Ch.2 Data transmission

Question 1

packet

Answer 1

a small unit of data

Question 2

packet header

Answer 2

a section of a packet of data that contains information about the contents of the packet and its destination

Question 3

internet protocol (IP) address

Answer 3

the unique address that is given to a device when it is connected to a network

Question 4

payload

Answer 4

the actual data that the user is sending to the receiver

Question 5

trailer

Answer 5

a section of a packet of data that contains information about any error checking methods that may be used

Question 6

packet switching

Answer 6

a method of transmitting data packets across a network
each data packet is able to take an individual pathway across the network

Question 7

network

Answer 7

computers and devices that are joined together using cables or wireless technology

Question 8

router

Answer 8

a network component that examines a data packet to obtain its destination address and then forward the packet to this address

Question 9

serial

Answer 9

a transmission method where data is sent one bit at a time down a single wire

Question 10

parallel

Answer 10

a transmission method where data is sent multiple bits at a time down multiple wires

Question 11

interference

Answer 11

disruption, such as eletromagnetism, to data when it is transmitted

Question 12

simplex

Answer 12

a transmission method where data is transmitted in a single direction only

Question 13

half-duplex

Answer 13

a transmission method where data is transmitted in both directions, but only one direction at a time

Question 14

full-duplex

Answer 14

a transmission method where data is transmitted in both directions at the same time

Question 15

parity check

Answer 15

a type of error detection method that adds an additional bit to each byte to create an odd or even sum

Question 16

checksum

Answer 16

a type of error detection method that performs a calculation on the data to create a checksum value
checksum values are compared after transmission to see if they match

Question 17

echo check

Answer 17

a type of error detection method that sends a copy of the transmitted data back to the sender to be compared with the original data sent

Question 18

automatic repeat request (ARQ)

Answer 18

a type of error detection method that uses acknowledgement and timeout to see if data has arrived correctly after transmission

Question 19

acknowledgement

Answer 19

a message that is sent from one device to another to indicate whether data is received correctlyt

Question 20

timeout

Answer 20

a period of time that is set and used to wait for an acknowledgement to be received

Question 21

check digit

Answer 21

a type of error detection method that is used for data entry
a calculation is performed on the data entered to create a value
check digit values are compared to see if the data entered is correct

Question 22

encryption

Answer 22

a method of securing data for storage or transmission that scrambles it and makes it meaningless

Question 23

plain text

Answer 23

the name given to data before encryption

Question 24

encryption key

Answer 24

a type of algorithm that is used to encrypt data

Question 25

cipher text

Answer 25

the name given to data after transmission

Question 26

symmetric

Answer 26

a type of encryption that uses the same key to encrypt and decrypt data

Question 27

asymmetric

Answer 27

a type of encryption that uses two different keys to encrypt and decrypt data