Final exam prep

Question 1

7- Layer OSI Protocol

Answer 1

application
Presentation
Session
Transport
Network
Data Link
Physical

Question 2

5 layer internet stack

Answer 2

Application
Transport
Internet
Network Access
Physical

Question 3

What does the physical layer do

Answer 3

Responsible for network interfacing: Transmission, Rate, Signaling, and Encoding

Question 4

What does the Network Access Layer do

Answer 4

Controls Access to Transmission Medium

Question 5

What Are the Standard Digital Encodings

Answer 5

Non-Return to Zero - level
Non-Return to Zero - Inverted
Bipolar-AMI
Pseudoternary
Manchester
Diff Manchester
B8ZS
HDB3

Question 6

Analog Econdings - Amplitude

Answer 6

ASK ( Amplitude shift Keying)
QAM ( Quadriture Shift Keying)

Question 7

Analog Encodings - Frequency

Answer 7

BFSK (Binary Frequency Shift Keying)
MFSK (Multiple Frequency Shift Keying)

Question 8

Analog Encodings - Phase

Answer 8

BPSK ( Binary Phase shift Keying)
QPSK ( Quadriture phase shift keying)
MPSK ( Multiple Phase shift keying)

Question 9

Role of a Modem

Answer 9

Digital to analog converter

Question 10

Role of a Codec

Answer 10

Convert analog to Digital Signals

Question 11

4 types of Noise

Answer 11

Bandwidth thermal Noise
Intermodulation Noise
Crosstalk Noise
Impulse Noise

Question 12

Intermodulation Noise

Answer 12

Multiple frequencies on same cable

Question 13

Crosstalk Noise

Answer 13

Noise caused by nearby signals

Question 14

Impulse Noise

Answer 14

Noise created by lightning for example

Question 15

Connection Orientated data Service

Answer 15

Connection and Termination needed to transfer data

Question 16

Connectionless Orientated Data Service

Answer 16

Does not need to establish connection and terminate in order to transfer between devices.

Question 17

Frequency Division Multiplexing

Answer 17

Breaks Channels uip into equal frequency bands

Question 18

Time Division Multiplexing

Answer 18

Round Robin, allows each channel a time slot

Question 19

Even and Odd parity

Answer 19

Add parity bit to make the number of 1s even or odd

Question 20

Limitations of parity

Answer 20

Can only find an odd amount of errors

Question 21

Need for Flow Control

Answer 21

Allows the reciever to finsih processing without concern of overflow

Question 22

Common Flow Control Algorithms

Answer 22

Stop and Wait
Sliding Window

Question 23

Stop and Wait Algorithm

Answer 23

Source sends frame and waits for ACK before sending next

Question 24

Sliding Window

Answer 24

Reciever uses buffer of size W
Transmitter send W frames without ACK

Question 25

Error Control

Answer 25

Needed to recover lost or damaged Frames

Question 26

ARQ Methods

Answer 26

Stop and Wait If no ACK before timer runs out retransmit Go Back N ARQ Sliding window, go back N frame Retransmit all Selective Reject Only resend frame N

Question 27

Structure of Twisted Pair Cable

Answer 27

Copper cables sheathed and spiraled around eachother to reduce cross talk

Question 28

Common name of Twisted pair Jack

Answer 28

RJ45

Question 29

Structure of Coaxial Cable

Answer 29

Core conductor -> Dielectric->Sheild->Jacket

Question 30

Structure of Fiber optic cable

Answer 30

Core is bundle of fibers each coated in cladding that reflects light back into the fiber

Question 31

Contention

Answer 31

Any Computer can transmit data at any time, uses different methods to avoid collisions

Question 32

IEEE 802.3 CSMA (Carrier Sense multiple Access) Algorithm

Answer 32

Responsible for idle line monitoring Responsible for playing fair oon a shared medium

Question 33

IEEE 802.3 CD

Answer 33

Responsible for detecting and announcing collisions

Question 34

IPv4 Address Length

Answer 34

32 bits

Question 35

802.3 Mac Addtess Length

Answer 35

48 bits