CNIT 240/344 Final Exam
Open System Interconnection (OSI) - Answer-7 layers for open interconnection
between any two systems regardless of vendor
OSI rules - Answer-layers can only communicate with adjacent layers
OSI benefits - Answer-break network communication into more manageable parts
and vendor agnostic
OSI layers - Answer-Physical, Data Link, Network, Transport, Session, Presentation,
Application
Physical layer - Answer-Transmission of bit stream; focus on signaling techniques;
does NOT include physical media
Data link layer - Answer-Manages frames for error-free data transfer point-to-point;
CRC integrity checking
Data link layer sub-layers - Answer-MAC; LLC
Network layer - Answer-enables internetworking; unique addressing for every node,
determines routes; unreliable for error detection and correction;
packets(reliable)/datagrams); routable (IP) and routing protocols
Transport layer - Answer-host-to-host integrity of transmission; detect damaged or
lost packets; messages/segments
Session layer - Answer-host-to-host interactive sessions; sockets (port + address)
Presentation layer - Answer-managing data presentation; encryption; character
conversion
Application layer - Answer-interface between user applications and network's
services via APIs; HTTP; SSH
What layer has "true adjacency" - Answer-only physical layer can communicate
directly with partner layer
Logical adjacency - Answer-1:1 correlation between layers between hosts
Encapsulation - Answer-higher level layers get wrapped by header and trailer of
lower level layers then gets sent to other host
Bandwidth - Answer-Theortical max
Throughput - Answer-Actual/realistic amount
,Analog bandwidth - Answer-Fmax-Fmin
What is the bandwidth of a digital signal - Answer-Infinite
Serial - Answer-one bit at a time; long distances
parallel - Answer-multiple bits at a time; short distances; EMI and degradation
Synchronous - Answer-time based with no gap between data items; timing
maintained regardless of presence of data
Isochronous - Answer-times based but has fixed gap between data items
Asynchronous - Answer-Signal based (start/stop bits); sync must be re-established
every communication cycle
what is an example of Serial & synchronous - Answer-USB, Firewire
what is an example of Serial & Asynchronous - Answer-"terminal" applications,
keyboard, console, mice
what is an example of Parallel & Synchronous - Answer-PCIe
what is an example of Parallel & Asynchronous - Answer-Not much
Simplex - Answer-Unidirectional and cannot change direction
Half-duplex - Answer-Unidirectional but can change directions (walkie-talkies)
Full-duplex - Answer-Bidirection concurrent communication
Auto-negotiation - Answer-auto set link speed and duplex mode
Modulation - Answer-Converting digital bits to analog signal
Demodulation - Answer-Converting analong signal to digital bits
Modem - Answer-Does both modulation and demodulation
Amplitude modulation - Answer-Data signal changes the amplitude of the carrier
wave, leaving frequency the same
Frequency modulation - Answer-Data signal changes the frequency of the carrier
wave, leaving the amplitude and phasing alone; FSK
Phase modulation - Answer-Data signal changes the phasing of the carrier wave,
leaving the frequency and amplitude the same; PSK
Shift keying - Answer-Digital data signal changes the amplitude of the carrier wave
, Quadratude Amplitude Modulation - Answer-Clock-like modulation; amplitude and
phasing indicated data
Multiplexing - Answer-Allow multiple signals to move over a single medium
Demultiplexing - Answer-Taking a muxed signal and splitting back into original
signals
Frequency Division Multiplexing - Answer-data streams are assigned that a specific
sub-frequency of the channel; guard band to minimize interference
Time division multiplexing - Answer-data stream is assigned to a timeslot on the
channel and can only send during that timeslot
Code division multiplexing - Answer-data stream is assigned to a unique orthogonal
code for use in the entire channel; overlapping data streams are ignored
802.2 - Answer-logical link control
802.3 - Answer-ethernet
802.11 - Answer-wireless/WLAN
802.15 - Answer-PAN/bluetooth
802.1Q - Answer-VLAN trunking/tagging
Copper media - Answer-STP, UTP, Cat5e/6, TIA568A/B
Straight-through cable - Answer-Connecting dissimilar devices
Crossover cable - Answer-Connecting similar devices
Rollover cable - Answer-Connect to Cisco serial port
Coaxial cable - Answer-Insulated single copper wire that can run longer distance
Hybrid Fiber-Coax (HFC) - Answer-Fiber and coax to allow two way communication
over coax cable
Shielded twisted pair - Answer-Each twisted pair is shielded, as well as the entire
bundle of wires
Fiber media - Answer-Requires two fibers for full duplex operation
Single mode - Answer-Can only carry single ray of light, longer distance
Multimode - Answer-Can carry mutiple rays of light, shorted distance
