Podcast
Questions and Answers
Baseband modulation sends the 'bare' signal.
Baseband modulation sends the 'bare' signal.
True
Carrier modulation uses the signal to modulate a higher frequency signal (carrier).
Carrier modulation uses the signal to modulate a higher frequency signal (carrier).
True
Amplitude Modulation (AM) changes the strength of the signal.
Amplitude Modulation (AM) changes the strength of the signal.
True
Frequency Modulation (FM) changes the frequency.
Frequency Modulation (FM) changes the frequency.
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Phase Modulation (PM) changes the phase of the signal.
Phase Modulation (PM) changes the phase of the signal.
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The Nyquist Limit states that a noiseless channel of width H can transmit a binary signal at a rate 2 x H.
The Nyquist Limit states that a noiseless channel of width H can transmit a binary signal at a rate 2 x H.
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Frequency Division Multiplexing (FDM) allows multiple users to send data at the same time using different carrier frequencies.
Frequency Division Multiplexing (FDM) allows multiple users to send data at the same time using different carrier frequencies.
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Time Division Multiplexing (TDM) allows multiple users to send data at different times using the same carrier frequency.
Time Division Multiplexing (TDM) allows multiple users to send data at different times using the same carrier frequency.
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Fiber optic cables can transmit data at speeds up to 10 Gbps over long distances.
Fiber optic cables can transmit data at speeds up to 10 Gbps over long distances.
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Multimode fiber can carry multiple modes of light propagation and is subject to mode dispersion.
Multimode fiber can carry multiple modes of light propagation and is subject to mode dispersion.
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Single mode fiber can carry a single mode of light propagation and is not subject to mode dispersion.
Single mode fiber can carry a single mode of light propagation and is not subject to mode dispersion.
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Wavelength Division Multiplexing (WDM) allows multiple wavelengths to be sent through the same fiber and each wavelength can carry a separate signal.
Wavelength Division Multiplexing (WDM) allows multiple wavelengths to be sent through the same fiber and each wavelength can carry a separate signal.
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True or false: The Nyquist Limit states that a noiseless channel of width H can at most transmit a binary signal at a rate 2 x H.
True or false: The Nyquist Limit states that a noiseless channel of width H can at most transmit a binary signal at a rate 2 x H.
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True or false: Shannon's theorem states that the maximum capacity of a noisy channel is equal to the channel bandwidth multiplied by the logarithm (base 2) of 1 + the signal to noise (power) ratio.
True or false: Shannon's theorem states that the maximum capacity of a noisy channel is equal to the channel bandwidth multiplied by the logarithm (base 2) of 1 + the signal to noise (power) ratio.
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True or false: The upper limit on capacity for a local loop bandwidth of 3200 Hz and a typical S/N ratio of 1000 (30db) is 31.895 kbits/s.
True or false: The upper limit on capacity for a local loop bandwidth of 3200 Hz and a typical S/N ratio of 1000 (30db) is 31.895 kbits/s.
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True or false: The tradeoff between data rate and distance is affected by noise, attenuation, and dispersion.
True or false: The tradeoff between data rate and distance is affected by noise, attenuation, and dispersion.
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True or false: Multiple channels can coexist if they transmit at a different frequency, or at a different time, or in a different part of the space.
True or false: Multiple channels can coexist if they transmit at a different frequency, or at a different time, or in a different part of the space.
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True or false: Time Division Multiplexing requires spectrum proportional to aggregate bandwidth.
True or false: Time Division Multiplexing requires spectrum proportional to aggregate bandwidth.
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True or false: The physical layer is responsible for transferring information in computer networks?
True or false: The physical layer is responsible for transferring information in computer networks?
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True or false: The datalink layer is responsible for error coding in computer networks?
True or false: The datalink layer is responsible for error coding in computer networks?
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True or false: Switched networks are a type of broadcast network?
True or false: Switched networks are a type of broadcast network?
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True or false: Sound waves can be information carriers in computer networks?
True or false: Sound waves can be information carriers in computer networks?
