Huawei H12-811_V2.0 - HCIA-Datacom V2.0

The statement is incorrect because RIP is a distance-vector routing protocol, whereas OSPF and IS-IS are link-state routing protocols.

According to the HCIA-Datacom routing protocol material, distance-vector protocols exchange routing information with neighboring routers. RIP uses hop count as its routing metric to determine the distance to destination networks.

Link-state protocols operate differently. Routers establish neighbor relationships and exchange Link State Advertisements (LSAs), which describe their interfaces, connected networks, and topology information.

Each router uses the collected link-state information to build a link-state database and calculate the best paths using a shortest-path algorithm.

OSPF and IS-IS use this link-state approach, but RIP does not.

Therefore, although the first part of the statement correctly describes link-state routing behavior, including RIP among link-state protocols makes the complete statement FALSE.

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In OSPF, the packet type used to request specific link-state advertisements from a neighbor is the Link State Request (LSR) packet. Therefore, option B is correct. During database synchronization, OSPF neighbors first discover each other with Hello packets, then exchange summaries of their databases using Database Description (DD) packets. If one router finds that it is missing certain LSAs or has older versions, it sends an LSR packet to request the needed LSAs from its neighbor.

The neighbor then responds with a Link State Update (LSU) packet containing the requested LSAs. Finally, the receiving router confirms proper receipt with a Link State Acknowledgment (LSAck) packet. HCIA-Datacom emphasizes understanding the roles of these five OSPF packet types because they are central to neighbor formation, adjacency establishment, and LSDB synchronization. This question specifically tests whether the learner can distinguish between the request packet (LSR) and the update packet (LSU). The router does not use a DD packet to request detailed LSA content; DD packets provide database summaries, while LSR packets explicitly request the LSAs that are needed.

In a WAC + Fit AP architecture, the WAC (Wireless Access Controller) centrally manages and controls the Fit APs, so option A is correct. Service configurations such as SSIDs, security policies, radio parameters, and access control are generally delivered from the WAC to the APs. The Fit AP mainly forwards wireless user traffic and executes the configuration issued by the controller.

Option D is also correct because a Fit AP provides 802.11 wireless access for stations (STAs) and serves as a bridge between the wireless side and the wired network. This is one of its basic roles in enterprise WLAN deployment. Option B is incorrect because users or administrators do not normally need to log in to each Fit AP individually to configure wireless services; centralized management by the WAC is the whole advantage of this architecture. Option C is incorrect because CAPWAP communication between the WAC and AP does not require Layer 2 adjacency; the WAC and AP can communicate over Layer 3 as long as IP connectivity exists. HCIA-Datacom emphasizes centralized configuration, simplified operations, and scalable deployment as key benefits of WAC + Fit AP networking.

The address 224.0.0.1/24 cannot be configured as a normal host IP address by default because it belongs to the Class D multicast address range. IPv4 multicast addresses range from 224.0.0.0 to 239.255.255.255 and are reserved for multicast group communication rather than assignment to host interfaces as ordinary unicast addresses. Therefore, option D is correct.

The other three options are all private unicast address ranges and can be configured on hosts in private networks. 10.0.0.1/8 belongs to the 10.0.0.0/8 private range, 172.16.1.1/16 belongs to the 172.16.0.0/12 private range, and 192.168.1.1/24 belongs to the 192.168.0.0/16 private range. These are commonly used in enterprise and campus networks. HCIA-Datacom teaches that host IP address planning must distinguish between unicast, multicast, loopback, broadcast, and other special-purpose ranges. Multicast addresses identify multicast groups and are processed differently by hosts and network devices, so they are not valid default host addresses for ordinary end-to-end IP communication.

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.

For two directly connected edge networks to communicate through intermediate routing, each end router must have a route to the remote destination network pointing to the correct next hop on the transit link. Since 10.0.0.0/24 is directly connected to R1 and 20.1.1.0/24 is directly connected to R3, R1 needs a route to 20.1.1.0/24, and R3 needs a route to 10.0.0.0/24.

Option A is correct because it configures on R1 a static route to the remote network 20.1.1.0/24 using next hop 10.0.0.2, which is the neighbor toward the transit path. Option D is correct because it configures on R3 a static route to the remote network 10.0.0.0/24 using next hop 20.1.1.1, which is the proper adjacent forwarding address in that direction. Option B is incorrect because a router cannot use a next hop that belongs to the remote destination network but is not directly reachable as a valid immediate forwarding address in this topology. Option C is also incorrect because the specified next hop is not the correct adjacent next-hop address for R3. HCIA-Datacom stresses that static routes must always point to a reachable next hop or outbound interface.

Interface-based VLAN assignment determines the VLAN associated with an Ethernet frame according to the configuration of the receiving interface.

When an access interface receives an untagged frame, the switch assigns the frame to the VLAN specified by its Port VLAN ID (PVID).

In this scenario, the administrator forgets to configure the PVID of GE1/0/1 on SW1. Consequently, the interface retains its default PVID of VLAN 1.

PC1 sends untagged Ethernet frames through GE1/0/1, so those frames enter VLAN 1. Meanwhile, PC2 belongs to VLAN 2.

Because VLAN 1 and VLAN 2 represent separate Layer 2 broadcast domains, the switch does not directly forward traffic between them.

Without additional inter-VLAN routing or changes to VLAN membership, PC1 cannot communicate with PC2.

Therefore, the statement is FALSE.

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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.

This statement is true. When a device has multiple routes to the same destination prefix, route selection is based first on the longest prefix match, and when prefix length is the same, the device compares the route preference or administrative priority associated with each routing source. On Huawei devices, a direct route has a better preference than a static route, so the direct route is selected first when both routes have the same destination and mask.

A direct route is generated automatically when an IP address is configured on an interface and that interface is Up. Because the destination network is directly connected, this route is considered more trustworthy and efficient than a manually configured static route pointing to the same prefix. HCIA-Datacom uses this principle to explain route selection, routing-table generation, and troubleshooting cases where a configured static route does not appear as the active route because a direct or dynamic route has higher priority. This is a basic but important concept in IP forwarding and helps engineers correctly interpret routing tables on Huawei routers and Layer 3 switches.

In the standard TCP/IP forwarding model, transport-layer headers such as TCP and UDP headers are added by the source host and are mainly interpreted by the destination host. Routers that forward packets between the source and destination operate primarily at the network layer, using the destination IP address in the IP header to make forwarding decisions. Therefore, under normal routing behavior, routers do not process transport-layer header information when deciding how to forward packets.

This is a key concept in layered communication. The source host encapsulates application data with a transport-layer header, then with an IP header, and finally with a data-link header. Each router along the path removes only the Layer 2 frame header, checks the Layer 3 destination IP information, decrements TTL, recalculates the IP header checksum when required, and forwards the packet. The transport-layer content remains unchanged in normal forwarding. HCIA-Datacom uses this principle to explain end-to-end communication and layer responsibilities. Although advanced devices may inspect higher-layer information for security or policy purposes, standard router forwarding in the basic TCP/IP model does not depend on transport-layer processing.