Exam CISCO 642-831 Demo

1.EIRP is a measurement typically calculated in _____.646-573

A: dBl
B: dBr
C: dBd
D: dBm
Correct Answers:  D642-551

2.Which antenna provides the most flexibility at the central location of a point-to-multipoint bridging application?1z0-101

A: isotropic antenna
B: 12 dBi omni-directional
C: 23 dBi grid dish antenna
D: 21 dBi parabolic dish antenna
Correct Answers:  B70-630  70-281  70-631

3.When doing a survey in a hospital application, which three should you consider? (Choose three.)050-692

A: pagers
B: fire doors
C: televisions
D: microwave ovens
E: radiology/x-ray areas
Correct Answers:  B, D, EHP0-764

4.What is the maximum Ethernet run from the Cisco Aironet 1400 Series Bridge to the switch or router?000-636

A: 10 km (maximum distance for single mode fiber)
B: 100 meters (maximum distance for Fast Ethernet)
C: 500 meters (Cisco Aironet 1400 Series uses a hybrid Ethernet/fiber interface.)
D: 200 meters (100 meters from Switch to Power Injector, then another 100 meters to Bridge Outdoor Unit (ODU)
Correct Answers:  D MB5-198  MB3-234

5.What does the 802.11g protection mechanism do? MB4-161  MB3-412

A: uses the CTS (clear to send) to manage the transmit power of all clients
B: reduces the data rate for 802.11g clients when 802.11b clients are in the same cell
C: reduces the transmit power of 802.11b clients when 802.11g clients are in the same cell
D: uses CTS (clear to send) to protect 802.11g clients from collisions with 802.11b clients
Correct Answers:  DMB6-291  MB3-006

6.Why are diversity antennas used indoors?MB2-421

A: They are smaller in size.
B: They are designed to handle multi-path.
C: They have lower transmit signal strength than standard antennas.
D: They have higher transmit signal strength than standard antennas.
Correct Answers:  BMCSE

7.Which specific antenna architecture is used to help eliminate RF null areas of coverage?

A: splitters
B: diversity
C: high gain omni
D: patch antennas
Correct Answers:  B70-631

8.What is the purpose of the WPA 4-way handshake?

A: authenticates users
B: negotiates broadcast keys
C: derives WPA unicast keys
D: negotiates the encryption cipher types
Correct Answers:  CHP0-053

9.Which statement is true about the Cisco Aironet 1400 Series Bridge?

A: It does not support wireless clients.
B: It supports wireless clients only on a root bridge per IEEE specification.
C: It supports wireless clients only on a non-root bridges with valid links to a root bridge.
D: It supports wireless clients on a root bridge when a wireless client MAC address is set to forward.
Correct Answers:  A1z0-043

10.Which statement about non-overlapping channels is true?HP0-239 HP0-762

A: Non-overlapping channels share the same frequencies to improve roaming.
B: Non-overlapping channels use different frequency bands to improve roaming.
C: Non-overlapping channels share the same frequencies but use different modulations to avoid interference.
D: Non-overlapping channels use the same frequency band but use non-shared frequencies to avoid interference.
Correct Answers:  D310-560 310-615

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