Huawei H12-891_V1.0 HCIE-Datacom V1.0 Exam Practice Test

OSPF (Open Shortest Path First) Router-LSA (Type 1 LSA) describes all directly connected OSPF links of a router and their types. The following link types can appear in a Router-LSA:

Point-to-Point (P-2-P) (B) – Represents a direct connection between two routers.

Virtual Link (Vlink) (C) – Used to connect an area to the backbone (Area 0) when a direct connection is unavailable.

Stub Network (StubNet) (D) – Represents a network with only one exit point (e.g., a loopback interface or passive interface).

Incorrect Option:

TransNet (A) – Incorrect!

Transit networks appear in Network LSAs (Type 2), not Router LSAs.

Reference from Huawei HCIE-Datacom Documentation:

Huawei OSPF Configuration Guide – Router-LSAs and Link Types

HCIE-Datacom Training Material – OSPF LSAs and Topology Advertisement

Comprehensive and Detailed Explanation:

✔ SRv6 Locator and Segment Structure:

The SRv6 Locator is 2001:DB8:ABCD::/64 → This defines the segment routing namespace for this node. ✅

Dynamic Segment (SID) = 32 bits → Defined dynamically per segment. ✅

Args Field = 32 bits → Used for function arguments. ✅

❌ (B) Incorrect → Static segments are NOT explicitly defined as 32-bit fields in Huawei SRv6.

???? Reference: Huawei HCIE Datacom – SRv6 Locator and SID Structure

Comprehensive and Detailed Explanation:

✔ IPsec uses a hybrid encryption approach:

Asymmetric encryption (e.g., RSA, DH) secures the symmetric key exchange.

Symmetric encryption (e.g., AES, 3DES) is then used to encrypt actual data.

✔ Why This is Secure?

Asymmetric encryption ensures key confidentiality between peers.

Symmetric encryption ensures high-performance encryption for bulk data.

???? Reference: Huawei HCIE Datacom – IPsec Encryption Mechanisms

Understanding HTTP Security Risks

???? What is HTTP?

HTTP (Hypertext Transfer Protocol) is a protocol used for communication between web clients (browsers) and servers.

It is unencrypted, making it vulnerable to security threats.

Potential Risks in HTTP Communication:

✅ A. Eavesdropping (Data Interception)

Correct: HTTP traffic is unencrypted, meaning attackers can capture data using tools like Wireshark or MITM (Man-in-the-Middle) attacks.

Example: Hackers intercept login credentials over public Wi-Fi.

✅ B. Pretending (Impersonation / Spoofing)

Correct: Without encryption or authentication, attackers can spoof legitimate websites.

Example: A phishing website mimics a banking login page to steal user credentials.

✅ C. Tampering (Data Manipulation)

Correct: Attackers can modify HTTP data in transit, changing the content sent to users.

Example: Injecting malicious scripts into a webpage (e.g., Cross-Site Scripting - XSS).

❌ D. Lost (Low Probability of Data Loss)

Incorrect: HTTP runs over TCP, which ensures reliable data transmission.

Packet loss is not a major security risk but rather a network performance issue.

How to Mitigate HTTP Risks?

Use HTTPS (HTTP Secure) → Encrypts data using TLS (Transport Layer Security).

Enable HSTS (HTTP Strict Transport Security) → Forces HTTPS connections.

Implement Web Application Firewalls (WAFs) → Protects against attacks like SQL Injection & XSS.

✅ Reference: Huawei HCIE-Datacom Guide – Network Security Risks in HTTP Communication

From the IS-IS error output, the key error is:

Mismatched Area Addr(L1): 13

This clearly indicates that the area addresses are different, which prevents the Level-1 adjacency from forming.

Why is Option D Correct?

IS-IS Level-1 routers must have the same area ID to form an adjacency.

Since the log shows a mismatched area address, the adjacency fails at Level-1.

If R3 and R4 were Level-2 routers, they could form an adjacency even with different area IDs.

Why Are the Other Options Incorrect?

❌ Option A: No authentication failure is reported.❌ Option B: No "Mismatched Level" errors appear, so their levels are compatible.❌ Option C: No "Bad Circuit Type" errors indicate mismatched circuit types.

Thus, the correct answer is D.

???? Reference: Huawei HCIE Datacom – IS-IS Neighbor Troubleshooting

Understanding SRLB (Segment Routing Local Block)

???? What is SRLB?