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True or false: Quantum states can be information carriers in computer networks?
True or false: Quantum states can be information carriers in computer networks?
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True or false: Ink and paper can be information carriers in computer networks?
True or false: Ink and paper can be information carriers in computer networks?
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The physical properties of media limit the bandwidth and distance of networks.
The physical properties of media limit the bandwidth and distance of networks.
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Aggressive encoding techniques make the signal more sensitive to noise.
Aggressive encoding techniques make the signal more sensitive to noise.
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Nyquist's formula, C = B x log2(1 + S/N), gives an idealized throughput.
Nyquist's formula, C = B x log2(1 + S/N), gives an idealized throughput.
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Low bandwidth channels require simpler encoding techniques.
Low bandwidth channels require simpler encoding techniques.
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Multiple users can be supported using space, time, or frequency division multiplexing.
Multiple users can be supported using space, time, or frequency division multiplexing.
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Copper, optical, and wireless are examples of different transmission media.
Copper, optical, and wireless are examples of different transmission media.
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True or false: In computer networks, information carriers can only be electrical or optical signals?
True or false: In computer networks, information carriers can only be electrical or optical signals?
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True or false: EM waves can be information carriers in computer networks?
True or false: EM waves can be information carriers in computer networks?
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True or false: Proteins can be information carriers in computer networks?
True or false: Proteins can be information carriers in computer networks?
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True or false: Ink and paper cannot be information carriers in computer networks?
True or false: Ink and paper cannot be information carriers in computer networks?
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True or false: Sound waves cannot be information carriers in computer networks?
True or false: Sound waves cannot be information carriers in computer networks?
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True or false: Quantum states can be information carriers in computer networks?
True or false: Quantum states can be information carriers in computer networks?
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True or false: Modulation is the process of changing a signal to convey information, such as volume, pitch, or timing?
True or false: Modulation is the process of changing a signal to convey information, such as volume, pitch, or timing?
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True or false: Amplitude Modulation (AM) changes the frequency of the signal?
True or false: Amplitude Modulation (AM) changes the frequency of the signal?
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True or false: Frequency Modulation (FM) changes the strength of the signal?
True or false: Frequency Modulation (FM) changes the strength of the signal?
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True or false: Phase Modulation (PM) changes the phase of the signal?
True or false: Phase Modulation (PM) changes the phase of the signal?
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True or false: Baseband modulation sends the 'bare' signal?
True or false: Baseband modulation sends the 'bare' signal?
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True or false: Carrier modulation uses the signal to modulate a higher frequency signal (carrier)?
True or false: Carrier modulation uses the signal to modulate a higher frequency signal (carrier)?
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True or false: Bandwidth and distance of networks is not limited by physical properties of media?
True or false: Bandwidth and distance of networks is not limited by physical properties of media?
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True or false: Nyquist gives an idealized throughput and can do much better with better encoding?
True or false: Nyquist gives an idealized throughput and can do much better with better encoding?
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True or false: Low bandwidth channels require sophisticated encoding and multiple bits per wavelength?
True or false: Low bandwidth channels require sophisticated encoding and multiple bits per wavelength?
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True or false: Shannon's theorem states that C = B x log2(1 + S/N)?
True or false: Shannon's theorem states that C = B x log2(1 + S/N)?
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True or false: Multiple users can be supported using time division multiplexing?
True or false: Multiple users can be supported using time division multiplexing?
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True or false: Copper, optical, and wireless are examples of different transmission media?
True or false: Copper, optical, and wireless are examples of different transmission media?
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True or false: Frequency Division Multiplexing (FDM) allows different users to use different parts of the frequency spectrum.
True or false: Frequency Division Multiplexing (FDM) allows different users to use different parts of the frequency spectrum.
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True or false: Time Division Multiplexing (TDM) allows different users to send data at different times.
True or false: Time Division Multiplexing (TDM) allows different users to send data at different times.
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True or false: Single mode fiber can carry multiple modes of light propagation and is subject to mode dispersion.
