Free Practice Questions for Huawei H12-821_V1.0 Exam

Comprehensive and Detailed Step-by-Step Explanation:

Routing Table Structure:

Routers maintain a local core routing table and separate protocol routing tables for OSPF, BGP, etc.

The local core routing table stores optimal routes selected based on metrics, protocol preferences, and administrative distances.

Fields in the Core Routing Table:

Destination Address (A): Indicates the destination network or host.

Routing Protocol Preference (B): Determines the priority of routing protocols (e.g., OSPF > RIP).

Routing Protocol (D): Specifies the protocol (e.g., OSPF, BGP) that contributed the route.

Inbound Interface: This is stored in the protocol-specific routing table but not in the local core table.

In VRRP HSB (Hot Standby Backup) mode for WLAN deployments (typically between ACs or access controllers), backup of critical data ensures fast failover and minimal service disruption.

A. Real-time backup – Supported. Configuration and session information are synchronized in real-time between the active and standby ACs.

B. Scheduled synchronization – Not supported. HSB requires instant synchronization, not based on a scheduled time.

C. Batch backup – Supported. Some types of less time-sensitive data (e.g., logs or counters) may be backed up in batches.

D. Cloud backup – Not part of HSB functionality. Cloud backup is a separate mechanism, typically used for archival purposes, not real-time failover.

Reference from Huawei HCIP-Datacom-Core Technology Study Guide:

“VRRP HSB mode supports real-time and batch backup between ACs to protect WLAN services. Scheduled and cloud backups are not part of HSB functionality.”

(Chapter: WLAN Reliability – Section: AC Redundancy and HSB Mechanism)

Comprehensive and Detailed Step-by-Step Explanation:

Interface ID in IPv6:

The interface ID is the last 64 bits of an IPv6 address, and it uniquely identifies an interface within a subnet.

It can be generated in three ways:

Manually Configured: Explicitly assigned by an administrator.

System-Generated: The operating system assigns a random or pseudo-random value.

EUI-64 Standard: Generated based on the MAC address of the interface.

Correct Statement:

IPv6 supports all three methods for generating interface IDs.

Comprehensive and Detailed Step-by-Step Explanation:

Analysis of VRRP Configuration:

Option A (Preemption): Correct. The output explicitly states that preemption is enabled.

Option C (Authentication): Correct. Authentication is enabled using MD5.

Option D (Group ID): Correct. The VRRP group ID is explicitly stated as 1.

False Statement:

Option B (mVRRP Group): The output does not indicate this is an mVRRP (Multicast VRRP) group. This feature must be explicitly configured and is not enabled by default.

Comprehensive and Detailed Step-by-Step Explanation:

1. Features of Wi-Fi 6:

Wi-Fi 6 (802.11ax) introduces several new technologies to improve network efficiency, reduce latency, and optimize power usage:

OFDMA (Orthogonal Frequency Division Multiple Access): Allows multiple devices to transmit simultaneously, improving concurrency.

TWT (Target Wake Time): Reduces power consumption by scheduling communication times for devices.

High Bandwidth: Supports up to 9.6 Gbps, significantly faster than Wi-Fi 5.

2. Why Zero Latency is Incorrect:

While Wi-Fi 6 reduces latency compared to earlier standards, zero latency is not achievable due to inherent delays in network communication.

The statement "Realizes zero latency" is misleading and technically inaccurate.

3. Analysis of Each Option:

Option A: Uses OFDMA technology to achieve high concurrency.

Correct (True Statement).

OFDMA is a core feature of Wi-Fi 6 that improves concurrent communication.

Option B: Realizes zero latency, ensuring efficient service running.

Incorrect (False Statement).

Wi-Fi 6 reduces latency but cannot eliminate it entirely.

Option C: Provides high bandwidth, up to 9.6 Gbps.

Correct (True Statement).

Wi-Fi 6 supports a theoretical maximum bandwidth of 9.6 Gbps.

Option D: Uses TWT technology to reduce terminal power consumption.

Correct (True Statement).

TWT schedules communication times, allowing devices to enter low-power states and conserve battery life.

4. Summary:

The false statement is B, as Wi-Fi 6 does not achieve zero latency.

By default, BGP does not automatically summarize imported routes. Route summarization must be explicitly configured using the summary or similar commands ​.

The correct command for configuring the VRRP (Virtual Router Redundancy Protocol) preemption delay is vrrp vrid 1 preempt-delay 20. This command sets the delay before a higher-priority VRRP router preempts the master role, ensuring stable operation during network transitions ​.