H12-811_V2.0 Exam Dumps - Huawei HCIA-Datacom Questions and Answers

This statement is false because the receiver is one of the fundamental elements of communication. In basic communication theory, a complete communication process requires at least four essential elements: the sender , the information or message content , the transmission medium or channel , and the receiver . If the receiver is missing, communication cannot be completed because there is no endpoint to accept, interpret, or respond to the transmitted information.

In datacom networks, this concept maps directly to real networking scenarios. A source host generates data, the data is carried over some medium such as copper, fiber, or wireless, and a destination host receives the data. Network devices such as switches and routers assist the forwarding process, but the fundamental communication model still includes both communicating endpoints. HCIA-Datacom emphasizes the complete sender-to-receiver process when introducing network communication basics, protocol encapsulation, and forwarding. Therefore, excluding the receiver from the communication elements is conceptually incorrect. The correct understanding is that sender, receiver, information content, and channel together form the essential basis of communication.

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When multiple static routes exist to the same destination prefix and all next hops are reachable, the device selects the route with the highest priority , which on Huawei devices means the lowest preference value . In this question, all four static routes point to the same destination network 20.0.0.0/30, but they have different preference values.

The route through 10.1.1.2 uses the default static route preference , which is 60 on Huawei devices. The route through 10.1.2.2 has a preference of 70 , the route through 10.1.3.2 has a preference of 50 , and the route through 10.1.4.2 has a preference of 100 . Since 50 is the lowest value among them, the route via 10.1.3.2 is preferred and installed in the routing table. Therefore, option D is correct. HCIA-Datacom emphasizes that when prefix length is identical, route preference determines which route is active. This principle is widely used in route backup design, where primary and floating backup static routes are configured using different preference values to control failover behavior.

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The protocol that cannot directly modify device configurations such as interface IP addresses or device names is SFTP , so option C is correct. SFTP is a secure file transfer protocol that runs over SSH and is mainly used to upload, download, and manage files between a client and a network device. It is commonly used for tasks such as transferring configuration files, system software, patches, or log files, but it does not itself provide an interactive or structured configuration modification mechanism.

By contrast, STelnet allows secure remote CLI login, through which an administrator can directly enter commands to change device settings. NETCONF is specifically designed for network configuration management and can modify configurations in a structured manner. SNMP can also modify certain managed object values through write operations when permissions and MIB support allow it, although in practice it is used more often for monitoring. HCIA-Datacom distinguishes between management-plane protocols based on their roles: interactive access, structured configuration, monitoring, and file transfer. This question checks whether the learner can identify SFTP as a file transfer tool rather than a direct configuration protocol.

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A /28 subnet mask corresponds to 255.255.255.240, which means each subnet contains 16 IP addresses . The subnet boundaries in the last octet increase in steps of 16: 0, 16, 32, 48, 64, 80, 96, 112, 128, 144, 160, and so on. The host address 192.168.1.147 falls within the subnet range 192.168.1.144 to 192.168.1.159 .

In that subnet, the network address is 192.168.1.144, the usable host range is 192.168.1.145 through 192.168.1.158, and the broadcast address is 192.168.1.159. Therefore, option C is correct. Option D is the first usable host address, not the broadcast address. Option A is just another usable host address. Option B would be the broadcast address only for a /24 network, not for a /28. HCIA-Datacom requires learners to master subnetting because it is essential for IP planning, gateway deployment, route summarization, and troubleshooting Layer 3 communication issues in campus and enterprise networks.

This statement is false because although Area 0 is indeed the backbone area , the statement about the area ID range is incorrect. In OSPF, the area ID is a 32-bit value , which can be represented either in decimal format or in IPv4 address format such as 0.0.0.0. It is not limited to the numeric range 0 to 255 .

For example, an area can be configured as 0, 1, 100, or in dotted-decimal form such as 0.0.0.1 or 0.0.0.10, depending on implementation and configuration style. HCIA-Datacom teaches that OSPF uses hierarchical area design to improve scalability, reduce SPF calculation scope, and optimize LSA flooding. The backbone area , which is Area 0, serves as the transit area connecting all non-backbone areas in a standard OSPF design. Therefore, the second part of the statement is correct, but the first part is wrong, making the entire statement false. This question tests whether the learner understands both the function of Area 0 and the actual format of OSPF area identifiers.

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A /27 subnet mask is 255.255.255.224, which means each subnet contains 32 IP addresses. The subnet increments in blocks of 32 in the last octet: 0, 32, 64, 96, 128, 160, 192, 224. The address 192.168.1.200/27 belongs to the subnet 192.168.1.192/27.

