insertion loss of the pair being measured.
