Cisco 640-722 Online Practice Questions and Exam Preparation

Cisco 640-722 Online Questions & Answers

• Question 91:

  How many types of control frames are only used in PCF mode?

  B. 1
  C. 2
  D. 3
  E. 4
  F. 5
  D. 3

• Question 92:

  

  

  Old 2.4-GHz wireless laptops are unable to connect. What is the most likely cause of this problem?

  A. WLAN > General properties are incorrectly configured.
  B. WLAN > QoS properties are incorrectly configured.
  C. WLAN > Security properties are incorrectly configured.
  D. WLAN > Advanced properties are incorrectly configured.
  E. Wireless > AP > 802.11 b/g/n AP is incorrectly configured.
  F. Wireless > AP > 802.11 b/g/n > Network is incorrectly configured.
  F. Wireless > AP > 802.11 b/g/n > Network is incorrectly configured.

  ---

  ClientLink is not enabled and should be in a mixed client environment. Many networks still support a mix of 802.11a/g and 802.11n clients. Because 802.11a/g clients (legacy clients) operate at lower data rates, the older clients can reduce the capacity of the entire network. Cisco's ClientLink technology can help solve problems related to adoption of 802.11n in mixed-client networks by ensuring that 802.11a/g clients operate at the best possible rates, especially when they are near cell boundaries.

• Question 93:

  How many dBm is 40 mW?

  A. 10 dBm
  B. 16 dBm
  C. 20 dBm
  D. 22 dBm
  E. 40 dBm
  B. 16 dBm

  ---

  The dB measures the power of a signal as a function of its ratio to another standardized value. The abbreviation dB is often combined with other abbreviations in order to represent the values that are compared. Here are two examples:

  

  dBm - The dB value is compared to 1 mW.

  

  dBw - The dB value is compared to 1 W.

  You can calculate the power in dBs from this formula:

  Power (in dB) = 10 * log10 (Signal/Reference)

  This list defines the terms in the formula:

  

  log10 is logarithm base 10.

  

  Signal is the power of the signal (for example, 50 mW).

  

  Reference is the reference power (for example, 1 mW).

  Here is an example. If you want to calculate the power in dB of 50 mW, apply the formula in order to get:

  Power (in dB) = 10 * log10 (50/1) = 10 * log10 (50) = 10 * 1.7 = 17 dBm

  Because decibels are ratios that compare two power levels, you can use simple math in order to manipulate the ratios for the design and assembly of networks. For example, you can apply this basic rule in order to calculate logarithms of

  large numbers:

  log10 (A*B) = log10(A) + log10(B)

  If you use the formula above, you can calculate the power of 50 mW in dBs in this way:

  Power (in dB) = 10 * log10 (50) = 10 * log10 (5 * 10) = (10 * log10 (5)) + (10 * log10(10)) = 7 + 10 = 17 dBm

  Reference: http://www.cisco.com/c/en/us/support/docs/wireless-mobility/wireless-lan-wlan/23231-powervalues-23231.html

• Question 94:

  What is the maximum number of lightweight APs that can be supported from a single Cisco WCS Navigator management console with Cisco WCS and Cisco WLC running version 7.0 code?

  A. 10,000
  B. 20,000
  C. 25,000
  D. 30,000
  E. 60,000
  D. 30,000

  ---

  The Cisco WCS Navigator supports partitioning of the unified wireless network at the management level. It supports up to 20 Cisco WCS management platforms with manageability of up to 30,000 Cisco Aironet lightweight access points from a single management console. It runs on a server platform with an embedded database.

• Question 95:

  

  

  When a client associates to ExamSSlD, which network address will be assigned?