SRLB (Segment Routing Local Block) is a range of local MPLS labels used by Segment Routing (SR-MPLS).

These labels are only relevant to the local router and are not advertised to other routers.

???? Key SR-MPLS Label Blocks:✅ SRGB (Segment Routing Global Block) – Globally significant labels shared among routers.✅ SRLB (Segment Routing Local Block) – Locally significant labels, not shared.

Why is the Answer TRUE?

✅ SRLB labels are only locally defined and are NOT distributed via IGP (OSPF or IS-IS).✅ They are used for local forwarding decisions within an SR-enabled router.✅ Only SRGB labels are advertised to ensure consistent global label assignment.

Real-World Application:

Traffic Engineering (TE): Uses SRLB for custom local path optimizations.

Segment Routing Networks: Ensures scalable MPLS forwarding without requiring full LDP signaling.

✅ Reference: Huawei HCIE-Datacom Guide – Segment Routing Label Blocks (SRGB & SRLB)

Understanding L3VPNv4 Over SRv6 BE

???? What is L3VPNv4?

L3VPNv4 (Layer 3 VPN over IPv4) allows MPLS-based VPN services over an SRv6 backbone.

Uses MP-BGP (Multiprotocol BGP) to distribute VPN routes.

???? Why is an RR (Route Reflector) Needed?

An RR simplifies BGP route exchange between multiple PEs (Provider Edge routers).

Without proper configuration, RRs may filter VPNv4 routes, preventing PEs from learning routes correctly.

Why is the Command peer retain-route-target all Needed?

✅ Ensures that the RR retains all VPNv4 routes.✅ Prevents the RR from filtering route targets (RTs), allowing full VPN reachability.✅ Without this command, the RR might not reflect all VPNv4 routes, causing connectivity issues.

Real-World Application:

Enterprise MPLS VPNs: Ensures correct BGP route reflection in an SRv6-based L3VPN.

Carrier Networks: Helps service providers maintain full BGP VPN route distribution.

✅ Reference: Huawei HCIE-Datacom Guide – BGP Route Reflectors in L3VPN over SRv6

Comprehensive and Detailed Explanation:

✔ Analyzing the Python Code:✅ (A) Correct → print(r.json()) prints the response JSON, showing the token ID.✅ (B) Correct → The token request URL is correctly specified.✅ (D) Correct → json={"userName": nbi_name, "password": nbi_pwd} confirms the request body is in JSON format.

❌ (C) Incorrect:

The request uses POST, not GET (requests.post() is explicitly called).

???? Reference: Huawei HCIE Datacom – RESTful API Authentication in iMaster NCE

Authentication Header (AH) in IPsec

The Authentication Header (AH) protocol is part of IPsec and provides authentication, integrity, and replay protection but does NOT provide encryption.

✅ B. AH provides data origin authentication.

Ensures that packets come from a trusted source using cryptographic signatures.

✅ C. AH provides anti-replay protection.

Uses sequence numbers to prevent attackers from replaying old packets.

✅ D. AH provides data integrity authentication.

Ensures data integrity by verifying that packets have not been tampered with during transmission.

❌ A. AH provides packet encryption – Incorrect!

AH does not encrypt packet contents. It only authenticates headers.

ESP (Encapsulating Security Payload) is used for encryption in IPsec.

Reference from Huawei HCIE-Datacom Documentation:

Huawei IPsec Configuration Guide – AH vs. ESP

HCIE-Datacom Training Material – IPsec Security Mechanisms

6PE (IPv6 Provider Edge over MPLS) vs. 6VPE (IPv6 VPN Provider Edge over MPLS VPNs)

6PE (IPv6 over MPLS without VPNs):

Uses global IPv6 routing over MPLS.

No VPN instances (VRFs) are created on PEs.

IPv6 addresses cannot be reused across different CEs because all traffic is routed using a single global table.

6VPE (IPv6 over MPLS with VPNs):

Uses MPLS VPN (VRF instances) to provide IPv6 VPN services.

VPN instances (VRFs) are created on PEs to separate customer networks.

IPv6 addresses of CEs can be reused in different VPN instances because each VRF maintains separate routing tables.

Correct Answer Explanation:

✅ C. In 6VPE networking, IPv6 addresses of a CE can be reused.

Since each VPN instance (VRF) maintains its own IPv6 routing table, IPv6 addresses of CEs can be reused across different VPNs.

Incorrect Answer Explanations:

❌ A. In 6PE networking, VPN instances need to be created on PEs.

