CTS Top Exam Questions and answers,
100% Accurate. Verified.
• Analog to Digital Conversion: Sampling Rate - ✔✔-how many times a digital sample is taken of the
analog sample, per second
Ex. CD Sampling rate = 44.1kHz
Called Pulse Code Modulation (PCM)
Determines digital signal's accuracy
Nyquist-Shannon Sampling Thm - ✔✔-• Analog sig must be encoded at rate 2X or more than highest
freq. of sample
• Human hearing is up to 20kHz -> digital audio should be at least 40 kHz
o Bit depth - ✔✔-Number of bits used to describe a sampled voltage level -> "quantization"
Assigns quantity to the signal being measured
Greater bit depth = more accurate rep of signal
• i.e. if sig has on bit -> 0 or 1-> describes only two states, on or off
• 2 bits= 4 states
• CD has 16 bits -> 216
In video, bit depth is how many shades can be described
o Bit Rate - ✔✔-Measures quantity of info over time in a dig. Signal stream
Bits per second bps
Higher bps = higher quality
o Compression - ✔✔-Reducing file size to smaller, more manageable
Remove unnecessary info
In text files, spaces compressed without affecting words
,In videos, use codec for transfer
• Usually 5:1 compression
o Codec - ✔✔-Converts analog to dig for both audio and video
Conserves bandwidth
o 2 elements of digital file: - ✔✔-Container - structure of file where data is stored
• Defines how data is arranged to inc. performance when codecs used
• i.e. WMV
Codec
o Lossless compression - ✔✔-never loses quality
Larger file sizes
i.e. winzip
o Lossy compression - ✔✔-approx. of original data, eliminates unnecessary or redundant info
Multiple reopening with degrade file
o Noise - ✔✔-Analog
• Need amplifiers for analog signals cause losses
• Amplifiers make noise worse
• Degradation
Digital
• Not affected
• Discerning circuitry helps rebuild
o Nodes - ✔✔-devices sharing the data, sends or receives
,o Connections - ✔✔-- physical means by which data travels between nodes
o NIC - ✔✔-any device that connects to network must have one
Interface that allows you to connect to network
Has own MAC
o MAC - ✔✔-hardware address
ID for the network
48 bit number, 6 groups of 2 hexidecimal numbers
• First part manufacturer, second is serial #
o Switch - ✔✔-provides phys connection btwn multiple devices
Stores each MAC address
Communication w/ parts via Ethernet
Either managed or unmanaged
Managed is configurable -> VLANs, monitor traffic, etc.
o Router - ✔✔-forwards data between devices not directly connected
Border between Lan and Wan
Uses IP address
o Gateway - ✔✔-router that connects private to public IPs
Translates between protocols
• Private uses baseband, public uses broadband
o Server - ✔✔-provides a service to dependent nodes
can be a program, computer hardware
often hosted on several computers
, thin server - provides one service
• Network Connections
o 3 Most common - ✔✔-Copper - uses Voltage
Optical Fiber
Wifi
Copper - uses Voltage - ✔✔-• Twisted pair
o "cats"
o Under Ethernet standards
o Cat 5e - ✔✔-designation for 100 Ohm unshielded twisted pair cables
100 MHz - 100 Mbps and 1Gbps
Adds specs for far end crosstalk
o Cat 6 - ✔✔-more twists per inch
250 MHz - 100 Mbps and 1Gbps
Higher speeds -> higher freq. with tiny wavelengths
Susceptible to noise
Need to be shielded
o Cat6a - ✔✔-augmented form of Cat 6
Capable of 10Gbps
Very high freq
Account for Alien Crosstalk (AXT)
• Unknown noise that can't be cancelled out by equipment
UTP - protected from AXT, can't be more than 55'
STP - better protected, can go longer
100% Accurate. Verified.
• Analog to Digital Conversion: Sampling Rate - ✔✔-how many times a digital sample is taken of the
analog sample, per second
Ex. CD Sampling rate = 44.1kHz
Called Pulse Code Modulation (PCM)
Determines digital signal's accuracy
Nyquist-Shannon Sampling Thm - ✔✔-• Analog sig must be encoded at rate 2X or more than highest
freq. of sample
• Human hearing is up to 20kHz -> digital audio should be at least 40 kHz
o Bit depth - ✔✔-Number of bits used to describe a sampled voltage level -> "quantization"
Assigns quantity to the signal being measured
Greater bit depth = more accurate rep of signal
• i.e. if sig has on bit -> 0 or 1-> describes only two states, on or off
• 2 bits= 4 states
• CD has 16 bits -> 216
In video, bit depth is how many shades can be described
o Bit Rate - ✔✔-Measures quantity of info over time in a dig. Signal stream
Bits per second bps
Higher bps = higher quality
o Compression - ✔✔-Reducing file size to smaller, more manageable
Remove unnecessary info
In text files, spaces compressed without affecting words
,In videos, use codec for transfer
• Usually 5:1 compression
o Codec - ✔✔-Converts analog to dig for both audio and video
Conserves bandwidth
o 2 elements of digital file: - ✔✔-Container - structure of file where data is stored
• Defines how data is arranged to inc. performance when codecs used
• i.e. WMV
Codec
o Lossless compression - ✔✔-never loses quality
Larger file sizes
i.e. winzip
o Lossy compression - ✔✔-approx. of original data, eliminates unnecessary or redundant info
Multiple reopening with degrade file
o Noise - ✔✔-Analog
• Need amplifiers for analog signals cause losses
• Amplifiers make noise worse
• Degradation
Digital
• Not affected
• Discerning circuitry helps rebuild
o Nodes - ✔✔-devices sharing the data, sends or receives
,o Connections - ✔✔-- physical means by which data travels between nodes
o NIC - ✔✔-any device that connects to network must have one
Interface that allows you to connect to network
Has own MAC
o MAC - ✔✔-hardware address
ID for the network
48 bit number, 6 groups of 2 hexidecimal numbers
• First part manufacturer, second is serial #
o Switch - ✔✔-provides phys connection btwn multiple devices
Stores each MAC address
Communication w/ parts via Ethernet
Either managed or unmanaged
Managed is configurable -> VLANs, monitor traffic, etc.
o Router - ✔✔-forwards data between devices not directly connected
Border between Lan and Wan
Uses IP address
o Gateway - ✔✔-router that connects private to public IPs
Translates between protocols
• Private uses baseband, public uses broadband
o Server - ✔✔-provides a service to dependent nodes
can be a program, computer hardware
often hosted on several computers
, thin server - provides one service
• Network Connections
o 3 Most common - ✔✔-Copper - uses Voltage
Optical Fiber
Wifi
Copper - uses Voltage - ✔✔-• Twisted pair
o "cats"
o Under Ethernet standards
o Cat 5e - ✔✔-designation for 100 Ohm unshielded twisted pair cables
100 MHz - 100 Mbps and 1Gbps
Adds specs for far end crosstalk
o Cat 6 - ✔✔-more twists per inch
250 MHz - 100 Mbps and 1Gbps
Higher speeds -> higher freq. with tiny wavelengths
Susceptible to noise
Need to be shielded
o Cat6a - ✔✔-augmented form of Cat 6
Capable of 10Gbps
Very high freq
Account for Alien Crosstalk (AXT)
• Unknown noise that can't be cancelled out by equipment
UTP - protected from AXT, can't be more than 55'
STP - better protected, can go longer
