Q1. When reviewing a design for a voice over wireless deployment, what per-call bandwidth cost should be factored in when determining maximum calls per cell using SIP and G.711u as the codec?
A. 64 bytes
B. 8 bytes
C. 80 bytes
D. 10 bytes
Answer: C
Q2. An engineer is deploying centralized wireless solution with a 5508 controller. What is the most AP licenses that can be supported?
A. 100
B. 250
C. 1000
D. 500
Answer: D
Explanation:
You can order Cisco 5500 Series Controllers with support for 12, 25, 50, 100, 250 or 500 APs as the controller's base capacity. You can add additional AP capacity through capacity adder licenses available at 25, 50, 100 and 250 AP capacities. You can add the capacity adder licenses to any base license in any combination to arrive at the maximum capacity of 500 APs.
Reference: http://www.cisco.com/c/en/us/support/docs/wireless/5500-series-wireless-controllers/112926-5508wlc-license.html
Q3. Refer to the exhibit.
While testing the post-deployment WLAN network, you discover that an AP has been placed in a difficult area.
The AP cannot be moved easily because of various requirements. The client performance of various Apple and Microsoft operating system-based products does not meet expectations. Which two options can help mitigate the performance issue? (Choose two.)
A. Add additional APs.
B. Increase the AP power level to maximum.
C. Rotate the AP 90 degrees to change antenna polarity.
D. Replace the AP with an AP and external antenna.
E. Change the AP location to one that is less RF hostile.
Answer: A,D
Q4. A customer has dual-band devices that they want to use 40 MHz channels. If the customer is using Cisco 3600 Series access points with a 5508 controller. Which setting assists with this change?
A. Enable band select globally.
B. Enable aggressive load balancing.
C. Disable lower data rates on 802 .11G GHz radios.
D. Disable overlapping 802.11G channels.
Answer: A
Q5. An engineer is configuring an autonomous AP for RADIUS authentication. What three pieces of information must be known to configure the AP? (Choose three.)
A. BVI IP address
B. group name
C. RADIUS IP address
D. PAC encryption key
E. username and password
F. shared secret
Answer: A,C,F
Q6. An engineer plugs in a Cisco Aironet 2700 Series Access Point and it is running in low power. Which three power requirements should be verified? (Choose three.)
A. 802.3ac compliant
B. 802.3at compliant
C. AP requires 43 VDC to function in full power.
D. AIR-PWRINJ3 power injector should be used.
E. AP requires 57 VDC to function in full power.
F. AIR-PWRINJ4 power injector should be used.
Answer: B,E,F
Explanation:
The access point should be powered by any 802.3at compliant device.
The recommended external power supply for the access point is the Cisco AIR-PWR-B power supply. The access point can also be powered by the following optional external power sources:
– Access point power injector (AIR-PWRINJ4)
– Any 802.3af compliant power injector is supported, but in this case the access point will dynamically shift from 3x4 to 3x3.
Reference: http://www.cisco.com/c/en/us/td/docs/wireless/access_point/2700/quick/guide/ap2700getst art.html
Q7. Which three options are benefits of U-APSD? (Choose three.)
A. optimized power-save mode periods
B. increased call capacity
C. bandwidth reservation
D. synchronization of the transmission and reception of voice frames
E. efficient roaming
F. priority bandwidth and polling
Answer: A,B,D
Explanation:
Unscheduled automatic power-save delivery (U-APSD) is a feature that has two key benefits:
The primary benefit of U-APSD is that it allows the voice client to synchronize the transmission and reception of voice frames with the AP, thereby allowing the client to go into power-save mode between the transmission/reception of each voice frame tuple. The WLAN client frame transmission in the access categories supporting U-APSD triggers the AP to send any data frames queued for that WLAN client in that AC. A U-APSD client remains listening to the AP until it receives a frame from the AP with an end-of-service period (EOSP) bit set. This tells the client that it can now go back into its power-save mode. This triggering mechanism is considered a more efficient use of client power than the regular listening for beacons method, at a period controlled by the delivery traffic indication map (DTIM) interval, because the latency and jitter requirements of voice are such that a WVoIP client would either not be in power-save mode during a call, resulting in reduced talk times, or would use a short DTIM interval, resulting in reduced standby times. The use of U-APSD allows the use of long DTIM intervals to maximize standby time without sacrificing call quality. The U-APSD feature can be applied individually across access categories, allowing U-APSD can be applied to the voice ACs in the AP, but the other ACs still use the standard power save feature.
The secondary benefit of this feature is increased call capacity. The coupling of transmission buffered data frames from the AP with the triggering data frame from the WLAN client allows the frames from the AP to be sent without the accompanying interframe spacing and random backoff, thereby reducing the contention experience by call.
Reference:
http://www.cisco.com/c/en/us/td/docs/solutions/Enterprise/Mobility/vowlan/41dg/vowlan41dg-book/vowlan_ch2.html#wp1045982
Q8. Which two best practices should be considered when a customer wants to purchase and implement Voice over Wireless for Cisco 7925 IP Phones? (Choose two.)
A. Enable lower data rates for 2.4-GHz data WLAN and higher data rates for phones.
B. Use a separate Cisco Wireless Lan Controller.
C. Enable 802.1x and Cisco Centralized Key Management for phone authentication.
D. Use dedicated Access Points only for Voice over Wireless.
E. Set data for 2.4 GHz and voice for 5 GHz using separate SSIDs.
Answer: C,E
Q9. The AP has been configured property for a VoWLAN survey The RF environment contains a noise of -87 to -90 dBm. What is the target value for the cell edge reading?
A. -62 dBm
B. -67 dBm
C. -60 dBm
D. -70 dBm
Answer: B
Q10. While performing a Layer 1 passive wireless site survey of a location an engineer detects several instances of low power frequency hopping interference, but cannot physically locate the interfering device or devices. Why is the engineer unable to locate the offending device or devices?
A. The sources are nearby narrow-beam radar and are sweeping through the facility.
B. The sources are PAN and are mobile.
C. The sources are above the ceiling file and transmit intermittently.
D. The sources are actually high-powered devices and transmit from off the site.
Answer: B