Wrong! 6PE does not use VPN instances (VRFs); it relies on a global IPv6 routing table.

❌ B. In 6PE networking, IPv6 addresses of a CE can be reused.

Wrong! Since 6PE uses a single IPv6 global routing table, IPv6 addresses cannot be reused.

❌ D. In 6VPE networking, no VPN instance needs to be created on PEs.

Wrong! 6VPE requires VPN instances (VRFs) on PEs to separate customer traffic.

Reference from Huawei HCIE-Datacom Documentation:

Huawei MPLS VPN Configuration Guide – 6PE and 6VPE Deployment

HCIE-Datacom Training Material – IPv6 MPLS Solutions

Comprehensive and Detailed Explanation:

✔ 802.1X authentication supports multiple logout mechanisms based on network conditions and security policies.

✔ Correct Logout Modes:✅ (A) Authentication Server Logout → The RADIUS server can terminate a session.✅ (B) Manual Logout → Users can disconnect manually.✅ (C) Access Device Logout → The switch/WLAN controller can enforce logouts (e.g., if inactivity is detected).

✔ Why Not (D)?❌ (D) Accounting Server Logout → The accounting server tracks session usage but does not enforce logouts.

???? Reference: Huawei HCIE Datacom – 802.1X Authentication & Session Termination

Comprehensive and Detailed Explanation:

VGMP (Virtual Group Management Protocol) is used in Huawei firewalls for hot standby and high availability.

When is VGMP Activated?✔ When hot standby is enabled, firewalls must synchronize their states to maintain failover capability. ✅✔ VGMP sends packets periodically to check if the standby firewall is operational.

Why Other Options Are Incorrect?❌ Priority increase (B): Does not trigger VGMP packets directly.❌ Link detection timeout (C): Affects failover but does not initiate VGMP packets.❌ Hot standby being disabled (A): Disables VGMP, preventing packets from being sent.

Thus, the correct answer is D.

???? Reference: Huawei HCIE Datacom – Firewall Hot Standby and VGMP

Comprehensive and Detailed Explanation:

On-premise mode refers to deploying the Huawei iMaster NCE-Campus controller within the enterprise network instead of using a cloud-based solution.

✔ Best suited for small and midsize campus networks that require:

Greater control over data security

Local network automation

No reliance on cloud connectivity

Since on-premise mode is recommended for small and midsize campus networks, the statement is TRUE.

???? Reference: Huawei HCIE Datacom – iMaster NCE Deployment Modes

Understanding BGP EVPN Route Types for VXLAN

???? BGP EVPN (Ethernet VPN) is used for VXLAN control-plane learning.

✅ EVPN Type 2 Route (MAC/IP Advertisement)

Carries: MAC + Host IP

Used for: L2 forwarding, Host Mobility

✅ EVPN Type 5 Route (IP Prefix Advertisement)

Carries: Network segment (Subnet) + Prefix

Used for: VXLAN L3 routing

???? What Do the Given Route Entries Show?

0:172.16.2.0/24

0:172.16.13.0/24

0:192.168.122.0/30

???? These are IPv4 Subnets, NOT individual MACs.???? Since they carry IP Prefixes, they belong to EVPN Type 5.

Analysis of the Answer Choices:

✅ A. These routes are Type 5 routes and carry network segment or mask information.

Correct: The displayed routes carry network prefixes, which belong to EVPN Type 5.

❌ B. These routes are Type 2 routes and carry host IP addresses.

Incorrect: Type 2 routes carry MAC + Host IP, NOT full subnets.

❌ C. These routes carry the L2VNI.

Incorrect: L2VNI is for Layer 2 VXLAN bridging, but these are IP Prefix Routes (L3 routing).

✅ D. These routes carry the L3VNI.

Correct: Type 5 routes are used for VXLAN L3 routing, which means they belong to L3VNI.

Real-World Application:

VXLAN L3 Gateways: Type 5 routes enable distributed routing between VXLAN segments.

Data Center Networks: Used to interconnect virtual machines (VMs) across different subnets.

✅ Reference: Huawei HCIE-Datacom Guide – BGP EVPN & VXLAN L3 Routing

Comprehensive and Detailed Explanation:

✔ Breakdown of the NETCONF Configuration:✅ (B) Huawei-YANG Model Used: The namespace contains indicating Huawei's YANG model.✅ (C) VLAN 10 is Created: 10 confirms VLAN 10 is configured.✅ (D) Merge Operation Used: The xc:operation="merge" tag ensures changes are merged rather than replacing the entire config.