True or false: Single mode fiber can carry multiple modes of light propagation and is subject to mode dispersion.
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True or false: Copper twisted pair cables can transmit data at speeds up to 100 Mbit/s up to 100 m.
True or false: Copper twisted pair cables can transmit data at speeds up to 100 Mbit/s up to 100 m.
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True or false: Wavelength Division Multiplexing (WDM) allows multiple wavelengths to be sent through the same fiber and each wavelength can carry a separate signal.
True or false: Wavelength Division Multiplexing (WDM) allows multiple wavelengths to be sent through the same fiber and each wavelength can carry a separate signal.
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True or false: Fiber optic cables can transmit data at speeds up to 10 Gbps over long distances.
True or false: Fiber optic cables can transmit data at speeds up to 10 Gbps over long distances.
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True or false: The Nyquist Limit states that a noiseless channel of width H can transmit a binary signal at a rate 2 x H.
True or false: The Nyquist Limit states that a noiseless channel of width H can transmit a binary signal at a rate 2 x H.
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True or false: Shannon's theorem states that the maximum capacity of a noisy channel is equal to the channel bandwidth multiplied by the logarithm (base 2) of 1 + the signal to noise (power) ratio.
True or false: Shannon's theorem states that the maximum capacity of a noisy channel is equal to the channel bandwidth multiplied by the logarithm (base 2) of 1 + the signal to noise (power) ratio.
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True or false: Time Division Multiplexing requires spectrum proportional to aggregate bandwidth.
True or false: Time Division Multiplexing requires spectrum proportional to aggregate bandwidth.
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True or false: Multiple channels can coexist if they transmit at a different frequency, or at a different time, or in a different part of the space.
True or false: Multiple channels can coexist if they transmit at a different frequency, or at a different time, or in a different part of the space.
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True or false: The tradeoff between data rate and distance is affected by noise, attenuation, and dispersion.
True or false: The tradeoff between data rate and distance is affected by noise, attenuation, and dispersion.
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True or false: The upper limit on capacity for a local loop bandwidth of 3200 Hz and a typical S/N ratio of 1000 (30db) is 31.895 kbits/s.
True or false: The upper limit on capacity for a local loop bandwidth of 3200 Hz and a typical S/N ratio of 1000 (30db) is 31.895 kbits/s.
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True or false: The physical layer is responsible for transferring information in computer networks?
True or false: The physical layer is responsible for transferring information in computer networks?
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True or false: Copper, optical, and wireless are examples of different transmission media?
True or false: Copper, optical, and wireless are examples of different transmission media?
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True or false: Ink and paper can be information carriers in computer networks?
True or false: Ink and paper can be information carriers in computer networks?
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True or false: Quantum states can be information carriers in computer networks?
True or false: Quantum states can be information carriers in computer networks?
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True or false: Sound waves can be information carriers in computer networks?
True or false: Sound waves can be information carriers in computer networks?
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True or false: EM waves can be information carriers in computer networks?
True or false: EM waves can be information carriers in computer networks?
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True or false: Modulation is the process of changing a signal to convey information, such as volume, pitch, or timing?
True or false: Modulation is the process of changing a signal to convey information, such as volume, pitch, or timing?
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True or false: Baseband modulation sends the 'bare' signal without using a carrier frequency?
True or false: Baseband modulation sends the 'bare' signal without using a carrier frequency?
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True or false: Frequency modulation (FM) changes the amplitude of the signal to convey information?
True or false: Frequency modulation (FM) changes the amplitude of the signal to convey information?
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True or false: Phase modulation (PM) changes the phase of the signal to convey information?
True or false: Phase modulation (PM) changes the phase of the signal to convey information?
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True or false: Carrier modulation uses the signal to modulate a higher frequency carrier signal?
True or false: Carrier modulation uses the signal to modulate a higher frequency carrier signal?
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True or false: The Nyquist Limit states that a noiseless channel of width H can transmit a binary signal at a maximum rate of 2H?
True or false: The Nyquist Limit states that a noiseless channel of width H can transmit a binary signal at a maximum rate of 2H?