Open System Interconnection (OSI) - Answer-7 layers for open interconnection
between any two systems regardless of vendor
OSI rules - Answer-layers can only communicate with adjacent layers
OSI benefits - Answer-break network communication into more manageable parts
and vendor agnostic
OSI layers - Answer-Physical, Data Link, Network, Transport, Session, Presentation,
Application
Physical layer - Answer-Transmission of bit stream; focus on signaling techniques;
does NOT include physical media
Data link layer - Answer-Manages frames for error-free data transfer point-to-point;
CRC integrity checking
Data link layer sub-layers - Answer-MAC; LLC
Network layer - Answer-enables internetworking; unique addressing for every node,
determines routes; unreliable for error detection and correction;
packets(reliable)/datagrams); routable (IP) and routing protocols
Transport layer - Answer-host-to-host integrity of transmission; detect damaged or
lost packets; messages/segments
Session layer - Answer-host-to-host interactive sessions; sockets (port + address)
Presentation layer - Answer-managing data presentation; encryption; character
conversion
Application layer - Answer-interface between user applications and network's
services via APIs; HTTP; SSH
What layer has "true adjacency" - Answer-only physical layer can communicate
directly with partner layer
Logical adjacency - Answer-1:1 correlation between layers between hosts
Encapsulation - Answer-higher level layers get wrapped by header and trailer of
lower level layers then gets sent to other host
Bandwidth - Answer-Theortical max
Throughput - Answer-Actual/realistic amount
,Analog bandwidth - Answer-Fmax-Fmin
What is the bandwidth of a digital signal - Answer-Infinite
Serial - Answer-one bit at a time; long distances
parallel - Answer-multiple bits at a time; short distances; EMI and degradation
Synchronous - Answer-time based with no gap between data items; timing
maintained regardless of presence of data
Isochronous - Answer-times based but has fixed gap between data items
Asynchronous - Answer-Signal based (start/stop bits); sync must be re-established
every communication cycle
what is an example of Serial & synchronous - Answer-USB, Firewire
what is an example of Serial & Asynchronous - Answer-"terminal" applications,
keyboard, console, mice
what is an example of Parallel & Synchronous - Answer-PCIe
what is an example of Parallel & Asynchronous - Answer-Not much
Simplex - Answer-Unidirectional and cannot change direction
Half-duplex - Answer-Unidirectional but can change directions (walkie-talkies)
Full-duplex - Answer-Bidirection concurrent communication
Auto-negotiation - Answer-auto set link speed and duplex mode
Modulation - Answer-Converting digital bits to analog signal
Demodulation - Answer-Converting analong signal to digital bits
Modem - Answer-Does both modulation and demodulation
Amplitude modulation - Answer-Data signal changes the amplitude of the carrier
wave, leaving frequency the same
Frequency modulation - Answer-Data signal changes the frequency of the carrier
wave, leaving the amplitude and phasing alone; FSK
Phase modulation - Answer-Data signal changes the phasing of the carrier wave,
leaving the frequency and amplitude the same; PSK
Shift keying - Answer-Digital data signal changes the amplitude of the carrier wave
, Quadratude Amplitude Modulation - Answer-Clock-like modulation; amplitude and
phasing indicated data
Multiplexing - Answer-Allow multiple signals to move over a single medium
Demultiplexing - Answer-Taking a muxed signal and splitting back into original
signals
Frequency Division Multiplexing - Answer-data streams are assigned that a specific
sub-frequency of the channel; guard band to minimize interference
Time division multiplexing - Answer-data stream is assigned to a timeslot on the
channel and can only send during that timeslot
Code division multiplexing - Answer-data stream is assigned to a unique orthogonal
code for use in the entire channel; overlapping data streams are ignored
802.2 - Answer-logical link control
802.3 - Answer-ethernet
802.11 - Answer-wireless/WLAN
802.15 - Answer-PAN/bluetooth
802.1Q - Answer-VLAN trunking/tagging
Copper media - Answer-STP, UTP, Cat5e/6, TIA568A/B
Straight-through cable - Answer-Connecting dissimilar devices
Crossover cable - Answer-Connecting similar devices
Rollover cable - Answer-Connect to Cisco serial port
Coaxial cable - Answer-Insulated single copper wire that can run longer distance
Hybrid Fiber-Coax (HFC) - Answer-Fiber and coax to allow two way communication
over coax cable
Shielded twisted pair - Answer-Each twisted pair is shielded, as well as the entire
bundle of wires
Fiber media - Answer-Requires two fibers for full duplex operation
Single mode - Answer-Can only carry single ray of light, longer distance
Multimode - Answer-Can carry mutiple rays of light, shorted distance