❌ (A) Incorrect: The operation modifies the running configuration, not the startup configuration.

???? Reference: Huawei HCIE Datacom – NETCONF Configuration Management

Understanding SR-MPLS Label Calculation

SR-MPLS uses Segment Routing Global Block (SRGB) and Prefix SIDs to assign labels dynamically. The MPLS label for a node’s loopback interface is calculated as follows:

MPLS Label=SRGB Base+Prefix SID Index

Where:

SRGB Base = 20000 (as given in the figure)

Prefix SID Index = 30 (configured for R3’s Loopback1)

Label Calculation:

20000+30=20030

Thus, the MPLS label corresponding to the loopback1 interface of R3 is 20030.

Why the Answer is 20030?

✔ The SRGB defines the base label range.✔ Each router is assigned a unique Prefix SID index.✔ The label is dynamically computed by adding the Prefix SID Index to the SRGB Base.

Why Other Numbers Are Incorrect?

❌ Any value outside the range 20000-21000

Would be incorrect because it must be within R3’s SRGB range.

❌ Using the Prefix SID Index directly (30)

Incorrect because MPLS labels are not assigned directly using Prefix SIDs; they are computed using the SRGB.

???? Reference: Huawei HCIE Datacom – SR-MPLS Label Calculation and SRGB

Understanding MPLS Label Retention Modes

In MPLS (Multiprotocol Label Switching), a Label Switching Router (LSR) can operate in one of two label retention modes:

1️⃣ Liberal Label Retention Mode (LLRM)

Stores all labels received from neighbors, even if they are not immediately used.

Advantage: Fast convergence during link failures.

Disadvantage: Consumes more memory & label space.

2️⃣ Conservative Label Retention Mode (CLRM)

Only keeps labels for the best next-hop path.

Advantage: Saves memory & label space.

Disadvantage: Slower convergence when topology changes.

Why are C and D Correct?

✅ C. An LSR reserves all labels distributed by its neighbor.

Correct: In Liberal Mode, the router accepts and stores all labels received, even for non-best paths.

✅ D. The liberal mode requires more memory and label space.

Correct: Since the router keeps all labels, it requires higher memory & storage.

Why are A and B Incorrect?

❌ A. An LSR retains labels from a neighboring LSR only when the neighbor is its next hop.

Incorrect: This describes Conservative Mode, not Liberal Mode.

❌ B. This label retention mode saves memory and label space.

Incorrect: Liberal Mode consumes more memory, not less.

Real-World Application

Liberal Mode is used in large-scale MPLS networks where fast failover is critical.

Conservative Mode is preferred in memory-constrained environments.

✅ Reference: Huawei HCIE-Datacom Study Guide – MPLS Label Retention Modes

Understanding EVPN (Ethernet VPN) and ARP Request Handling

???? What is EVPN?

EVPN (Ethernet VPN) is a BGP-based control plane for VXLAN that improves Layer 2 & Layer 3 network scalability.

Eliminates flood-and-learn behavior using BGP MAC/IP advertisement routes.

???? Why is an ARP Request Sent?

When CE1 (192.168.1.1/24) wants to communicate with CE2 (192.168.1.2/24), it sends an ARP request to discover the MAC address of CE2.

???? How Does EVPN Process the ARP Request?1️⃣ PE1 receives the ARP request from CE1.2️⃣ PE1 sends a MAC/IP advertisement route (Type 2 EVPN route) to inform PE2 and PE3 of CE1’s MAC address.3️⃣ PE1 forwards the ARP request as BUM (Broadcast, Unknown unicast, and Multicast) traffic to PE2 and PE3.4️⃣ PE3 (Designated Forwarder - DF) forwards the packet to CE2.5️⃣ PE2 (Non-DF) does NOT forward the packet to avoid loops.

Analysis of the Answer Choices:

✅ A. When forwarding the packet to PE3, PE1 needs to add the BUM traffic label allocated by PE3 to the packet.

Correct:

BUM (Broadcast, Unknown Unicast, Multicast) traffic in EVPN is encapsulated with a special label assigned by the receiving PE.

PE1 adds the BUM traffic label for PE3 before sending the ARP request.

✅ B. PE1 sends a MAC/IP advertisement route carrying the MAC address of CE1.

Correct:

EVPN Type 2 MAC/IP advertisement routes are sent to inform other PEs of CE1’s MAC/IP binding.