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True or false: Frequency Division Multiplexing (FDM) allows multiple users to use different parts of the frequency spectrum?
True or false: Frequency Division Multiplexing (FDM) allows multiple users to use different parts of the frequency spectrum?
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True or false: Time Division Multiplexing (TDM) requires spectrum proportional to aggregate bandwidth?
True or false: Time Division Multiplexing (TDM) requires spectrum proportional to aggregate bandwidth?
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True or false: Multimode fiber can carry multiple modes of light propagation and is subject to mode dispersion?
True or false: Multimode fiber can carry multiple modes of light propagation and is subject to mode dispersion?
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True or false: Single mode fiber can carry a single mode of light propagation and is not subject to mode dispersion?
True or false: Single mode fiber can carry a single mode of light propagation and is not subject to mode dispersion?
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True or false: Aggressive encoding techniques make the signal more sensitive to noise?
True or false: Aggressive encoding techniques make the signal more sensitive to noise?
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True or false: Fiber optic cables can transmit data at speeds up to 10 Gbps over long distances?
True or false: Fiber optic cables can transmit data at speeds up to 10 Gbps over long distances?
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True or false: The Nyquist Limit states that a noiseless channel of width H can at most transmit a binary signal at a rate 2 x H.
True or false: The Nyquist Limit states that a noiseless channel of width H can at most transmit a binary signal at a rate 2 x H.
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True or false: Shannon's theorem states that the maximum capacity of a noisy channel is equal to the channel bandwidth multiplied by the logarithm (base 2) of 1 + the signal to noise (power) ratio.
True or false: Shannon's theorem states that the maximum capacity of a noisy channel is equal to the channel bandwidth multiplied by the logarithm (base 2) of 1 + the signal to noise (power) ratio.
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True or false: Copper, optical, and wireless are examples of different transmission media?
True or false: Copper, optical, and wireless are examples of different transmission media?
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True or false: Quantum states can be information carriers in computer networks?
True or false: Quantum states can be information carriers in computer networks?
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True or false: Time Division Multiplexing requires spectrum proportional to aggregate bandwidth.
True or false: Time Division Multiplexing requires spectrum proportional to aggregate bandwidth.
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True or false: Multiple channels can coexist if they transmit at a different frequency, or at a different time, or in a different part of the space.
True or false: Multiple channels can coexist if they transmit at a different frequency, or at a different time, or in a different part of the space.
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True or false: Aggressive encoding techniques make the signal less sensitive to noise?
True or false: Aggressive encoding techniques make the signal less sensitive to noise?
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True or false: The Nyquist Limit states that a noiseless channel of width H can transmit a binary signal at a rate 2 x H?
True or false: The Nyquist Limit states that a noiseless channel of width H can transmit a binary signal at a rate 2 x H?
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True or false: Shannon's theorem states that the maximum capacity of a noisy channel is equal to the channel bandwidth multiplied by the logarithm (base 2) of 1 + the signal to noise (power) ratio?
True or false: Shannon's theorem states that the maximum capacity of a noisy channel is equal to the channel bandwidth multiplied by the logarithm (base 2) of 1 + the signal to noise (power) ratio?
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True or false: Low bandwidth channels require sophisticated encoding and multiple bits per wavelength?
True or false: Low bandwidth channels require sophisticated encoding and multiple bits per wavelength?
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True or false: Single mode fiber can carry multiple modes of light propagation and is subject to mode dispersion?
True or false: Single mode fiber can carry multiple modes of light propagation and is subject to mode dispersion?
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True or false: The tradeoff between data rate and distance is affected by noise, attenuation, and dispersion?
True or false: The tradeoff between data rate and distance is affected by noise, attenuation, and dispersion?
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True or false: The physical layer places constraints on what the network infrastructure can deliver.
True or false: The physical layer places constraints on what the network infrastructure can deliver.
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True or false: Baseband modulation sends the 'bare' signal.
True or false: Baseband modulation sends the 'bare' signal.
