Free and Premium Cisco 300-425 Dumps Questions Answers

 Large cases of liquid materials can cause higher signal loss compared to dry goods due to the way radio frequency (RF) waves interact with liquid, which can absorb and reflect the signals more than dry materials.

Mobility domains and mobility groups are concepts used in wireless networking to manage client roaming and security contexts. When Wireless LAN Controllers (WLCs) are in the same mobility domain, they can communicate with each other, allowing clients to roam seamlessly between APs managed by different controllers. Mobility groups further refine this by constraining the distribution of a client’s security context, which includes authentication and encryption keys, and by managing AP failover between controllers. This ensures that a client can maintain a secure and stable connection as they move throughout the network.

To support high availability, the design must include redundant Wireless LAN Controllers (WLCs) to ensure service continuity in case of a failure. Additionally, having a high availability pair with one WLC holding a valid AP count license ensures that all APs can remain connected and services continue without interruption during failover.

 Mobility tunnels between Cisco Wireless LAN Controllers (WLCs) use UDP port 16666 for control messages and UDP port 16667 for data traffic. If EPING is failing, it indicates that the necessary ports are not open. Allowing UDP port 16666 through the firewall would enable the control messages required for establishing the mobility tunnels.

IEEE 802.11ac Wave 2 APs are backward compatible with 802.11a/n clients, allowing these devices to connect and communicate with the newer APs, albeit at their respective maximum supported speeds.

 During a client roaming event, the Wireless LAN Controller (WLC) is responsible for communicating the new Layer 2 Endpoint ID (EID) mapping of a wireless supplicant to the fabric domain. The WLC acts as a mobility orchestrator within the Cisco Digital Network Architecture (DNA) to ensure seamless roaming and connectivity. References: Designing Cisco Enterprise Wireless Networks (ENWLSD 300-425)

The command debug mobility handoff enable is used to validate the mobility control packets between Wireless LAN Controllers (WLCs). This command enables debugging of the handoff process, which is critical for ensuring seamless client roaming between controllers. When WLCs are separated by firewalls, it is essential to confirm that mobility control packets can traverse these firewalls without being dropped or rejected. The debug mobility handoff enable command allows network administrators to monitor the handoff process and troubleshoot any issues that may prevent successful client roaming.

To support VoWLAN services and provide roaming recommendations to supported voice clients without impacting non-VoWLAN clients, the feature that should be enabled on the VoWLAN SSID is 802.11k neighbor lists. This feature allows APs to provide information about neighboring APs that are candidates for roaming, which helps clients make better decisions about when and where to roam. References := CCNP Enterprise Wireless Design ENWLSD 300-425 and Implementation ENWLSI 300-430 Official Cert Guide Premium Edition and Practice

In high-density environments, such as stadiums or auditoriums, APs are often mounted under the seats to provide a controlled cell size with attenuation. This placement helps to manage the RF environment by providing attenuation of 6 dB to 20 dB, which can reduce co-channel interference and improve the user experience by ensuring a strong signal and minimizing noise from other cells.

In a global mesh deployment, using redundant controllers in the least restrictive regulatory domain ensures the highest number of channels available for backhaul. This design accommodates the varying regulatory constraints of different regions by adhering to the domain with the most lenient channel availability.

To reduce co-channel interference, it’s beneficial to decrease channel bonding, which will increase the number of non-overlapping channels available. Reducing the power of the APs can also help minimize interference by reducing the range of each AP’s signal, thereby reducing the chance of overlap.

In a hospital setting, the kitchen is a common source of 2.4 GHz RF noise due to the use of microwave ovens which operate on the same frequency. X-ray radiography equipment, while primarily using higher frequency ranges, can also contribute to RF noise in both the 2.4 GHz and 5 GHz bands due to electronic components and shielding inefficiencies. References: CCNP Enterprise Wireless Design ENWLSD 300-425 and Implementation ENWLSI 300-430 Official Cert Guide.

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In a high availability setup with Cisco 5508 Wireless LAN Controllers, the standby controller can be accessed via the console connection and the service port interface. The console provides direct access, while the service port interface allows for network-based access to the standby unit for management purposes.

