{"id":18072,"date":"2026-09-22T05:12:25","date_gmt":"2026-09-22T05:12:25","guid":{"rendered":"https:\/\/www.examlabs.com\/certification\/?p=18072"},"modified":"2026-09-22T05:13:56","modified_gmt":"2026-09-22T05:13:56","slug":"cwnp-cwna-109-practice-test-questions-and-exam-dumps-part20-q381-400","status":"publish","type":"post","link":"https:\/\/www.examlabs.com\/certification\/cwnp-cwna-109-practice-test-questions-and-exam-dumps-part20-q381-400\/","title":{"rendered":"CWNP CWNA-109 Practice Test Questions and Exam Dumps Part20 Q381-400"},"content":{"rendered":"

View Full <\/b>CWNP CWNA-109 Exam Dumps<\/b><\/a> and Practice Test Dumps<\/b><\/h2>\n

 <\/p>\n

Question 381.<\/b><\/p>\n

Which 802.11 mechanism allows a station to determine whether the wireless medium is currently busy by directly sensing RF activity?<\/b><\/p>\n

    \n
  1. <\/b> Physical carrier sensing<\/span>
    \n<\/span>2.<\/b> Virtual carrier sensing<\/span>
    \n<\/span>3.<\/b> DHCP discovery<\/span>
    \n<\/span>4.<\/b> ARP inspection<\/span><\/li>\n<\/ol>\n

    Correct Answer: 1. Physical carrier sensing<\/b><\/p>\n

    Explanation:<\/b><\/p>\n

    Physical carrier sensing allows a Wi-Fi station to monitor the RF medium and determine whether another transmission is already in progress. It is one part of the carrier-sense process used by CSMA\/CA. Virtual carrier sensing uses duration information and the NAV rather than relying only on directly detected RF activity. DHCP and ARP operate at higher networking layers and do not determine whether the wireless channel is busy. Physical and virtual carrier sensing work together to help stations avoid transmitting over existing exchanges, which reduces collisions and improves shared-medium coordination.<\/span><\/p>\n

    Question 382.<\/b><\/p>\n

    Which WLAN mechanism uses the Network Allocation Vector to determine whether the channel is logically reserved?<\/b><\/p>\n

      \n
    1. <\/b> Physical carrier sensing<\/span>
      \n<\/span>2.<\/b> Virtual carrier sensing<\/span>
      \n<\/span>3.<\/b> Active scanning<\/span>
      \n<\/span>4.<\/b> Rate adaptation<\/span><\/li>\n<\/ol>\n

      Correct Answer: 2. Virtual carrier sensing<\/b><\/p>\n

      Explanation:<\/b><\/p>\n

      Virtual carrier sensing uses the Network Allocation Vector, or NAV, to track how long the medium should be treated as reserved based on duration information contained in received 802.11 frames. This allows a station to defer transmission even when it cannot directly hear every frame in an exchange. Physical carrier sensing relies on detected RF activity, while active scanning and rate adaptation serve different purposes. The NAV is particularly useful during exchanges such as RTS\/CTS, where surrounding stations can learn that the medium has been reserved for an upcoming transmission sequence.<\/span><\/p>\n

      Question 383.<\/b><\/p>\n

      Which problem is most likely when two clients can both communicate with an AP but cannot hear each other’s transmissions?<\/b><\/p>\n

        \n
      1. <\/b> Adjacent-channel interference<\/span>
        \n<\/span>2.<\/b> Polarization mismatch<\/span>
        \n<\/span>3.<\/b> Hidden-node condition<\/span>
        \n<\/span>4.<\/b> DHCP exhaustion<\/span><\/li>\n<\/ol>\n

        Correct Answer: 3. Hidden-node condition<\/b><\/p>\n

        Explanation:<\/b><\/p>\n

        A hidden-node condition occurs when two stations cannot detect one another but can both communicate with the same receiver, usually an AP. Each client may believe the channel is idle while the other is transmitting, causing overlapping frames at the AP and increasing retries. RTS\/CTS can sometimes reduce this problem by allowing the AP’s CTS frame to inform both clients that the medium is reserved. Adjacent-channel interference, polarization mismatch, and DHCP exhaustion are different issues and do not describe this specific medium-access problem.<\/span><\/p>\n

