H12-891_V1.0 Exam Dumps - Huawei HCIE-Datacom Questions and Answers

Comprehensive and Detailed Explanation:

✔ The Best Protection Against MITM and Spoofing Attacks:

✅ (D) Associating DHCP Snooping with IPSG (IP Source Guard) and DAI (Dynamic ARP Inspection) provides complete protection by:

Blocking rogue DHCP servers.

Preventing MAC/IP spoofing.

Ensuring only valid clients access the network.

✔ Why Not Other Options?

❌ (A) Configuring trusted/untrusted interfaces only helps block rogue DHCP servers, but does not prevent spoofing.

❌ (B) Limiting MAC address learning prevents MAC flooding, but does not stop MITM attacks.

❌ (C) Checking the CHADDR field in DHCP Snooping helps detect spoofed requests, but does not block all MITM scenarios.

???? Reference: Huawei HCIE Datacom – Security Mechanisms for Intranet Protection

Telemetry Data Collection in Huawei Devices

Telemetry allows real-time streaming of network performance data based on predefined sampling paths. Supported sampling paths include:

✅ A. Interface statistics

Monitors real-time traffic usage, errors, and packet loss on interfaces.

✅ C. CPU information

Tracks CPU utilization and performance metrics.

✅ D. Memory information

Monitors RAM usage and system memory consumption.

Incorrect Answer:

❌ B. Information about the optical module on an interface

Telemetry does not natively support direct optical module monitoring; instead, SNMP or CLI commands like display transceiver are used.

Reference from Huawei HCIE-Datacom Documentation:

Huawei Telemetry Configuration Guide – Supported Sampling Paths

HCIE-Datacom Study Material – Network Performance Monitoring with Telemetry

802.1X Authentication Overview

802.1X is a port-based authentication mechanism used for secure network access control. It involves:

EAPoL (Extensible Authentication Protocol over LAN) communication between the client (supplicant) and the switch (authenticator).

RADIUS communication between the authenticator and the authentication server (AAA server).

✅ A. 802.1X authentication uses EAPoL to exchange authentication information.

EAPoL (Extensible Authentication Protocol over LAN) is used to send authentication packets over Ethernet (IEEE 802.3) networks.

✅ B. In EAP termination mode, the network device terminates EAP packets and re-encapsulates them into RADIUS.

The switch acts as an authentication proxy by terminating EAP sessions and converting authentication information into RADIUS format.

✅ C. EAPoL is for wired (802.3), EAPoW is for wireless (802.11).

EAPoL (EAP over LAN) is used in wired Ethernet networks.

EAPoW (EAP over Wireless) is used in Wi-Fi (802.11) networks.

✅ D. In EAP relay mode, EAP packets are encapsulated into RADIUS using EAPoR (EAP over RADIUS).

The switch does not terminate the EAP session but instead forwards EAP messages to the AAA server inside RADIUS packets.

Reference from Huawei HCIE-Datacom Documentation:

Huawei 802.1X Configuration Guide – EAPoL, EAPoW, and EAPoR

HCIE-Datacom Training Material – AAA Authentication Modes

Comprehensive and Detailed Explanation:

✔ Huawei OPS (Open Programmability System) follows RESTful API principles, using HTTP methods for device management.

✔ HTTP Methods Used in OPS:

✅ GET → Retrieves data from the device.

✅ POST → Creates new data/configurations.

✅ PUT → Replaces entire configuration objects.

✅ PATCH → Updates specific fields of a configuration object. ✅ (Correct Answer)

Since PATCH is used for modifying specific values in managed objects, the correct answer is D.

???? Reference: Huawei HCIE Datacom – RESTful API Operations in Huawei OPS

Comprehensive and Detailed Explanation:

In the given configuration:

Traffic from PC1 (192.168.1.1) is classified by ACL 2000.

Traffic is remarked with DSCP value 26 (DSCP 26).

DSCP 26 corresponds to AF31, which maps to the AF3 queue in DiffServ QoS.

DiffServ QoS Queue Mapping:

EF (Expedited Forwarding) → DSCP 46

AF4 (Assured Forwarding Class 4) → DSCP 40-47

AF3 (Assured Forwarding Class 3) → DSCP 26-31 ✅

AF2 (Assured Forwarding Class 2) → DSCP 18-23

Since DSCP 26 falls within AF3, the packets enter the AF3 queue on R2.

