ESAT Forouzan - Chapter 14: Local Area Networks (Ethernet)

Question 1

What is the hexadecimal equivalent of the Ethernet address 01011010 00010001 01010101 00011000 10101010 00001111?
a. 5A-88-AA-18-55-F0
b. 5A-81-BA-81-AA-0F
c. 5A-18-5A-18-55-0F
d. 5A-11-55-18-AA-0F

Answer 1

d. 5A-11-55-18-AA-0F

Question 2

If an Ethernet destination address is 07-01-02-03-04-05, then this is a ______ address.
a. Unicast
b. Multicast
c. Broadcast
d. Any of the above

Answer 2

b. Multicast

Question 3

If an Ethernet destination address is 08-07-06-05-44-33, then this is a ______ address.
a. Unicast
b. Multicast
c. Broadcast
d. Any of the above

Answer 3

a. Unicast

Question 4

Which of the following could not be an Ethernet source address?
a. 8A-7B-6C-DE-10-00
b. EE-AA-C1-23-45-32
c. 46-56-21-1A-DE-F4
d. 8B-32-21-21-4D-34

Answer 4

d. 8B-32-21-21-4D-34

Question 5

Which of the following could not be an Ethernet unicast destination?
a. 43-7B-6C-DE-10-00
b. 44-AA-C1-23-45-32
c. 46-56-21-1A-DE-F4
d. 48-32-21-21-4D-34

Answer 5

a. 43-7B-6C-DE-10-00

Question 6

Which of the following could not be an Ethernet multicast destination?
a. B7-7B-6C-DE-10-00
b. 7B-AA-C1-23-45-32
c. 7C-56-21-1A-DE-F4
d. 83-32-21-21-4D-34

Answer 6

c. 7C-56-21-1A-DE-F4

Question 7

A 10-station Ethernet LAN uses a _______-port bridge if the effective average data rate for each station is 2 Mbps.
a. 1
b. 2
c. 5
d. 10

Answer 7

c. 5

Question 8

A _______-station Ethernet LAN uses a four-port bridge. Each station has an effective average data rate of 1.25 Mbps.
a. 32
b. 40
c. 80
d. 160

Answer 8

a. 32

Question 9

Forty stations are on an Ethernet LAN. A 10-port bridge segments the LAN. What is the effective average data rate of each station?
1.0 Mbps
2.0 Mbps
a. 2.5 Mbps
b. 5.0 Mbps

Answer 9

a. 2.5 Mbps

Question 10

An 80-station traditional Ethernet is divided into four collision domains. This means that a maximum of _______ stations contend for medium access at any one time.
a. 320
b. 80
c. 76
d. 20

Answer 10

d. 20

Question 11

What is the efficiency of 4B/5B block encoding?
a. 20 percent
b. 40 percent
c. 60 percent
d. 80 percent

Answer 11

d. 80 percent

Question 12

What is the efficiency of a frame in half-duplex Gigabit Ethernet carrying 46 bytes of data?
a. 97 percent
b. 70 percent
c. 56 percent
d. 12 percent

Answer 12

b. 70 percent

Question 13

Which of the following is a four-wire Gigabit Ethernet implementation?
a. 1000Base-SX
b. 1000Base-LX
c. 1000Base-CX
d. 1000Base-T

Answer 13

d. 1000Base-T

Question 14

What is the efficiency of 8B/10B encoding?
a. 20 percent
b. 40 percent
c. 60 percent
d. 80 percent

Answer 14

d. 80 percent