        Question 384.<\/b><\/p>\n

        Which feature can be used to reduce collisions caused by hidden nodes by reserving the medium before data transmission?<\/b><\/p>\n

          \n
        1. <\/b> WMM<\/span>
          \n<\/span>2.<\/b> OFDMA<\/span>
          \n<\/span>3.<\/b> Protected Management Frames<\/span>
          \n<\/span>4.<\/b> RTS\/CTS**<\/span><\/li>\n<\/ol>\n

          Correct Answer: 4. RTS\/CTS<\/b><\/p>\n

          Explanation:<\/b><\/p>\n

          RTS\/CTS provides a short reservation exchange before data transmission. A station sends Request to Send, and the receiver responds with Clear to Send. Stations that hear either part of the exchange can update their NAV and defer transmission for the indicated duration. This can reduce collisions in hidden-node environments, although it adds overhead and should not be enabled unnecessarily. WMM provides QoS, OFDMA improves multi-user efficiency, and Protected Management Frames address selected management-frame security rather than hidden-node contention.<\/span><\/p>\n

          Question 385.<\/b><\/p>\n

          Which statement best describes why Wi-Fi uses CSMA\/CA instead of classic CSMA\/CD?<\/b><\/p>\n

            \n
          1. <\/b> A wireless station generally cannot reliably detect a collision while transmitting<\/span>
            \n<\/span>2.<\/b> Wi-Fi does not use shared spectrum<\/span>
            \n<\/span>3.<\/b> Wi-Fi devices never retransmit frames<\/span>
            \n<\/span>4.<\/b> CSMA\/CD requires encryption<\/span><\/li>\n<\/ol>\n

            Correct Answer: 1. A wireless station generally cannot reliably detect a collision while transmitting<\/b><\/p>\n

            Explanation:<\/b><\/p>\n

            Wireless devices typically cannot transmit and simultaneously listen with enough sensitivity to detect collisions the way classic shared Ethernet did with CSMA\/CD. The station’s own transmit signal would overwhelm its receiver. Wi-Fi therefore uses collision avoidance techniques, including carrier sensing, random backoff, acknowledgments, and optional RTS\/CTS. If an expected ACK is not received, the sender can infer that the transmission may have failed and retry. CSMA\/CA is fundamental to how Wi-Fi devices share the half-duplex RF medium.<\/span><\/p>\n

            Question 386.<\/b><\/p>\n

            Which event normally causes a Wi-Fi transmitter to retry a unicast frame?<\/b><\/p>\n

              \n
            1. <\/b> The SSID is visible<\/span>
              \n<\/span>2.<\/b> The expected ACK is not received<\/span>
              \n<\/span>3.<\/b> The client has a DHCP address<\/span>
              \n<\/span>4.<\/b> The AP sends a Beacon<\/span><\/li>\n<\/ol>\n

              Correct Answer: 2. The expected ACK is not received<\/b><\/p>\n

              Explanation:<\/b><\/p>\n

              Many unicast Wi-Fi transmissions are expected to receive an acknowledgment. If the sender does not receive the expected ACK within the appropriate timing window, it may retransmit the original frame. Missing ACKs can result from interference, collisions, weak signal quality, hidden nodes, or receiver problems. DHCP addressing and Beacon transmission are unrelated to the retry decision. High retry rates consume valuable airtime because both the failed frame and its retransmission occupy the channel, making retries an important WLAN troubleshooting metric.<\/span><\/p>\n

              Question 387.<\/b><\/p>\n

              Which metric is most useful for identifying whether repeated transmission failures are consuming excessive WLAN airtime?<\/b><\/p>\n

                \n
              1. <\/b> SSID count<\/span>
                \n<\/span>2.<\/b> Beacon interval only<\/span>
                \n<\/span>3.<\/b> Retry rate<\/span>
                \n<\/span>4.<\/b> DHCP lease length<\/span><\/li>\n<\/ol>\n

