Chapter 9

Question 1

This layer receives the MSDU and reframes it with an 802.11 frame header to create an MPDU.

Answer 1

Data Link Layer

Question 2

What are some of the advantages of using WMM-PS power management over legacy power management methods?

Answer 2

A) Applications control doze and trigger frames
B) The client does not have to wait for a beacon
C) Downlink traffic is sent in a frame burst
D) Data frames are used as trigger frames. PS-Poll frames are not used.
E) All of the above

Question 3

The data unit which resides on Layer 2 is called?

Answer 3

Frame

Question 4

This is the smallest unit of data in computer networking and is composed of either 0 or a 1.

Answer 4

Bit

Question 5

The MAC sublayer resides at which layer of the OSI model?

Answer 5

Layer 2

Question 6

The process a client goes through to join a BSS includes three states. These three states are different combinations of which two functions? (Choose Two)

Answer 6

A) Authentication

B) Association

Question 7

The 802.11 Shared Key Authentication method is used for which of the following security implementations in 802.11 networking?

Answer 7

WEP

Question 8

This process of breaking frames into smaller transmission units can sometimes improve performance of a wireless network which is experiencing high data corruption. However, using this can impede performance on a properly working wireless network.

Answer 8

Fragmentation

Question 9

The PMD sublayer resides at which layer of the OSI model?

Answer 9

Layer 1

Question 10

If a station is in Power Save Mode, how does it know that it has buffered unicast frames waiting for it?

Answer 10

By examining the TIM Field

Question 11

The Beacon frame is which type of frame?

Answer 11

Management Frame

Question 12

What is the name of the sub-layer that is responsible for modulating data onto the wireless media and creating the RF signal?

Answer 12

PMD

Question 13

After a station sees its AID in the TIM, what typically is the next frame that the station transmits?

Answer 13

PS-Poll

Question 14

If a client station is always awake and listening to the wireless medium with no periods of dozing which power save mode is the station using? This mode is sometimes referred to as Continuous Aware Mode.

Answer 14

Active Mode

Question 15

The process a client goes through to join a BSS includes three states. Which of the following happens first?

Answer 15

Authentication

Question 16

This sublayer takes a PSDU and adds an 802.11 preamble and PHY encoding to it to create a PPDU.

Answer 16

PLCP

Question 17

This is a frame typically sent by access points in an 802.11b/g mixed mode environment to allow 802.11b stations to set their NAV value. This frame is strictly used as a protection mechanism and is not solicited by an RTS frame.

Answer 17

CTS-to-Self

Question 18

When a client station roams from one BSS to another within an ESS, which type of management frame is sent to the new AP the client wishes to associate with?

Answer 18

Reassociation Request

Question 19

When 802.11g stations co-exist in a BSS with 802.11b stations, the 802.11g stations must use which of the following to ensure that the 802.11b stations can properly participate in the CSMA/CA process?

Answer 19

Protected Mode

Question 20

Why do 802.11g devices communicate at a slower throughput when in a mixed mode environment with 802.11b devices?

Answer 20

Because of the additional overhead and traffic created by RTS/CTS and CTS-to-Self frames

Question 21

The PLCP sublayer resides at which layer of the OSI model?

Answer 21

Layer 1

Question 22

What is the most likely problem if a client station is unauthenticated and associated?

Answer 22

A client station cannot be unauthenticated and associated

Question 23

The unit of data being manipulated is a PSDU. It is being converted into a PPDU. In which Layer of the OSI model is the data unit currently?

Answer 23

Physical Layer

Question 24

If a station is in Power Save Mode, how does it know that broadcast frames are pending transmission from the access point?

Answer 24

DTIM Interval

Question 25

ACK, RTS, and CTS are which type of frame?

Answer 25

Control Frames