  A. The IP address assigned will be based on the AP network assignment of 10.10.10.0.
  B. The IP address assigned will be based on the AP network assignment of 172.16.23.0.
  C. The IP address will be assigned in a round-robin format based on the 172.16.12.0, 172.16.23.0, 192.168.14.0 address pools.
  D. The IP address will be assigned in a round-robin format based on the 172.16.12.0, 192.168.14.0, 192.168.25.0 pools.
  E. The IP address will be assigned in a round-robin format based on the 172.16.12.0, 172.16.23.0, 192.168.14.0, 192.168.25.0 pools.
  D. The IP address will be assigned in a round-robin format based on the 172.16.12.0, 192.168.14.0, 192.168.25.0 pools.

  ---

  The IP addresses will be assigned round robin to the three interface groups, which we can see are vlan20, vlan40, and vlan50. From the WLC-interfaces tab we see that the IP addresses assigned to these 3 interfaces are 172.16.12.10, 172.16.14.10, and 192.168.25.10, respectively.

• Question 96:

  You are on the phone working with a colleague that is console connected to a lightweight AP that has lost its configuration. Which three actions are necessary to allow the AP to connect to a controller? (Choose three.)

  A. Configure the AP IP address.
  B. Configure the controller name.
  C. Configure the controller IP address.
  D. Configure the AP hostname.
  E. Configure the AP IP default-gateway.
  F. Configure the AP username and password.
  A. Configure the AP IP address.
  C. Configure the controller IP address.
  E. Configure the AP IP default-gateway.

  ---

  In order to manually configure static information on a LAP using the AP CLI interface, you can use these EXEC mode CLI commands:

  AP#capwap ap ip address

  AP#capwap ap ip default-gateway

  AP#capwap ap controller ip address

  AP#capwap ap hostname

  (optional)

  Notice the first 3 are needed for the AP to connect to the controller; the last step is optional and not needed for basic connectivity to the controller.

  Reference: http://www.cisco.com/c/en/us/support/docs/wireless/aironet-1200-series/99763-reset-lwappconfig-lap.html

• Question 97:

  DRAG DROP Refer to the exhibit. Drag the MAC addresses on the left that will allow the wireless station Host A to send a frame through a controller based AP to the wired station Host B and drop them in the correct order on the right. Not all options are used.

  Select and Place:

  

  

• Question 98:

  Which key combination provides a detailed wireless connection status for an Apple MacBook running 10.6?

  A. Command + Click the SSID of the network
  B. Alt + Click the SSID of the network
  C. Command + the Airport icon
  D. Option + the Airport icon
  E. Ctrl + the Airport Icon
  F. Option + Click the SSID of the network
  D. Option + the Airport icon

  ---

  You can hold the Option Key while clicking the Airport icon in the menu bar. This will provide you with more information about your connection status such as: data rate, signal strength, channel, etc.

  

  Reference: http://www.swilliamsgroup.com/3-ways-to-display-your-ssid-on-your-macbook/

• Question 99:

  What does RF determine?

  A. cycle pattern size
  B. how often a wave occurs
  C. signal size
  D. quantity of energy injected in a signal
  B. how often a wave occurs

  ---

  RF communication works by creating electromagnetic waves at a source and being able to pick up those electromagnetic waves at a particular destination. These electromagnetic waves travel through the air at near the speed of light. The wavelength of an electromagnetic signal is inversely proportional to the frequency; the higher the frequency, the shorter the wavelength.

  Reference: http://www.digi.com/technology/rf-articles/rf-basic

• Question 100:

  What must be done for Cisco WLC and Cisco WCS to communicate?

  A. The IP address and subnet mask of the Cisco WLC must be configured in the Cisco WCS.
  B. The IP address and subnet mask of the Cisco WCS must be configured in the Cisco WLC.
  C. The identity certificate of the Cisco WLC must be added to the Cisco WCS.
  D. The Cisco WLC and Cisco WCS must exchange identity certificates.
  A. The IP address and subnet mask of the Cisco WLC must be configured in the Cisco WCS.

  ---

  In Cisco WCS, you need to add the ip address and subnet of the WLC. Autodiscovery is a feature that is used to search for a single controller by IP Address however this feature is restricted to Cisco WLAN Solution mobility group subnets defined by the operator.