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True or false: The Nyquist Limit states that a noiseless channel of width H can transmit a binary signal at a rate 2 x H.
True or false: The Nyquist Limit states that a noiseless channel of width H can transmit a binary signal at a rate 2 x H.
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True or false: Amplitude Modulation (AM) changes the strength of the signal.
True or false: Amplitude Modulation (AM) changes the strength of the signal.
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True or false: Frequency Modulation (FM) changes the frequency.
True or false: Frequency Modulation (FM) changes the frequency.
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True or false: Phase Modulation (PM) changes the phase of the signal to convey information.
True or false: Phase Modulation (PM) changes the phase of the signal to convey information.
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True or false: The physical layer is responsible for transferring information using electrical signals, optical signals, and EM waves?
True or false: The physical layer is responsible for transferring information using electrical signals, optical signals, and EM waves?
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True or false: Information carriers in computer networks can also be sound waves, quantum states, proteins, and ink & paper?
True or false: Information carriers in computer networks can also be sound waves, quantum states, proteins, and ink & paper?
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True or false: The datalink layer is responsible for framing, error coding, and switched networks?
True or false: The datalink layer is responsible for framing, error coding, and switched networks?
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True or false: Broadcast networks and home networking are topics covered in the physical layer?
True or false: Broadcast networks and home networking are topics covered in the physical layer?
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True or false: Amplitude modulation (AM) changes the strength of the signal?
True or false: Amplitude modulation (AM) changes the strength of the signal?
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True or false: Baseband modulation sends the 'bare' signal?
True or false: Baseband modulation sends the 'bare' signal?
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True or false: Nyquist's formula, C = B x log2(1 + S/N), gives an idealized throughput?
True or false: Nyquist's formula, C = B x log2(1 + S/N), gives an idealized throughput?
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True or false: The physical properties of media limit the bandwidth and distance of networks?
True or false: The physical properties of media limit the bandwidth and distance of networks?
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True or false: Low bandwidth channels require sophisticated encoding and multiple bits per wavelength?
True or false: Low bandwidth channels require sophisticated encoding and multiple bits per wavelength?
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True or false: Aggressive encoding techniques make the signal less sensitive to noise?
True or false: Aggressive encoding techniques make the signal less sensitive to noise?
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True or false: Modulation is the process of changing a signal to convey information, such as volume, pitch, or timing?
True or false: Modulation is the process of changing a signal to convey information, such as volume, pitch, or timing?
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True or false: Baseband modulation sends the 'bare' signal without using a carrier frequency?
True or false: Baseband modulation sends the 'bare' signal without using a carrier frequency?
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True or false: Aggressive encoding techniques make the signal more sensitive to noise?
True or false: Aggressive encoding techniques make the signal more sensitive to noise?
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True or false: Nyquist formula gives the idealized throughput of a channel?
True or false: Nyquist formula gives the idealized throughput of a channel?
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True or false: Shannon's formula calculates the maximum capacity of a noisy channel?
True or false: Shannon's formula calculates the maximum capacity of a noisy channel?
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True or false: Multiple users can be supported using time division multiplexing?
True or false: Multiple users can be supported using time division multiplexing?
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True or false: Copper, optical, and wireless are examples of different transmission media?
True or false: Copper, optical, and wireless are examples of different transmission media?
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True or false: The physical layer is responsible for transferring information in computer networks?
True or false: The physical layer is responsible for transferring information in computer networks?
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True or false: Frequency Division Multiplexing (FDM) allows different users to use different parts of the frequency spectrum?
True or false: Frequency Division Multiplexing (FDM) allows different users to use different parts of the frequency spectrum?
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True or false: Multimode fiber can carry multiple modes of light propagation and is subject to mode dispersion?
True or false: Multimode fiber can carry multiple modes of light propagation and is subject to mode dispersion?
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True or false: Time Division Multiplexing (TDM) requires spectrum proportional to aggregate bandwidth?
True or false: Time Division Multiplexing (TDM) requires spectrum proportional to aggregate bandwidth?