                Correct Answer: 3. Retry rate<\/b><\/p>\n

                Explanation:<\/b><\/p>\n

                Retry rate indicates how often frames must be retransmitted because the original transmission was not successfully acknowledged. Elevated retries can consume substantial airtime and reduce application throughput even when RSSI appears acceptable. Common causes include interference, hidden nodes, contention, weak SNR, or poor client behavior. SSID count and beacon interval may affect overhead but do not directly measure failed data transmissions. Retry rate should be interpreted alongside channel utilization, RSSI, SNR, client density, and spectrum information to identify the underlying cause.<\/span><\/p>\n

                Question 388.<\/b><\/p>\n

                Which effect is most likely when a WLAN carries a large amount of traffic at very low PHY rates?<\/b><\/p>\n

                  \n
                1. <\/b> Airtime consumption decreases<\/span>
                  \n<\/span>2.<\/b> Co-channel contention disappears<\/span>
                  \n<\/span>3.<\/b> Channel utilization becomes irrelevant<\/span>
                  \n<\/span>4.<\/b> More airtime is required for the same payload**<\/span><\/li>\n<\/ol>\n

                  Correct Answer: 4. More airtime is required for the same payload<\/b><\/p>\n

                  Explanation:<\/b><\/p>\n

                  Low PHY rates require more time to transmit the same amount of application data. Because Wi-Fi is a shared medium, that additional transmission time reduces the amount of airtime available to other stations using the channel. This is why one slow client can have a disproportionate effect on aggregate capacity. Lower rates do not eliminate contention or make channel utilization irrelevant. WLAN design should therefore consider cell size, minimum supported rates, signal quality, and client capabilities to reduce excessive low-rate airtime consumption where appropriate.<\/span><\/p>\n

                  Question 389.<\/b><\/p>\n

                  Which WLAN configuration can increase management overhead when used excessively?<\/b><\/p>\n

                    \n
                  1. <\/b> Advertising many SSIDs<\/span>
                    \n<\/span>2.<\/b> Reducing unnecessary SSIDs<\/span>
                    \n<\/span>3.<\/b> Using appropriate channel reuse<\/span>
                    \n<\/span>4.<\/b> Balancing AP transmit power<\/span><\/li>\n<\/ol>\n

                    Correct Answer: 1. Advertising many SSIDs<\/b><\/p>\n

                    Explanation:<\/b><\/p>\n

                    Each advertised SSID generally results in additional Beacon traffic and can increase Probe Response overhead. When many SSIDs are configured, management traffic consumes a larger share of the available airtime, particularly if management frames are sent at low basic rates. Reducing unnecessary SSIDs can improve efficiency, while proper channel reuse and transmit-power design address different performance concerns. Enterprises should use only the SSIDs required for business needs and consider role-based or policy-based segmentation to avoid creating excessive wireless overhead.<\/span><\/p>\n

                    Question 390.<\/b><\/p>\n

                    Which WLAN design practice is most appropriate when the same building contains both high-density conference rooms and lightly used office areas?<\/b><\/p>\n

                      \n
                    1. <\/b> Use identical RF settings everywhere regardless of usage<\/span>
                      \n<\/span>2.<\/b> Design capacity and RF parameters according to the requirements of each area<\/span>
                      \n<\/span>3.<\/b> Use maximum transmit power on every AP<\/span>
                      \n<\/span>4.<\/b> Configure the widest possible channel in every location<\/span><\/li>\n<\/ol>\n

                      Correct Answer: 2. Design capacity and RF parameters according to the requirements of each area<\/b><\/p>\n

                      Explanation:<\/b><\/p>\n

                      Different areas can have very different WLAN requirements. A conference room may need high capacity and aggressive channel reuse because hundreds of clients can be active simultaneously, while a lightly used office area may require fewer APs. One universal power or channel-width setting may therefore be inefficient. WLAN design should account for expected client density, applications, mobility, coverage, capacity, security, and physical environment in each space. The goal is to satisfy requirements with efficient use of spectrum rather than applying maximum settings uniformly.<\/span><\/p>\n

                      Question 391.<\/b><\/p>\n

                      Which factor should be considered first when determining whether 20 MHz or a wider channel width is appropriate in a dense deployment?<\/b><\/p>\n