The issue where APs failed over to the tertiary controller instead of the secondary controller during a controller failure is likely due to the secondary controller being at capacity. When a controller reaches its maximum capacity, it cannot accept any additional APs, causing them to failover to the next available controller in the high availability configuration.

 LAG-based redundancy is chosen for its ability to provide continuous connectivity as long as one port in the LAG is operational (B), utilize the full bandwidth capacity of all the links in the LAG (E), and allow for the grouping of ports into multiple LAGs for increased redundancy and bandwidth (F). References: CCNP Enterprise Wireless Design ENWLSD 300-425 and Implementation ENWLSI 300-430 Official Cert Guide.

To address the sticky client problem, setting an RSSI (Received Signal Strength Indicator) threshold can help. This configuration will prompt clients to roam to a better AP when their signal strength falls below the set threshold, thus enhancing the roaming experience and ensuring clients are connected to the AP with the strongest signal available.

The survey model described is used for location services, VoIP, data, and video. The placement of APs on exterior walls, building corners, and major turns helps ensure consistent coverage and signal strength for a variety of applications, including precise location tracking and high-quality voice and video communications. References: Designing Cisco Enterprise Wireless Networks (ENWLSD 300-425)

When identifying network requirements, it’s important to consider the number of wireless devices that will need access to ensure sufficient capacity and coverage. The business type can influence the types of applications and services that will be used, which in turn affects the network design.

When configuring high availability on an access point, a network engineer can configure a maximum of two controllers. One serves as the primary controller, and the other serves as the secondary controller.

 In environments with high client density, deploying APs for 5 GHz coverage is recommended due to the larger number of non-overlapping channels available, which can support higher data rates and client capacity. Disabling the 2.4 GHz radios on some APs can reduce interference and improve overall network performance.

 Cisco 3800 Series APs support higher speeds provided by IEEE 802.11ac Wave 2, which Fast Ethernet switches cannot fully support. Replacing them with mGig or gigabit switches with 10G uplinks will ensure the infrastructure can handle the increased data rates. The CAT 6A standard supports these speeds, so there’s no need to replace the wiring if it’s already CAT 6A.

For an effective office site survey, it’s recommended to: A. Use a battery pack to power APs - This allows for mobility and testing in various locations without relying on fixed power sources. B. Use a drawing of the office space to mark AP and client placements - This helps in planning the optimal locations for AP installation. F. Use APs with built-in antennas - They are commonly used for site surveys as they represent the typical deployment scenario.

In a high-density environment like an auditorium, where APs are in close proximity and a large number of devices are connected, the RF profile is used to adjust the radio frequencies of the APs to minimize co-channel interference. The RF profile allows for the configuration of power levels, channel width, and channel assignment to optimize wireless performance and reduce interference. References: CCNP Enterprise Wireless Design ENWLSD 300-425 and Implementation ENWLSI 300-430 Official Cert Guide Premium Edition and Practice

 Before replacing old APs with IEEE 802.11ac-capable APs, it is crucial to check the software version of the wireless LAN controller. The controller’s firmware must support the newer standards and capabilities of 802.11ac APs. An outdated software version may not support the advanced features and performance enhancements offered by 802.11ac technology, leading to compatibility issues and suboptimal network performance.

When using the Cisco Prime Infrastructure Planning Tool for deploying a Greenfield 802.11n network with data, voice, location awareness, and APs equipped with WSSI modules, selecting ‘Voice’ will ensure that the tool accounts for the additional bandwidth requirements of voice applications which have strict QoS requirements. Choosing ‘Location’ will allow the tool to consider the need for more precise location tracking capabilities which typically require additional APs for triangulation purposes. References := CCNP Enterprise Wireless Design ENWLSD 300-425 and Implementation ENWLSI 300-430 Official Cert Guide Premium Edition and Practice

 The Cisco 8540 Wireless Controller is designed for large enterprise and high-density environments. It has the capacity to manage up to 6000 access points, making it suitable for a multicampus architecture that needs to accommodate 4500 access points. Its high availability features ensure that all access points can be supported on one controller setup with minimal downtime.

To optimize roaming in a wireless network with multiple controllers, it is essential to use the same WLAN name (SSID) across all controllers. This allows clients to roam seamlessly between access points managed by different controllers without having to re-authenticate or experience disconnections1.

