Pass Using H19-404_V1.0 Exam Dumps

An AP’s transmit power must be maintained within an appropriate range. Excessive power does not automatically improve service quality. A high-power AP can enlarge its interference domain, create co-channel or adjacent-channel interference, produce asymmetric uplink and downlink coverage, and cause sticky-client behavior because a station continues hearing an AP even when its weaker transmission cannot reliably reach that AP. Huawei states that high-power APs can interfere with adjacent APs and that radio calibration dynamically adjusts AP channels, power, and frequency bands to ensure coverage while minimizing interference.

Conversely, power that is too low creates coverage holes, weak received signal strength, low modulation rates, retransmissions, and roaming instability. When a new AP is added, neighboring APs may reduce their transmit power to limit interference. When an AP goes offline, neighboring APs may increase power to compensate for the missing coverage. The engineering objective is therefore neither maximum nor minimum power, but sufficient coverage with controlled overlap and minimum interference. Accordingly, option B is correct.

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The statement is false. An MPLS label stack is an ordered sequence of label-stack entries, with the top label processed first and the bottom identified by the Bottom-of-Stack bit. However, the MPLS architecture does not define a universal maximum of three nested labels. An MPLS forwarding operation may replace the top label, remove it, or push one or more additional labels onto the stack.

Practical label depth is constrained by device implementation, forwarding ASIC capabilities, packet size, and the number of network functions being encoded. A conventional MPLS VPN may use two labels: a transport label and a VPN label. More advanced deployments can add labels for traffic engineering, segment routing, entropy, service chaining, or hierarchical transport. This can produce stacks deeper than three entries.

Therefore, “three layers” may describe a limitation of a particular platform, software version, or deployment design, but it is not an MPLS protocol maximum. RFC 3032 defines the stack as a sequence of four-byte entries and explicitly allows one or more entries to be pushed without specifying a three-label ceiling.

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Option B is false because a station retains its original IP address during Layer 3 roaming. Preserving the IP address is essential for maintaining active application sessions when the station moves between APs associated with different service VLANs, Layer 2 domains, and gateways. Huawei’s training diagram shows the same station IP address before and after roaming, while the service VLAN changes.

When the STA initially accesses the WLAN, a Home AP or HAP is selected for it. After the STA roams to a Foreign AP, the new AP obtains the station information and establishes the required forwarding relationship with the HAP. In direct-forwarding implementations, the STA’s traffic is encapsulated and forwarded to the HAP, which preserves access through the original network and gateway.

Therefore, A and C accurately describe HAP-based Layer 3 roaming. Option D is also correct: the APs use the same SSID and authentication mode but different service VLANs. The station’s IP address does not change, so B is the false statement.

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AR routers support registration query center–based deployment, email-based deployment, and DHCP Option 148–based deployment. In registration query center deployment, the router obtains basic network connectivity, resolves or contacts Huawei’s registration service, retrieves the address and port of iMaster NCE, and then initiates registration. Huawei identifies AR routers, firewalls, switches, and APs as applicable devices for this method.

Email-based deployment is a major SD-WAN ZTP method for AR routers operating as CPEs. An administrator creates the site and ZTP configuration on iMaster NCE and sends a deployment URL to the onsite engineer. After the URL is opened and the parameters are written to the router, the device connects to the WAN and automatically registers with the controller.

DHCP Option 148 can provide the controller’s southbound IP address and port number to an IPv4 AR router, enabling automatic registration. Barcode scanning through the CloudCampus APP is specifically presented as an AP onboarding method, not an AR-router deployment method. Therefore, A, C, and D are correct.