For this subnet, the network address is 192.168.1.192, the broadcast address is 192.168.1.223, and the valid host range is from 192.168.1.193 to 192.168.1.222. Therefore, 192.168.1.221/27, 192.168.1.193/27, and 192.168.1.222/27 are all valid host addresses in the same subnet and are reachable at Layer 2 without routing. That makes A, C, and D correct.

Option B is not correct because 192.168.1.192/27 is the network address of the subnet and cannot be assigned to a host by default. This question checks IP subnetting and the ability to identify valid hosts within the same broadcast domain.

This statement is true . In the leader AP networking architecture, one AP acts as the leader AP , taking on controller-like functions similar to those of a WAC for a small or medium-sized WLAN deployment. It can centrally manage other Fit APs and deliver unified wireless configurations such as SSIDs, security settings, and radio parameters. CAPWAP is used for management and control communication between the leader AP and the managed Fit APs.

This architecture is useful in scenarios where deploying a dedicated WAC is unnecessary or uneconomical, but centralized AP management is still desired. It provides a balance between simplicity and control and is commonly used in branch offices, small campuses, and similar environments. HCIA-Datacom explains leader AP networking as an intermediate solution between fully autonomous AP deployment and full WAC + Fit AP enterprise architecture. The key point is that the leader AP behaves as the management node for the other APs and enables unified configuration and control. Therefore, the statement correctly describes both the role of the leader AP and the use of CAPWAP in this architecture.

Wi-Fi 7 supports operation in the 2.4 GHz , 5 GHz , and 6 GHz frequency bands, so options A , C , and D are correct. These three bands together provide flexible coverage and capacity options. The 2.4 GHz band offers better propagation and wider coverage, while the 5 GHz and 6 GHz bands provide more channels, higher capacity, and better support for high-speed, low-latency services.

Option B , 9.6 GHz , is incorrect because it is not a Wi-Fi 7 operating band. HCIA-Datacom WLAN content highlights Wi-Fi 7 as a major advancement in wireless performance, bringing improvements in throughput, channel usage, spectrum efficiency, and latency characteristics. The addition and use of the 6 GHz band is especially important because it expands available spectrum resources and helps reduce contention in dense wireless environments. In practical enterprise WLAN design, understanding supported frequency bands is essential for channel planning, interference control, device compatibility assessment, and service optimization. This question checks whether the learner can correctly identify the standard operating bands used by modern Wi-Fi 7 networks.

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The correct answer is C. In the command output, the AP state is shown as ver-mismatch. This state directly indicates a version mismatch between the AP and the WAC. In Huawei WLAN deployment, a Fit AP must use a software version that is compatible with the WAC version. If the versions do not match, the AP may be discovered by the WAC and appear in the AP list, but it cannot successfully complete the online process.

Option A is incorrect because blacklist-related failures are displayed with blacklist-related status information, not ver-mismatch. Option B is also incorrect because authentication failures normally generate authentication-related fault indications. Option D is incorrect because configuration initialization failure would not be identified by the specific ver-mismatch state.

HCIA-Datacom troubleshooting knowledge emphasizes reading AP online states carefully. Common causes of AP online failure include IP address acquisition failure, CAPWAP tunnel establishment failure, insufficient licenses, authentication problems, and version mismatch. When the state explicitly shows ver-mismatch, the troubleshooting direction is clear: check AP and WAC software compatibility and upgrade or align the software version as needed.

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In TCP, the acknowledgment number indicates the next byte that the receiver expects to receive. In the figure, PC1 sends a TCP segment to PC2 with sequence number = a+22 and payload length = 22 bytes . Since TCP sequence numbers count bytes, the last byte carried in this segment corresponds to sequence number a+43 . Therefore, after PC2 successfully receives this data, it sends back an ACK indicating that the next expected byte is a+44 .

That is why option B is correct. This is a standard TCP reliability mechanism. TCP does not acknowledge “packets” as units; it acknowledges the byte stream. The ACK number always points to the next byte expected from the peer. The source and destination port numbers identify the session, but the sequence and acknowledgment numbers track ordered delivery. HCIA-Datacom uses this mechanism to explain connection-oriented transport, reliable delivery, retransmission, and traffic control. Understanding how the payload length affects sequence progression is essential when analyzing packet captures and troubleshooting TCP communication problems in enterprise networks.

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