Optimized roaming is a feature that helps mitigate sticky client behavior by assessing the client’s signal strength and proactively disconnecting clients with a signal below a predefined threshold. This encourages clients to connect to a closer AP with a stronger signal, improving the overall wireless experience in high-density areas.

 To ensure that the most critical APs at remote sites remain functional in the event of a failure, the Global AP Failover Priority feature can be used. By setting the priority of the most important APs to “critical”, these APs will be given precedence over others during a failover scenario. This allows the engineer to prioritize which APs should remain online without impacting the main site’s APs, which are set to a “high” priority.

 In a Layer 1 passive wireless site survey, the chart that indicates the ratio of interference present during the duration of the capture in the 2.4 GHz spectrum is typically a Duty Cycle chart or an Interference chart. These charts display the percentage of time that energy, possibly from interfering sources, is present on a channel. The correct answer would show fluctuations in signal levels over time, highlighting periods where interference might be affecting the channel’s clarity.

In Cisco WLC release 8.9, the controller software can scale up to 20 WLCs and 3000 APs within a single RF group. This capability allows the Radio Resource Management (RRM) algorithms to function effectively across a larger network, optimizing the wireless experience by managing the RF environment and resources across multiple controllers and access points.

 In an outdoor mesh network designed to cover sports fields, a 5 GHz, 14-dBi patch antenna is suitable for the RAP for backhaul connectivity. The higher gain and directional nature of a patch antenna help in focusing the signal over longer distances and in specific directions, which is ideal for connecting various points in a large outdoor area5.

In Cisco wireless networks, access points can be configured with failover priorities ranging from 1 to 4, with 1 being the highest priority and 4 being the lowest. An access point with priority 1 is considered critical and will be given preferential treatment in failover situations, ensuring that it reconnects to a backup controller before access points with lower priorities

The decision to configure LAG-based redundancy is influenced by the following features:

B. All interface traffic passes as long as one port is up: This ensures that the wireless LAN controller can continue to operate and manage traffic as long as at least one port in the LAG is functioning, providing a robust failover solution1.

D. Interface connection to two separate nonstacked switches is available: LAG allows for connections to multiple switches, which can provide redundancy and higher availability compared to single switch connections1.

E. Full bandwidth of all links is available: With LAG, the combined bandwidth of all active ports is available, enhancing the throughput capabilities of the wireless LAN controller1.

 Cisco Hyperlocation requires a dense deployment of access points for accurate location tracking. Adding more APs than a standard site survey suggests can meet the granular location requirements needed for Hyperlocation services. References: ENWLSD official certification guide.

To mitigate increased co-channel interference and retransmissions after adding an AP, Transmit Power Control (TPC) and Dynamic Channel Assignment (DCA) can be effective. TPC adjusts AP transmit power based on real-time analysis of the wireless environment, reducing interference by lowering power where necessary. DCA dynamically changes channel assignments based on current RF conditions to optimize performance and minimize interference.

Setting the Anchor priority for the primary controller to 1 ensures that clients connect to the primary controller first. The Anchor priority is a value assigned to each controller within a mobility group to determine the order in which clients should connect to the controllers. A lower priority value has higher precedence. Therefore, by setting the primary controller’s Anchor priority to 1, it becomes the preferred controller for client connections. If the primary controller fails, clients are then pushed to the secondary controller, which should have a higher Anchor priority value.

For handheld mobile scanners processing credit card payments, security and seamless roaming are critical. The 802.11w standard, also known as Protected Management Frames (PMF), provides enhanced security that helps prevent disconnections and issues when roaming between access points. Incorporating 802.11w in the design ensures that the scanners maintain a secure and consistent connection while moving throughout the environment. References: CCNP Enterprise Wireless Design ENWLSD 300-425 and Implementation ENWLSI 300-430 Official Cert Guide Premium Edition and Practice

 When designing a backhaul link, the mesh AP role should be set to ‘bridge’ to enable it to connect separate network segments or extend coverage to remote areas.

Devices that only support 2.4 GHz can increase congestion on this frequency band, especially in environments where multiple devices are present. This is because the 2.4 GHz band has fewer non-overlapping channels compared to 5 GHz, leading to more interference and potential performance issues.