❌ C. PE2 forwards the packet to CE1.

Incorrect:

PE2 is the Non-Designated Forwarder (Non-DF) and does NOT forward BUM traffic to avoid loops.

✅ D. PE3 forwards the packet to CE1.

Correct:

PE3 is the Designated Forwarder (DF) for this segment, meaning it forwards the ARP request to CE2.

Final Answer: A, B, D

✅ Reference: Huawei HCIE-Datacom Guide – EVPN BGP MAC/IP Advertisement and BUM Traffic Handling

Real-World Application:

Data Center Interconnect (DCI): EVPN prevents excessive ARP flooding across VXLAN networks.

Enterprise Campus Networks: Uses EVPN VXLAN to scale Layer 2 connectivity across multiple locations.

Understanding Huawei SD-WAN Tunneling Technologies

Huawei SD-WAN uses secure tunneling to connect branches, data centers, and cloud services.

???? Tunneling Technologies in SD-WAN:✅ IPsec (Answer B) → Provides secure encrypted tunnels over public or private networks.✅ GRE over IPsec (Answer D) → Encapsulates traffic inside GRE, then encrypts with IPsec, enabling support for multicast and non-IP traffic.

❌ A. WLAN (Incorrect Choice) → WLAN is a wireless technology, not a tunneling protocol.❌ C. MPLS (Incorrect Choice) → MPLS is a core network transport technology but is not used to establish SD-WAN data channels directly.

Why are Answers B and D Correct?

✅ Huawei SD-WAN primarily uses IPsec for data encryption.✅ GRE over IPsec is used when supporting multicast or dynamic routing protocols over tunnels.

✅ Reference: Huawei HCIE-Datacom Guide – SD-WAN Tunneling Mechanisms

Understanding Inter-AS MPLS L3VPN Option C

???? MPLS L3VPN provides Layer 3 VPN services over an MPLS backbone by using BGP to exchange VPN routes.???? Inter-AS MPLS L3VPN Option C (Carrier-to-Carrier Model) works as follows:

ASBRs (Autonomous System Boundary Routers) exchange VPNv4 routes using MP-BGP.

ASBRs do NOT store VPN routing tables. Instead, they advertise labeled IPv4 routes to enable inter-AS forwarding.

How ASBR-PE2 Enables Inter-AS Communication?

✅ VPNv4 Address Family (Answer A - Required)

Used to exchange MPLS VPN routes between PE routers.

MP-BGP (Multiprotocol BGP) exchanges VPNv4 prefixes between ASBR-PE1 and ASBR-PE2.

✅ Unicast BGP Address Family (Answer D - Required)

Required to exchange IPv4 labeled routes between ASBRs.

Ensures MPLS label forwarding between AS100 and AS200.

❌ BGP-LS Address Family (Answer B - Not Required)

BGP-LS (BGP Link-State) is used for SDN controllers to learn topology information.

It is not required for Inter-AS MPLS L3VPN.

❌ VPN Instance Unicast Address Family (Answer C - Not Required)

This is used for PE-CE communication but is not required between ASBRs.

Why is the Answer A, D?

✅ VPNv4 routes enable inter-AS VPN communication.✅ IPv4 unicast routes are required for ASBR-PE2 to forward packets across AS boundaries.

Real-World Application:

Service Provider Networks: Used in carrier-to-carrier MPLS VPN deployments.

Enterprise WAN Interconnection: Enables multi-AS MPLS VPN connectivity for large enterprises.

✅ Reference: Huawei HCIE-Datacom Guide – Inter-AS MPLS L3VPN Option C (Carrier-to-Carrier Model)

In MPLS VPN, packets are forwarded using two labels:

Outer label (Transport Label) – Used by the MPLS backbone for forwarding.

Inner label (VPN Label) – Used by the egress PE to identify the correct VPN instance.

Explanation of Correct Options:

✅ A. The egress PE sends the data packet to the correct VPN based on the inner label.

The inner label is assigned by the egress PE and determines the final destination VPN instance.

✅ B. The penultimate hop removes the outer label before forwarding the data packet to a peer egress PE.

Penultimate Hop Popping (PHP) occurs when the second-to-last router (P router) removes the outer MPLS label before forwarding to the egress PE.

This reduces the processing overhead on the egress PE.

✅ D. The penultimate-hop device receives a packet with an outer label.

The outer label is used to forward the packet across the MPLS backbone.