                        \n
                      1. <\/b> Available spectrum and channel reuse requirements<\/span>
                        \n<\/span>2.<\/b> AP chassis color<\/span>
                        \n<\/span>3.<\/b> DNS domain name<\/span>
                        \n<\/span>4.<\/b> User password length<\/span><\/li>\n<\/ol>\n

                        Correct Answer: 1. Available spectrum and channel reuse requirements<\/b><\/p>\n

                        Explanation:<\/b><\/p>\n

                        Channel width should be selected based on available spectrum, AP density, client density, channel reuse, and application requirements. Wider channels can increase peak PHY rate but consume more spectrum and reduce the number of independent channels available for nearby cells. In dense environments, 20 MHz channels often provide better aggregate capacity because they support greater reuse. Cosmetic hardware details, DNS names, and password length are unrelated to RF channel planning. The correct width should be chosen for overall network efficiency rather than maximum advertised speed.<\/span><\/p>\n

                        Question 392.<\/b><\/p>\n

                        Which feature is specifically intended to move a Wi-Fi device away from a channel when protected radar activity is detected?<\/b><\/p>\n

                          \n
                        1. <\/b> WMM<\/span>
                          \n<\/span>2.<\/b> DFS<\/span>
                          \n<\/span>3.<\/b> TWT<\/span>
                          \n<\/span>4.<\/b> PMF<\/span><\/li>\n<\/ol>\n

                          Correct Answer: 2. DFS<\/b><\/p>\n

                          Explanation:<\/b><\/p>\n

                          Dynamic Frequency Selection, or DFS, is used on certain 5 GHz channels to protect radar systems that share the spectrum. Wi-Fi equipment must monitor for radar and follow regulatory requirements when radar is detected, which can include stopping operation on the affected channel and moving elsewhere. WMM handles QoS, TWT supports scheduled power saving, and PMF protects selected management frames. DFS can make additional 5 GHz spectrum available for WLAN use, but designers must consider radar events and client support when using these channels.<\/span><\/p>\n

                          Question 393.<\/b><\/p>\n

                          Which Wi-Fi 6 feature can improve efficiency when many clients send or receive relatively small amounts of data?<\/b><\/p>\n

                            \n
                          1. <\/b> WEP<\/span>
                            \n<\/span>2.<\/b> Passive scanning<\/span>
                            \n<\/span>3.<\/b> OFDMA<\/span>
                            \n<\/span>4.<\/b> Static channel assignment only<\/span><\/li>\n<\/ol>\n

                            Correct Answer: 3. OFDMA<\/b><\/p>\n

                            Explanation:<\/b><\/p>\n

                            OFDMA divides a channel into smaller resource units that can be assigned to multiple clients during the same transmission opportunity. This can greatly improve efficiency when many stations have small amounts of traffic because the entire channel does not need to be dedicated to one station at a time. WEP is obsolete security, and passive scanning is a WLAN discovery method. OFDMA is one of the major Wi-Fi 6 mechanisms designed to improve performance in dense multi-client environments by making more efficient use of available channel resources.<\/span><\/p>\n

                            Question 394.<\/b><\/p>\n

                            Which technology can transmit different spatial streams to multiple compatible users during the same transmission opportunity?<\/b><\/p>\n

                              \n
                            1. <\/b> WMM<\/span>
                              \n<\/span>2.<\/b> DFS<\/span>
                              \n<\/span>3.<\/b> PMF<\/span>
                              \n<\/span>4.<\/b> MU-MIMO**<\/span><\/li>\n<\/ol>\n

                              Correct Answer: 4. MU-MIMO<\/b><\/p>\n

                              Explanation:<\/b><\/p>\n

                              MU-MIMO allows multiple compatible clients to be served using different spatial streams during the same transmission opportunity. It increases aggregate efficiency by separating users in the spatial domain. OFDMA separates clients through frequency-resource allocation, while WMM, DFS, and PMF serve unrelated purposes. The actual performance benefit of MU-MIMO depends on AP capabilities, client support, RF conditions, spatial separation, and traffic demand. It should be considered one component of modern WLAN efficiency rather than a universal solution for congestion.<\/span><\/p>\n