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True or false: Wavelength Division Multiplexing (WDM) allows multiple wavelengths to be sent through the same fiber and each wavelength can carry a separate signal?
True or false: Wavelength Division Multiplexing (WDM) allows multiple wavelengths to be sent through the same fiber and each wavelength can carry a separate signal?
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True or false: Single mode fiber can carry a single mode of light propagation and is not subject to mode dispersion?
True or false: Single mode fiber can carry a single mode of light propagation and is not subject to mode dispersion?
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True or false: The tradeoff between data rate and distance is affected by noise, attenuation, and dispersion?
True or false: The tradeoff between data rate and distance is affected by noise, attenuation, and dispersion?
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Study Notes
Physical Layer
- The physical layer is responsible for transferring information through physical signals.
- Signals can be transmitted through electrical signals (on a wire), optical signals (in a fiber), or electromagnetic waves.
Types of Signals
- Digital Signals: Represented by discrete values (0s and 1s).
- Analog Signals: Represented by continuous values.
Modulation
- Modulation: Changing a signal to convey information.
-
Modulation Techniques:
- Amplitude Modulation (AM): Change the strength of the signal.
- Frequency Modulation (FM): Change the frequency of the signal.
- Phase Modulation (PM): Change the phase of the signal.
Bandwidth Limitations
- Bandwidth: The range of frequencies in which a signal is transmitted.
- Nyquist Limit: The maximum rate at which a noiseless channel can transmit a binary signal (2 x H, where H is the bandwidth).
Frequency Domain
- Frequency Domain: A signal can be represented as a sum of sine waves of different strengths.
- Energy: The strength of a signal at a certain frequency.
Multiplexing
- Multiplexing: Combining multiple signals into a single signal.
-
Types of Multiplexing:
- Time Division Multiplexing (TDM): Multiple signals transmitted at different times.
- Frequency Division Multiplexing (FDM): Multiple signals transmitted at different frequencies.
Transmission Media
-
Copper Wire:
- UTP (Unshielded Twisted Pair): Twisted pair of copper wires.
- Coaxial cables.
-
Fiber Optics:
- Multimode fiber: Carries multiple modes (62.5 or 50 micron core).
- Single-mode fiber: Carries a single mode (8-10 micron core).
- Wireless: Radio waves transmitted through the air.
Channel Capacity
- Shannon's Theorem: The maximum channel capacity (C) is equal to the bandwidth (B) times the logarithm of (1 + signal-to-noise ratio) (S/N).
- Channel Capacity Formula: C = B x log2(1 + S/N).
Important Concepts
- Attenuation: Signal strength decreases with distance.
- Noise: Random energy added to the signal.
- Dispersion: Signal distortion due to differing propagation speeds.
- Regeneration: Electronic repeaters can amplify and retransmit the signal to extend distance.
- Amplification: Optical amplifiers can amplify the signal to extend distance.### Physical Layer
- Channel Capacity: The maximum amount of information that can be transmitted through a communication channel per unit time.
- Nyquist Limit: A noiseless channel of width H can transmit a binary signal at a rate of 2 x H. Assumes binary amplitude encoding.
Modulation
- Baseband Modulation: Sending the "bare" signal.
- Carrier Modulation: Using the signal to modulate a higher frequency carrier signal.
-
Types of Modulation:
- Amplitude Modulation (AM): Changing the strength of the signal.
- Frequency Modulation (FM): Changing the frequency of the signal.
- Phase Modulation (PM): Changing the phase of the signal.
Bandwidth Limitations
- Bandwidth: The width of the frequency range in which the Fourier transform of the signal is nonzero.
- Frequency Domain: A signal can be viewed as a sum of sine waves of different strengths, corresponding to energy at a certain frequency.
- Shannon's Theorem: C = B x log2(1 + S/N), where C is the maximum capacity, B is the channel bandwidth, and S/N is the signal to noise ratio.
Transmission Channel Considerations
- Noise: "Random" energy added to the signal.
- Attenuation: Energy in the signal leaks away.
