Pass the Huawei HCIA-Datacom H12-811_V1.0 Questions and answers with CertsForce

Comprehensive and Detailed Explanation:

IPv6 supports several extension headers:✅ Fragment Extension Header → Handles packet fragmentation.✅ Destination Options Header → Stores information for destination nodes.✅ Hop-by-Hop Options Header → Used for router-specific instructions.

❌ Incorrect Option:

VLAN extension header does not exist in IPv6. VLAN tagging is handled at Layer 2 (Ethernet).

✅ Reference: HCIA-Datacom Network Principles Guide – IPv6 Packet Structure

An access port is a switch port assigned to a single VLAN and used to connect end devices (such as PCs or printers).

Access ports do not send VLAN tags. They remove the VLAN tag before forwarding frames to the connected device because most end devices do not support VLAN tagging.

Option A (Incorrect): Tagged frames are sent only by trunk ports, not access ports.

Option B (Correct): The access port strips the VLAN tag before forwarding the frame to ensure compatibility with non-VLAN-aware devices.

Option C (Incorrect): VLAN tags are not exchanged between inbound and outbound ports.

Option D (Incorrect): The access port does not attach PVID information to the frame when sending it out.

Thus, the correct answer is B.

In Huawei’s VRP, the default preference value for OSPF routes is generally 10, but this value can be adjusted based on configuration requirements. Therefore, it is not necessarily always set to 10, as network administrators may alter the preference to prioritize different routes. This flexibility allows customization based on the network's specific routing needs​.

Detailed Explanation:In a "one-armed routing" setup, a router with sub-interfaces can handle inter-VLAN routing by logically segmenting traffic within a single physical interface. In this configuration, each department (Administration and Finance) is assigned a different VLAN with separate sub-interfaces on Router R1.

In such a setup, communication between different VLANs (i.e., inter-VLAN routing) is handled by the router, even without Proxy ARP enabled. The router can directly route packets between the VLANs as it is aware of the different networks and performs Layer 3 forwarding based on the IP address of each VLAN's sub-interface.

Thus, even if ARP Proxy is disabled, devices in the Administration and Finance departments can communicate through the router because inter-VLAN routing takes place at Layer 3 without relying on ARP proxy functionality​​​.

The Forward Delay timer in STP helps prevent temporary loops by setting a delay for ports transitioning through Listening and Learning states before reaching the Forwarding state. This wait period ensures that all switches have updated topology information, reducing the risk of broadcast storms or loops​.

Device Interconnection Requirements:

Device interconnection (such as point-to-point links) requires only two IP addresses: one for each device.

A subnet mask of /30 (255.255.255.252) provides four total addresses (2 usable, 1 network, 1 broadcast).

Efficiency:

Using a /30 subnet avoids wasting IP addresses, making it ideal for point-to-point links.

Why Other Options Are Incorrect:

B (32): /32 is used for single-host IP addresses, not links.

C (24): /24 is excessive for point-to-point links, providing 254 usable addresses.

D (16): /16 provides 65,534 addresses, which is highly inefficient.

References: HCIA-Datacom V1.0 Certification Guide, Chapter 3: IP Addressing.

Detailed Explanation:DNS (Domain Name System) is responsible for translating human-readable domain names (like www.example.com) into IP addresses, enabling devices to locate services on a network. (Reference: HCIA-Datacom Training Material, DNS Function and Protocol Overview)

LSI (A): There is no such packet type in OSPF.

HELLO (B): These packets are used for neighbor discovery and maintaining adjacency, not for requesting LSAs.

LSACK (C): Link-State Acknowledgment (LSAck) packets confirm the receipt of LSAs but do not request missing ones.

LSR (D): Link-State Request (LSR) packets are specifically used by routers to request missing LSAs from their neighbors.

Thus, the correct answer is D (LSR).