                              Question 395.<\/b><\/p>\n

                              Which roaming enhancement is most closely associated with Fast BSS Transition?<\/b><\/p>\n

                                \n
                              1. <\/b> 802.11r<\/span>
                                \n<\/span>2.<\/b> 802.11k<\/span>
                                \n<\/span>3.<\/b> 802.11v<\/span>
                                \n<\/span>4.<\/b> 802.11e<\/span><\/li>\n<\/ol>\n

                                Correct Answer: 1. 802.11r<\/b><\/p>\n

                                Explanation:<\/b><\/p>\n

                                802.11r introduced Fast BSS Transition to reduce authentication-related delay when a client roams between BSSs. This is particularly valuable for voice and other real-time applications that may be affected by even short connectivity interruptions. 802.11k provides radio-resource information, 802.11v includes BSS Transition Management, and 802.11e introduced QoS enhancements. Fast roaming should be tested with representative production clients because endpoint support and implementation behavior vary significantly.<\/span><\/p>\n

                                Question 396.<\/b><\/p>\n

                                Which roaming enhancement can help a client identify likely neighboring APs before a roam occurs?<\/b><\/p>\n

                                  \n
                                1. <\/b> 802.11i<\/span>
                                  \n<\/span>2.<\/b> 802.11k<\/span>
                                  \n<\/span>3.<\/b> 802.11w<\/span>
                                  \n<\/span>4.<\/b> 802.11h<\/span><\/li>\n<\/ol>\n

                                  Correct Answer: 2. 802.11k<\/b><\/p>\n

                                  Explanation:<\/b><\/p>\n

                                  802.11k provides radio-resource measurement capabilities and can supply neighbor information to compatible clients. This can help reduce scanning time because the client can focus on likely roaming candidates rather than checking every possible channel. 802.11i addresses security, 802.11w management-frame protection, and 802.11h spectrum-management functions. 802.11k assists roaming but does not force a client to move. The client still makes its own roaming decision based on its internal algorithm and observed RF conditions.<\/span><\/p>\n

                                  Question 397.<\/b><\/p>\n

                                  Which security approach provides better accountability than giving all employees the same WLAN passphrase?<\/b><\/p>\n

                                    \n
                                  1. <\/b> Open authentication<\/span>
                                    \n<\/span>2.<\/b> MAC filtering only<\/span>
                                    \n<\/span>3.<\/b> 802.1X\/EAP with individual credentials<\/span>
                                    \n<\/span>4.<\/b> Static WEP<\/span><\/li>\n<\/ol>\n

                                    Correct Answer: 3. 802.1X\/EAP with individual credentials<\/b><\/p>\n

                                    Explanation:<\/b><\/p>\n

                                    802.1X\/EAP allows users or devices to authenticate with unique credentials or certificates. This provides better accountability because access can be logged and revoked individually. A single shared passphrase is harder to control once distributed widely, while MAC filtering offers weak identity assurance and WEP is obsolete. Enterprise authentication typically uses RADIUS as the backend authentication service and may integrate with directory or certificate infrastructure. Proper server-certificate validation is also important to prevent clients from trusting fraudulent authentication servers.<\/span><\/p>\n

                                    Question 398.<\/b><\/p>\n

                                    Which security mechanism most directly protects selected deauthentication frames from being forged by an attacker?<\/b><\/p>\n

                                      \n
                                    1. <\/b> WMM<\/span>
                                      \n<\/span>2.<\/b> DFS<\/span>
                                      \n<\/span>3.<\/b> OFDMA<\/span>
                                      \n<\/span>4.<\/b> Protected Management Frames**<\/span><\/li>\n<\/ol>\n

                                      Correct Answer: 4. Protected Management Frames<\/b><\/p>\n

                                      Explanation:<\/b><\/p>\n

                                      Protected Management Frames add cryptographic protection to selected robust management frames, including important deauthentication and disassociation exchanges. This makes it more difficult for an attacker to forge those frames and forcibly disconnect clients. WMM provides traffic prioritization, DFS handles radar-sensitive channels, and OFDMA improves efficiency. PMF is a key part of modern WLAN security and is required in certain newer security modes. Administrators should still verify legacy-client compatibility before enforcing it throughout a mixed-device environment.<\/span><\/p>\n