- Dispersion: Attenuation and propagation speed are frequency dependent, changing the signal shape.
- Tradeoff between Data Rate and Distance: Effects of noise, attenuation, and dispersion become worse with distance.
Multiplexing
- Frequency Division Multiplexing (FDM): Different users use different parts of the frequency spectrum.
- Time Division Multiplexing (TDM): Different users use the wire at different points in time.
- Media Access Control (MAC): Who gets to send when.
Media
-
Copper Wire:
- Unshielded twisted pair (UTP) to avoid antenna effect.
- Category 3 (voice grade) and category 5.
- Cost: ~ 10 cents/foot.
-
Fiber:
- Multimode fiber with a 62.5 or 50 micron core.
- Single mode fiber with a 8 micron core.
- Typical limits: 1 Gbps at 100m, 10 Gbps at 60 km or more.
Wireless Technologies
- Limitations: High attenuation, noise, and interference.
- Use MAC and other rules to limit interference:
- Aggressive encoding techniques to make signal less sensitive to noise:### Physical Layer Overview
- The physical layer is concerned with the transmission of information over a physical medium.
- The physical layer is the lowest layer of the OSI model.
Modulation
- Modulation is the process of changing a signal to convey information.
- Types of modulation:
- Amplitude Modulation (AM): change the strength of the signal.
- Frequency Modulation (FM): change the frequency of the signal.
- Phase Modulation (PM): change the phase of the signal.
Bandwidth Limitations
- The Nyquist Limit states that a noiseless channel of width H can at most transmit a binary signal at a rate 2 x H.
- The Shannon-Hartley theorem states that the maximum capacity of a channel is C = B x log2(1 + S/N), where C is the maximum capacity, B is the channel bandwidth, and S/N is the signal-to-noise ratio.
Frequency Spectrum and Its Use
- The frequency spectrum is the range of frequencies that a signal can occupy.
- Different users can be multiplexed using different frequencies (Frequency Division Multiplexing, FDM).
- Different users can be multiplexed using different times (Time Division Multiplexing, TDM).
Media: Copper, Fiber, Optical, Wireless
- Copper wire:
- Unshielded twisted pair (UTP) is commonly used.
- Coax cables are used for high-speed applications.
- Fiber:
- Multimode fiber has a larger core diameter and is used for shorter distances.
- Single mode fiber has a smaller core diameter and is used for longer distances.
- Fiber types are classified by their core diameter and wavelength.
- Optical:
- Light transmission in fiber uses LEDs or lasers.
- Wireless:
- Radio waves are used to transmit information.
Transferring Information
- Information transfer is a physical process that involves the transmission of signals over a medium.
- Signals can be analog or digital.
- Digital signals are used in computer networks.
Multiplexing
- Multiplexing is the process of combining multiple signals over a single medium.
- FDM and TDM are two types of multiplexing.
- FDM is used in radio broadcasting and TDM is used in computer networks.
Copper Wire
- Copper wire is a common medium used for data transmission.
- UTP is widely used due to its low cost and ease of installation.
- Coax cables are used for high-speed applications.
Fiber Optics
- Fiber optics use light to transmit information.
- Fiber types are classified by their core diameter and wavelength.
- Single mode fiber has a smaller core diameter and is used for longer distances.
Increasing Distance
- Even with single mode fiber, there is a distance limit.
- Regeneration and amplification are used to increase the distance.
- Electronic repeaters and erbium-doped fiber amplifiers are used to amplify the signal.
Physical Layer Properties
- Bandwidth and distance of networks are limited by physical properties of media.
- Attenuation, noise, and dispersion affect the transmission of signals.
- Network properties are determined by the transmission medium and transmit/receive hardware.
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Description
Quiz: The Nyquist Limit in Binary Amplitude Encoding Test your knowledge about the Nyquist limit and binary amplitude encoding with this quiz. Learn about the maximum data transmission rate in a noiseless channel and how to calculate it using the Nyquist formula. Discover the relationship between channel width and data transmission speed. Challenge yourself and see how well you understand this important concept in communication systems.