Link Aggregation Group (LAG) allows multiple physical ports to be combined into a single logical channel. In the scenario where only one Cisco 9800-40 WLC is available and high availability is required, LAG can be used to manage port redundancy and perform load balancing between APs transparently. This ensures that if one cable fails, the others can continue to carry the traffic without any perceived downtime

Guest anchoring requires mobility tunnels to be established between the foreign and anchor WLCs. For these tunnels to function, the firewall must allow specific ports for communication. UDP port 16666 is the port used for mobility traffic in Cisco wireless networks, and if it is not allowed through the firewall, MPING and mobility tunnels will fail. References: CCNP Enterprise Wireless Design ENWLSD 300-425 and Implementation ENWLSI 300-430 Official Cert Guide Premium Edition and Practice

In a mobility group, multiple controllers should be configured with the same virtual IP address to ensure proper roaming. This virtual IP address is used by wireless clients during the roaming process to facilitate seamless mobility between controllers.

An SNR (Signal-to-Noise Ratio) less than 15 dB within the cell boundary during an AP-on-a-stick survey indicates that there is interference affecting the AP’s signal. This interference could be from another signal source that is reducing the quality of the connection, despite the signal strength being within the acceptable cell boundary of -67 dBm.

 In a mining facility, especially within mine shafts where the environment can be long and narrow, an omnidirectional antenna is typically used for a Layer 2 survey. This type of antenna radiates RF signal equally in all directions, providing coverage along the length of the shaft.

 For a pre-deployment site survey, it’s important to know the AP model to understand the capabilities and coverage pattern of the APs. Additionally, knowing the number of clients helps to design a network that can handle the expected client density.

To minimize channel utilization and interference with existing tenant networks, it’s best to use the UNII-1 channels, which are typically less congested, and stick to 20-MHz channels to provide more non-overlapping channels and reduce co-channel interference.

 When a data path mobility tunnel fails to come up, one of the troubleshooting steps is to check if the necessary ports are open and not being blocked by any firewalls in the path. Since the mobility tunnel uses CAPWAP, which operates on UDP ports 16666 (control path) and 16667 (data path), establishing a Telnet connection to the firewall on port 16666 can help determine if the control path is open and if there are any issues that need to be addressed3.

When conducting a Layer 2 site survey, it is recommended to match the survey to the worst client available. This ensures that the wireless network is designed to provide adequate coverage and performance even for the clients with the poorest capabilities, thereby ensuring a consistent user experience for all devices2.

 In the scenario described, where some APs did not failover to their secondary controller despite having sufficient licenses, the issue likely lies with the configuration of the APs to recognize the secondary controller. Since the controllers are not in a mobility group but have A records for their hostnames in DNS, this suggests that they rely on DNS for AP discovery and failover. If APs are not failing over as expected, it could be due to an incorrect IP address configured for the secondary controller on the AP or within DNS. The exhibit shows that the “Secondary Controller” field has an IP address of “10.42.89.11”, which should be verified against DNS records and actual controller settings to ensure accuracy. References := (CCNP Enterprise Wireless Design ENWLSD 300-425 and Implementation ENWLSI 300-430 Official Cert Guide Premium Edition and Practice)

 Fast Transition (FT), also known as IEEE 802.11r, is the key-caching mechanism that must be configured to speed up the reauthentication delays on the wireless infrastructure. FT allows for rapid re-authentication when roaming between access points, reducing the time required for re-establishing security keys and thus speeding up the overall process2.

For pervasive coverage in an oil terminal that supports casual web and email traffic over 5 GHz, disabling lower data rates can help improve overall network efficiency. Lower data rates can cause the network to slow down because they take up more airtime. By disabling rates below 24 Mbps, the APs can focus on providing higher throughput for users. Keeping the power assignment as auto allows the APs to adjust their power levels dynamically for optimal coverage and client performance

 When designing a network with a DMZ and an EoIP tunnel, it’s important to ensure that the data plane is encrypted to protect the data as it traverses potentially unsecured networks. Cisco IOS-XE on the Catalyst 9800 supports encryption of the data plane, which is essential for this design.