CTS Questions and Answers with
Complete Solutions
• 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.
Complete Solutions
• 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.
