BP12

1
What is the IEEE standard for WLANs?

802.5

803.3

802.10

802.11***



2
What is the primary function of Cisco Aironet Wireless LAN Adapters, also referred to as client adapters?

to connect a wireless device to the wired infrastructure providing a common DS

to provide communication between fixed, portable, and mobile devices

to transfer data packets through the wired infrastructure

to transfer data packets through the wireless infrastructure***



3
What are the four modulation formats and data rates specified for the High Rate PHY? (Select four.)

differential quadrature convolutional coding (DQCC) mode for 2 Mbps

differential binary phase shift keying (DBPSK) modulation for 1 Mbps***

packet binary convolutional coding (PBCC) mode for enhanced performance***

differential quadrature phase shift keying (DQPSK) modulation for 2 Mbps***

compensatory differential code keying (CDCK) modulation scheme for 5.5 Mbps and 11 Mbps

complementary code keying (CCK) modulation scheme for 5.5 Mbps and 11 Mbps***



4
Where does IR PHY operate?

indoor environments only***

indoor and outdoor environments

outdoor environments only

well-lit environments only



5
What are the three non-overlapping IEEE 802.11b High Rate operating channels used in North America?

1, 3, 11

1, 3, 13

1, 6, 11***

2, 6, 11

2, 7, 13



6
What is the frequency range of operation in the 802.11a standard for WLANs?

2.4 GHz

11 GHz

5 GHz***

5.5 GHz



7
What is the best way to get specific software drivers for Cisco wireless adapter cards?

Order them directly from a Cisco retailer.

Download them from the CCO site.***

Purchase them at any computer retail store.

They are already installed on portable devices.



8
In the 802 Reference Model, which connection services does the LLC provide for the upper layer protocol (ULP)? (Select three.)

acknowledged multicast

unacknowledged connectionless***

acknowledged broadcast

acknowledged connection-oriented***

acknowledged connectionless***



9
What is a major advantage of the 802.11g standard for WLANs?

It achieves data rates in the range of 5.5 Mbps to 11 Mbps in the 5 GHz frequency range.

It achieves data rates up to 54 Mbps in the 2.4 GHz frequency range.***

It achieves data rates up to 54 Mbps in the 5 GHz frequency range.

It is an archaic protocol that is rarely used.



10
Distributed Coordination Function, the fundamental access method of the IEEE 802.11 MAC, uses which type of media access?

carrier sense multiple access with collision avoidance***

carrier sense multiple access with collision detection

contention-free access

carrier sense multiple access with collision delay



11
Which layers of the OSI model are primarily supported by the 802.11 standard? (Select two.)

Layer 1***

Layer 2***

Layer 3

Layer 4

Layer 5

Layer 6



12
In addition to faster speeds, what is the benefit of the 802.11g WLAN standard?

It provides interoperability among and between all WLAN speeds working at the 2.4 GHz frequency eliminating the need for a complete equipment upgrade.***

It provides interoperability between 5.5 Mbps and 54 Mbps WLAN speeds at 5 GHz thus allowing for compatibility with legacy systems and new devices.

It uses the CCK waveform which offers much higher speeds, greater ranges, and better tolerance of multipath echoes which are common to internal building applications.

It uses a hybrid of OFDM for slow data rates and CCK for fast data rates allowing both waveforms to coexist on the same WLAN.



13
Which two protocols combined are functionally equivalent to Layer 2 of the OSI model? (Select two.)

802.1x

802.11 PHY

802.11 MAC***

802.2 LLC***

802.2 LSS



14
In the 802.11 standard, which mechanism provides security services for the WLAN?

Wired Equivalent Protocol

Wireless Ethernet Protocol

Wireless Ethernet Privacy

Wired Equivalent Privacy***



15
What is the benefit of using Complementary Code Keying (CCK)?

In the 802.11a standard, it is used to increase peak data rates from 1 Mbps to 2 Mbps.

In the 802.11b standard, it is used to increase peak data rates from 2 Mbps to 11 Mbps.***

In the 802.11b standard, it is used to increase peak data rates from 11 Mbps to 54 Mbps.

In the 802.11g standard, it is used to maintain peak data rates of 54 Mbps.





16
What is the primary service of the 802.11 standard?

to detect collisions between MAC Service Data Units (MSDUs) on the wireless medium

to deliver MAC Service Data Units (MSDUs) between peer LLC devices***

to ensure reliable delivery of MAC Service Data Units (MSDUs) with error correction

to provide secure delivery of MAC Service Data Units (MSDUs)



17
In addition to physically installing the client adapter card into the wireless station, what is needed for functionality of the card?

a universal client adapter software driver

an interoperability software patch

a client adapter driver with its corresponding AP driver

a client adapter software driver specific to the OS***



18
What is orthogonal frequency division multiplexing (OFDM) and how is it used in the 802.11a standard?

A technique that allows short bursts of data to be transmitted on a narrow frequency band and then change to another frequency to continue the data transmission

A technique that divides a communications channel into a number of equally-spaced frequency bands and reduces multipath interference***

A technique that allows two or more channels of information to be transmitted at the same time by allocating a different time interval for the transmission of each frequency channel and eliminating multipath interference

A technique that enables a signal to be transmitted across a frequency band that is much wider than the minimum bandwidth required by the information signal thus reducing multipath interference