???? Reference: Huawei HCIE Datacom – QoS and DSCP Mapping

Understanding L3VPN over SRv6 BE Networks

???? What is L3VPN over SRv6?

Layer 3 VPN (L3VPN) allows multiple private routing domains to operate over a shared service provider backbone.

SRv6 (Segment Routing over IPv6) replaces traditional MPLS labels with IPv6 Segment Identifiers (SIDs).

Best Effort (BE) mode means that no explicit Traffic Engineering (TE) constraints are applied.

How Routing Works in This Scenario

Key Components in the Network:

PE1 & PE2 (Provider Edge routers): Connect customer networks (CE1 & CE2).

P Router (Core Router): Provides transit between PE routers over SRv6.

SRv6 SID FC00:2::1:79: Used for VPN routing at PE2 (End.DT4 function).

Step-by-Step Route Learning Process:

1️⃣ PE1 advertises the 192.168.1.0/24 VPN route to PE2 using iBGP VPNv4.

2️⃣ PE2 receives the route with next-hop 2001:DB8:1::1 (PE1).

3️⃣ PE2 installs the route with the SRv6 Prefix-SID FC00:2::1:79 (End.DT4).

4️⃣ The route is imported into the VRF using the import-route command.

Analysis of Each Answer Choice

✅ A. An IBGP peer relationship is established between PE2 and PE1, and PE2 learns the route to 192.168.1.0/24 over an IBGP peer relationship.

Correct: The routing table output confirms that PE2 receives the route via iBGP from PE1.

✅ B. The instruction type corresponding to FC00:2::1:79 is End.DT4.

Correct:

End.DT4 is an SRv6 function that represents a Layer 3 VPN endpoint (VRF routing).

PE2 uses End.DT4 to process VPN traffic for 192.168.1.0/24.

✅ C. PE2 imports the route 192.168.1.0/24 through the import-route command.

Correct:

The import-route command allows BGP-learned routes to be added to the local routing table (VRF).

❌ D. The router ID of the BGP process on the P router is 1.0.0.6. (Incorrect Statement)

Incorrect:

The P router is a transit router and does NOT run BGP for VPNv4 routes.

The router ID of PE2 is 1.0.0.11, and the route originator is 1.0.0.2 (likely PE1).

P routers in an SRv6 BE network do NOT need BGP router IDs.

Final Answer: D (The router ID of the BGP process on the P is 1.0.0.6.)

✅ Reference: Huawei HCIE-Datacom Guide – SRv6 L3VPN Routing and End.DT4 Function

Real-World Application:

Service Provider Networks: Uses SRv6 to replace MPLS in large-scale VPN deployments.

5G Transport Networks: Implements SRv6 L3VPN for high-speed, low-latency services.

For SRv6 (Segment Routing over IPv6) deployment on a bearer WAN, the following are essential:

IGP (OSPFv3 or IS-IS): Required for SID advertisement and SRv6 route computation → ✅

BGP: Required when deploying inter-domain SRv6 or for control plane distribution of VPN/service routes → ✅

Not required:

MPLS: SRv6 replaces MPLS labels with IPv6-based SIDs → ❌

BGP-LU: Used in MPLS-based inter-AS scenarios, not applicable to SRv6 → ❌

Correct answers: B, C

Comprehensive and Detailed In-Depth Explanation:

In NETCONF (Network Configuration Protocol), the < config > operation can include operation attributes to specify how configuration data is handled:

merge (B): Merges the new configuration with the existing one.

replace: Replaces the existing configuration with the new one.

create (C): Creates a new configuration node, but will fail if the node already exists.

delete: Deletes an existing configuration node.

remove (A): Removes an existing node, but if the node does not exist, it will not generate an error.

The attribute " update " (D) is not a valid NETCONF operation attribute.

D is the correct answer as it does not exist within the NETCONF operation attribute set.

Huawei SD-WAN establishes secure tunnels between SD-WAN edge devices (CPEs, AR routers, and controllers) using tunneling protocols.

✅ B. GRE over IPsec (Correct Answer)

GRE (Generic Routing Encapsulation) over IPsec is the primary tunneling method used in Huawei SD-WAN.

GRE provides multi-protocol encapsulation, while IPsec ensures encryption and security.

Used for secure communication over public WAN links (e.g., the internet, LTE, MPLS, etc.).