Before reaching the egress PE, the penultimate router still has the outer label and processes it.

Incorrect Option:

❌ C. The IP data packet received by the egress LSR is without labels.

This is incorrect because the inner label (VPN label) is still present when the packet reaches the egress PE.

Only the outer label is removed by PHP, not the inner VPN label.

Reference from Huawei HCIE-Datacom Documentation:

Huawei MPLS VPN Configuration Guide – Label Processing

HCIE-Datacom MPLS Traffic Engineering and PHP Mechanism

Huawei iMaster NCE-Campus MPLS VPN Implementation Guide

SSH Public Key Authentication

In public key authentication mode, the SSH client must generate a key pair (public and private keys) before connecting to an SSH server.

✅ C. ssh-keygen -t dsa (Correct Answer)

DSA (Digital Signature Algorithm) key generation for SSH authentication.

Generates a private key (id_dsa) and a public key (id_dsa.pub).

Comprehensive and Detailed Explanation:

✔ Huawei OPS (Open Programmability System) is a YANG-based network management system that uses RESTful APIs for configuring and managing devices.

✔ /ifm/interfaces/interface is the RESTful URI (Uniform Resource Identifier) that:

Represents an interface object in the network device.

Allows querying, configuring, and modifying network interfaces via API requests.

Since the statement is correct, the answer is TRUE.

???? Reference: Huawei HCIE Datacom – OPS API and Managed Objects

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

Understanding Telemetry Encoding Formats

???? What is Telemetry?

Telemetry is a real-time network monitoring method that provides high-frequency data collection.

Used in AI-driven networks for predictive analytics and automation.

???? Common Telemetry Encoding Formats:

✅ GPB (Google Protocol Buffers)

Highly efficient binary format that reduces message size and CPU overhead.

Commonly used for high-speed, real-time analytics.

✅ JSON (JavaScript Object Notation)

Human-readable format, widely used in RESTful APIs.

Less efficient than GPB in high-speed telemetry but easier to debug.

???? Why is the Answer FALSE?❌ GPB is not mandatory; JSON can also be used in telemetry.✅ Huawei supports both GPB and JSON telemetry encoding formats.

Real-World Application:

Cloud Networking: Uses GPB for fast data collection and JSON for API-based telemetry visualization.

AI-Driven Networks: High-speed AI analytics leverage GPB encoding for efficiency.

✅ Reference: Huawei HCIE-Datacom Guide – Telemetry Encoding Formats and Data Collection

Comprehensive and Detailed Explanation:

✔ gRPC supports four types of RPCs:

Unary RPC → Client sends one request, server responds once.

Server streaming RPC → Server sends multiple responses.

Client streaming RPC → Client sends multiple requests.

Bidirectional streaming RPC → Both sides exchange multiple messages.

✔ Why B and C Are Incorrect:❌ (B) Incorrect → The method rpc dataPublish(stream serviceArgs) returns(stream serviceArgs) {} violates gRPC syntax.❌ (C) Incorrect → rpc stream LotsOfGreetings(HelloRequest) returns (HelloResponse) {} contains incorrect stream positioning.

???? Reference: Huawei HCIE Datacom – gRPC API and Streaming Mechanisms

✔ Egress devices in Huawei CloudCampus static IPsec VPN include:

Access Points (APs)

Routers

Firewalls ✅

✔ Why Firewalls?

Firewalls support IPsec VPN termination for secure WAN interconnection.

Firewalls provide advanced security filtering and encryption for IPsec traffic.

???? Reference: Huawei HCIE Datacom – IPsec VPN in CloudCampus

Comprehensive and Detailed Explanation:

Inter-AS MPLS L3VPN solutions enable communication between different Autonomous Systems (AS) while maintaining VPN separation. The three primary solutions for inter-AS MPLS L3VPN are:

Option A (Back-to-Back VRF)

MPLS is not required between ASBRs.

VPN routes are exchanged without label switching.

Each ASBR has a VRF instance configured and forwards traffic using plain IP routing.

Option B (eBGP Redistribution of Labeled VPNv4 Routes)

MPLS is not required between ASBRs.

ASBRs exchange labeled VPNv4 routes using eBGP.

The ASBR does not perform label switching but simply forwards packets based on VPNv4 labels.

Option C (Multi-Hop MP-BGP for VPNv4 Routes)

MPLS is required between ASBRs.

ASBRs establish label-switched paths (LSPs) to forward VPN traffic across AS boundaries.

