In IPsec, a symmetric encryption algorithm (e.g., AES) is used for encrypting data due to its speed. To securely exchange the symmetric key between peers, asymmetric encryption algorithms (like RSA) are used.

This method ensures:

High performance (due to fast symmetric encryption)

Secure key exchange (asymmetric protection)

Exact Extract - Huawei HCIE-Datacom Guide – IPsec Encryption:

“IPsec uses symmetric algorithms to encrypt data for performance and asymmetric algorithms to securely exchange symmetric keys during IKE negotiation.”

Comprehensive and Detailed Explanation:

IP Source Guard (IPSG) is a Layer 3 security feature used to protect against IP address spoofing by filtering packets based on bound IP-MAC mappings.

Correct Statements:✔ IPSG is a Layer 3 filtering mechanism that checks if the source IP address of a packet matches the learned or configured bindings (Option B).✔ IPSG prevents unauthorized IP address changes by enforcing binding rules (Option C).✔ IPSG defends against IP spoofing attacks by dropping packets from unauthorized sources (Option D).

Incorrect Statement:❌ Option A is incorrect because IPSG does not send alarms to an NMS when an invalid packet is detected. Instead, it drops the packet.

Thus, the correct answer is A.

???? Reference: Huawei HCIE Datacom Security Guide - IP Source Guard (IPSG)

Comprehensive and Detailed In-Depth Explanation:

In the CloudCampus public cloud scenario, when devices are deployed through the Huawei registration query center, there is no need to configure DHCP Option 148 on the campus network’s DHCP server.

The registration query center automatically provides the controller IP address to the devices during the registration process.

DHCP Option 148 is typically used to provide the iMaster NCE-Campus address in on-premises or private cloud scenarios.

In the public cloud scenario, the devices obtain this information directly from the Huawei cloud platform, making Option 148 unnecessary.

Comprehensive and Detailed Explanation:

Ethernet VPN (EVPN) is an advanced L2VPN technology that enhances MAC learning and forwarding in data center and enterprise networks. Different EVPN route types are used for various functions:

Ethernet A-D (Auto-Discovery) Route: Used for auto-discovery of PE devices and does carry labels.

MAC/IP Advertisement Route: Distributes MAC-to-IP mappings and carries labels for forwarding decisions.

Ethernet Segment Route: Does not carry MPLS labels as it is used to signal multi-homing and redundancy information.

Inclusive Multicast Route: Used for multicast forwarding and carries labels for tunnel identification.

Since Ethernet Segment Route is used only for multi-homing signaling and does not carry MPLS labels, the correct answer is C.

???? Reference: Huawei HCIE Datacom Study Guide - EVPN Route Types

Understanding User Authentication Points in a Network

Authentication points can be deployed at different network layers based on security and scalability needs:

✅ Access Layer Authentication:

Ensures high security & granular control (user-level authentication).

Preferred in high-security enterprise networks.

✅ Aggregation or Core Layer Authentication:

Reduces authentication overhead but provides less granular control.

Suitable for large-scale networks where authentication load needs to be balanced.

Analysis of the Answer Choices:

✅ A. Deploying user authentication points at the access layer achieves granular permission management and high network security.

Correct: Provides fine-grained control per user and prevents unauthorized access.

✅ B. Moving user authentication points from the access layer to the aggregation or core layer greatly reduces the number of user authentication points, thereby effectively mitigating the pressure on the AAA server.

Correct: Fewer authentication points mean less load on the AAA server.

✅ C. Deploying user authentication points at the access layer has both advantages and disadvantages when compared to doing so at the aggregation or core layer. Policy association can be applied if user authentication points are deployed at the access layer.

Correct: Policy-based authentication is best applied at the access layer for granular control.

❌ D. When user authentication points are moved from the access layer to the aggregation layer, MAC address authentication for users may fail.

Incorrect: MAC authentication works at both layers, but policy adjustments may be needed.

✅ Reference: Huawei HCIE-Datacom Guide – User Authentication Strategies in Enterprise Networks

PQ (Priority Queuing) ensures low-latency services like voice and video are prioritized.

WFQ (Weighted Fair Queuing) fairly allocates remaining bandwidth to services like FTP.

Option B provides a balanced approach: guarantees for voice/video via PQ, and fairness for FTP via WFQ.

Exact Extract - Huawei HCIE-Datacom QoS Module:

“Voice and video traffic should be handled by PQ to minimize delay and jitter. Non-critical services such as FTP should be placed in WFQ queues to ensure bandwidth fairness.”

Comprehensive and Detailed In-Depth Explanation:

The Huawei SD-WAN Solution uses HTTP/2 as the primary protocol to report device performance data to the controller.

HTTP/2 is chosen for its high efficiency, low latency, and enhanced data transfer speed.

It supports bidirectional communication between devices and the iMaster NCE-Campus controller.

While protocols like NetFlow and SNMP are traditionally used for monitoring, Huawei SD-WAN specifically uses HTTP/2 for real-time performance reporting and control due to its modern web-based architecture.

In SRv6 (Segment Routing over IPv6), flavors are extensions to standard SRv6 instructions that define how the Segment Routing Header (SRH) is handled at specific points:

PSP (Penultimate Segment Pop): Instructs the penultimate node to remove the SRH before reaching the last node → ✅

USD (Ultimate Segment Decapsulation): Instructs the final segment to remove the SRH and IPv6 header, exposing the payload → ✅

PSD (Penultimate Segment Decapsulation): Instructs the penultimate node to remove the SRH and deliver the payload → ✅

USP (Ultimate Segment Pop) is not a standard flavor in Huawei SRv6 implementations → ❌

Correct answers: A, B, D

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.).