CWNP PW0-250 問題集

質問 1：
You are working on a VoWLAN design with your customer's wired networking team. How many distinct priority levels do you expect for the voice applications?
A. 1 priority level per client and AP pair, so the total number depends on the expected number of clients
B. 1 priority level, but 2 queues (one for uplink traffic, one for downlink traffic)
C. 1 priority level for voice RTP, 1 priority level for voice control and RTCP
D. 1 priority level for VoWLAN client traffic, 1 priority level for wired VoIP client traffic
正解：C

質問 2：
An associated STA detects a new BSS with the same SSID as the STA's current BSS. The new BSS uses a different IP subnet than the current BSS. If the STA is configured to use 802.1X/EAP preauthentication, what is likely to occur?
A. The STA will attempt to preauthenticate and succeed if the current AP has shared its cached PMK.
B. The STA will attempt to preauthenticate and succeed if IP Mobility is enabled on the AP or WLAN controller.
C. The STA will attempt to preauthenticate and succeed if DHCP is supported on the new subnet.
D. The STA will attempt to preauthenticate, but fail because the new BSS uses a different data-link broadcast domain.
E. The STA will not attempt to preauthenticate because the new BSS uses a different IP subnet.
正解：D

質問 3：
You are tasked with designing the WLAN to accommodate certain high density areas on your university campus where users are highly transient (frequently come and go). With a limited DHCP pool size (subnet mask = 255.255.252.0) for this WLAN subnet, you want to ensure that your DHCP addresses are used efficiently and are not exhausted, which would prevent new client associations. The DHCP server is a Windows Server 2008 machine. Your design task is to determine the best configuration to allow as many users as possible while avoiding WLAN service interruptions and also to use the available addresses as efficiently as possible.
What setting would be most effective at achieving this design task?
A. Enable mandatory admission control
B. Set the maximum client limit per radio to 64
C. Enable WLAN Controller DHCP relay
D. Set the AES rekey interval to 5 minutes
E. Set the 802.1X re-authentication timer to 10 minutes
F. Set the DHCP lease for this pool to 20 minutes
G. Set the inactive wireless client timeout (client age-out) to 5 minutes
H. Set the RTS threshold to 2346 bytes
正解：F

質問 4：
At a university, the WLAN has been successfully deployed for ubiquitous access for faculty, students, and guests. Many student computer labs are available throughout the campus with wired network connectivity, but there are also a few smaller lab areas and workstations where Ethernet cabling is not available. For student wireless use, the students must authenticate against RADIUS/Active Directory using PEAP. Also, the network administrators at this university would like administrative access to these workstations when they are not in use by students so that the administrators can manage group policies, update OS patches, and perform other routine software maintenance.
What deployment options are available and recommended for both student use and remote administration of these workstations? (Choose 2)
A. The WLAN infrastructure vendor is responsible for providing proprietary client connectivity options to facilitate device connectivity without user interaction.
B. Due to the architecture of 802.1X port-based access control, it is not possible for a wireless-only computer to access network services required by network administrators in this scenario.
C. Machine authentication accounts should be enabled to provide persistent machine network connectivity when student users are not associated.
D. These stations should be deployed with dual WLAN adapters. One adapter would be used for consistent network connectivity for administrative purposes and the second adapter should be used for student access.
E. These workstations should be Ethernet-connected to a wireless client bridge, which will maintain network connectivity independent of student connectivity status.
正解：C,E

質問 5：
You captured the wireless frame shown in the exhibit during a post-deployment verification site survey.

What can you tell the customer about this network?
A. This is a video stream packet, and there is a QoS marking issue on the wired side, because the DSCP value should not be set to 0.
B. This is a voice control packet, and the configuration looks normal, as voice control may or may not have a DSCP tag.
C. This is a video stream packet, and the configuration looks normal, as DSCP is always set to 0 when 802.11e QoS is specified at Layer 2.
D. This is a voice RTP packet, and its marking was downgraded from Voice to Video which is a sign of congestion issues.
正解：B

質問 6：
Given: The 802.11n APs you have selected for your public access deployment support many of the PHY and MAC enhancements offered by the 802.11n standard. The AP is single-band (2.4 GHz) and only allows 20 MHz channels. The WLAN radio in the AP is a 3x3 802.11n chip that supports two spatial streams.
What is the maximum MCS rate that could be supported by this AP?
A. 54 Mbps
B. 150 Mbps
C. 144 Mbps
D. 65 Mbps
E. 108 Mbps
F. 300 Mbps
正解：C