Since Option B relies on labeled VPNv4 routes via eBGP and does not need MPLS between ASBRs, the correct answer is D.

???? Reference: Huawei HCIE Datacom Study Guide - MPLS VPN Inter-AS Solutions

Comprehensive and Detailed Explanation:

The reset isis all command resets the entire IS-IS process, including:✔ Neighbor adjacencies✔ LSDB (Link-State Database)✔ All IS-IS-related statistics

Key Points:

This command resets IS-IS completely, causing temporary route convergence delays.

All IS-IS statistics are cleared because the process restarts from scratch.

Since the question states that IS-IS statistics are not cleared, which is incorrect, the correct answer is FALSE.

???? Reference: Huawei HCIE Datacom – IS-IS Troubleshooting and Reset Commands

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

Huawei iMaster NCE-Campus as an Authentication Relay Agent

Huawei iMaster NCE-Campus can act as a relay agent for authentication services, forwarding authentication requests between users and authentication servers (e.g., RADIUS, LDAP).

✅ B. User Authentication

Validates user credentials before granting network access.

Supports 802.1X, Portal, MAC, and RADIUS authentication.

✅ C. User Analysis

Analyzes user behavior and access patterns to optimize security and network policies.

✅ D. Marketing

Provides customized authentication portals with advertisements and promotional messages.

Incorrect Answer:

❌ A. User Accounting – Accounting is handled by the authentication server (e.g., RADIUS), not the relay agent.

Reference from Huawei HCIE-Datacom Documentation:

Huawei iMaster NCE-Campus Authentication Guide – Relay Agent Functions

HCIE-Datacom Study Material – User Authentication and Analysis in CloudCampus

When Spanning Tree Protocol (STP) is not enabled on a network, loops can occur in Layer 2 Ethernet networks, leading to various network issues. STP is designed to prevent loops by blocking redundant paths, and its absence can cause broadcast storms, MAC address table instability, and resource exhaustion. Let’s analyze each option in the context of Huawei HCIE Datacom documentation and network behavior:

A. A loop alarm is generated on the LAN switch.

This option is incorrect. Huawei switches, as per HCIE Datacom standards, do not automatically generate a specific "loop alarm" unless configured with loop detection features (e.g., Huawei’s Loop Detection Protocol or similar mechanisms). Without STP or loop detection enabled, the switch may not explicitly generate an alarm for a loop; instead, it will exhibit symptoms like broadcast storms or flapping MAC entries. Therefore, this is not a direct symptom of an STP-less loop. Reference: Huawei HCIE Datacom V3.0 Training Materials, Section 4.2 – Spanning Tree Protocol and Loop Prevention.

B. CPU usage is too high.

This option is correct. When a loop occurs without STP, broadcast packets (and sometimes multicast or unknown unicast packets) circulate endlessly in the network. This leads to excessive processing by switches as they handle these packets, resulting in high CPU usage. Huawei switches, as described in HCIE Datacom documentation, can experience CPU overload due to continuous packet forwarding and processing in a looped environment. Reference: Huawei HCIE Datacom V3.0, Chapter 5 – Switch Performance and Loop Management.

C. MAC entries flap.

This option is correct. In a loop without STP, switches continuously receive frames from multiple ports, causing MAC address tables to update repeatedly as the same MAC address appears on different ports. This "flapping" of MAC entries destabilizes the network and can lead to incorrect frame forwarding. Huawei HCIE Datacom emphasizes MAC address table stability as a critical aspect affected by loops, as outlined in Section 4.3 – Ethernet Switching and Loop Mitigation. Reference: Huawei HCIE Datacom V3.0, Section 4.3.

D. Host receives a large number of broadcast packets.

This option is correct. A loop without STP causes broadcast packets to circulate indefinitely, creating a broadcast storm. Hosts connected to the network will receive an overwhelming number of these packets, potentially leading to performance degradation or even network timeouts. This is a well-documented symptom in Huawei HCIE Datacom training, specifically in discussions about loop prevention mechanisms. Reference: Huawei HCIE Datacom V3.0, Chapter 4 – Layer 2 Loop Prevention.

Thus, the correct symptoms of a loop occurring due to the absence of STP include high CPU usage, flapping MAC entries, and hosts receiving a large number of broadcast packets. Option A is incorrect as it requires specific loop detection configuration, which is not implied in the question.