                                      Question 399.<\/b><\/p>\n

                                      Which post-deployment activity provides the strongest evidence that the installed WLAN meets the original design objectives?<\/b><\/p>\n

                                        \n
                                      1. <\/b> Validation using measured RF, capacity, roaming, and application performance<\/span>
                                        \n<\/span>2.<\/b> Reviewing the AP purchase invoice<\/span>
                                        \n<\/span>3.<\/b> Checking only controller uptime<\/span>
                                        \n<\/span>4.<\/b> Confirming that all AP LEDs are on<\/span><\/li>\n<\/ol>\n

                                        Correct Answer: 1. Validation using measured RF, capacity, roaming, and application performance<\/b><\/p>\n

                                        Explanation:<\/b><\/p>\n

                                        Post-deployment validation compares the real installed WLAN with the measurable requirements established during design. Depending on the environment, this may include RSSI, SNR, channel utilization, retries, channel reuse, roaming behavior, throughput, latency, and application performance. Representative production clients should be included where client behavior matters. Controller uptime and AP LEDs show that equipment is powered and operational but do not prove that users receive the required performance. Validation closes the design cycle by confirming that the WLAN actually meets business and technical objectives.<\/span><\/p>\n

                                        Question 400.<\/b><\/p>\n

                                        A WLAN works well when only a few clients are active but becomes slow when hundreds of users connect, even though RSSI and SNR remain good. What is the most appropriate first area to investigate?<\/b><\/p>\n

                                          \n
                                        1. <\/b> AP mounting color<\/span>
                                          \n<\/span>2.<\/b> DNS domain naming<\/span>
                                          \n<\/span>3.<\/b> Certificate subject formatting only<\/span>
                                          \n<\/span>4.<\/b> Airtime capacity, channel utilization, contention, and channel reuse**<\/span><\/li>\n<\/ol>\n

                                          Correct Answer: 4. Airtime capacity, channel utilization, contention, and channel reuse<\/b><\/p>\n

                                          Explanation:<\/b><\/p>\n

                                          The fact that performance degrades only under heavy load strongly suggests a capacity problem rather than inadequate coverage. Good RSSI and SNR show that clients receive usable signals, but they do not indicate how much airtime remains. Administrators should examine channel utilization, active-client density, co-channel contention, retry rates, channel width, application demand, and spectrum reuse. High-density WLANs are limited by shared airtime, so strong signal alone cannot guarantee good performance. Capacity should therefore be designed and validated independently from basic coverage.<\/span><\/p>\n

                                           <\/p>\n","protected":false},"excerpt":{"rendered":"

                                          View Full CWNP CWNA-109 Exam Dumps and Practice Test Dumps   Question 381. Which 802.11 mechanism allows a station to determine whether the wireless medium is currently busy by directly sensing RF activity? Physical carrier sensing 2. Virtual carrier sensing 3. DHCP discovery 4. ARP inspection Correct Answer: 1. Physical carrier sensing Explanation: Physical carrier […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":[],"categories":[1648,1647],"tags":[],"_links":{"self":[{"href":"https:\/\/www.examlabs.com\/certification\/wp-json\/wp\/v2\/posts\/18072"}],"collection":[{"href":"https:\/\/www.examlabs.com\/certification\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.examlabs.com\/certification\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.examlabs.com\/certification\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.examlabs.com\/certification\/wp-json\/wp\/v2\/comments?post=18072"}],"version-history":[{"count":2,"href":"https:\/\/www.examlabs.com\/certification\/wp-json\/wp\/v2\/posts\/18072\/revisions"}],"predecessor-version":[{"id":18074,"href":"https:\/\/www.examlabs.com\/certification\/wp-json\/wp\/v2\/posts\/18072\/revisions\/18074"}],"wp:attachment":[{"href":"https:\/\/www.examlabs.com\/certification\/wp-json\/wp\/v2\/media?parent=18072"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.examlabs.com\/certification\/wp-json\/wp\/v2\/categories?post=18072"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.examlabs.com\/certification\/wp-json\/wp\/v2\/tags?post=18072"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}