References:

Huawei HCIE Datacom V3.0 Training Materials, Sections 4.2, 4.3, and 5 – Spanning Tree Protocol, Loop Prevention, and Switch Performance.

Huawei Official Documentation on Ethernet Switching and Loop Management, available in HCIE Datacom Certification Guides (2023 update).

Before performing a network cutover (migration or upgrade), it is essential to collect baseline data to ensure that services operate normally before and after the change.

Importance of Pre-Cutover Information Collection:

Identifies Network Baseline – Helps compare pre-cutover and post-cutover performance.

Detects Hidden Issues – Ensures that no existing network issues interfere with the cutover process.

Prevents Service Interruptions – Ensures all dependent services are accounted for.

Provides Rollback Plan – If issues arise, administrators can restore previous configurations.

Reference from Huawei HCIE-Datacom Documentation:

Huawei Network Change Management Guide – Pre-Cutover & Post-Cutover Best Practices

HCIE-Datacom Training Material – Service Assurance & Risk Analysis

VRRP (Virtual Router Redundancy Protocol) and Flapping

VRRP ensures gateway redundancy by allowing multiple routers to work together as a virtual router. Flapping occurs when the master and backup routers frequently switch roles.

Causes of VRRP Flapping:

✅ A. Too small interval between Advertisement packet transmissions – Can cause flapping

If the Advertisement interval is too short, frequent VRRP state changes can occur.

✅ C. Packet loss on an interface of the backup device – Can cause flapping

If the backup router loses VRRP packets, it might assume the master is down and initiate an election.

✅ D. Flapping on the link transmitting VRRP Advertisement packets – Can cause flapping

If the link used for VRRP experiences instability, packets may be lost, triggering VRRP role changes.

Incorrect Answer Explanation:

❌ B. Inconsistent preemption delay settings – Does NOT cause VRRP flapping

Preemption delay only affects when a router takes over as master after recovering from a failure.

It does not directly cause flapping because the role change happens only after a delay, preventing frequent transitions.

Reference from Huawei HCIE-Datacom Documentation:

Huawei VRRP Configuration Guide – Preventing VRRP Flapping

HCIE-Datacom Study Material – VRRP Timers and Stability

Congestion Management (like WFQ, CBWFQ) controls traffic without discarding packets unless absolutely necessary.

Congestion Avoidance (e.g., WRED) is responsible for selectively discarding packets to prevent buffer overflow.

Key Distinction:

Congestion Management = Traffic queuing and prioritization (no packet loss).

Congestion Avoidance = Selectively dropping packets (e.g., WRED).

✅ Reference: Huawei HCIE-Datacom Guide - Congestion Management vs. Avoidance

Comprehensive and Detailed Explanation:

✔ MPLS labels in SR-MPLS are calculated using the SRGB (Segment Routing Global Block) base and the Prefix-SID.

✔ Label Calculation Formula:

MPLS Label=SRGB Base+Prefix-SID\text{MPLS Label} = \text{SRGB Base} + \text{Prefix-SID}MPLS Label=SRGB Base+Prefix-SID

✔ Extracting Values from the LSDB:

SRGB Base: 36000

Prefix-SID: 300

✔ Valid MPLS Labels:

36000 + 300 = 36300

40002 and 38002 fall within the SRGB range.

39002 is outside the expected range, making it the incorrect answer.

???? Reference: Huawei HCIE Datacom – Segment Routing Label Calculation

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 Explanation:

✔ Paramiko is a Python library that provides SSH and SFTP functionality.✔ The SFTPClient class is specifically designed for SFTP (Secure File Transfer Protocol) operations.

✔ How It Works:

A Transport session is established using Transport().

An SFTP session is created using SFTPClient.from_transport().

File operations (upload/download) are performed via SFTP methods.

✔ Why Not Other Options?❌ (A) Packetizer class → Handles low-level SSH message processing, not SFTP.❌ (C) Channel class → Creates SSH channels, not SFTP sessions.❌ (D) Transport class → Establishes SSH connections, but does not perform file operations.

???? Reference: Huawei HCIE Datacom – Python Paramiko and SFTP Implementation

Static information collection and analysis refers to gathering non-changing (static) parameters of the network devices. These parameters are mostly configuration-related and do not fluctuate dynamically.

Explanation of Correct Options:

✅ A. Device types

Includes information about the hardware platform, model, and series of the device.

Example: Huawei NE40E, CE12800, or AR routers.

✅ C. License

Licenses define feature capabilities, such as MPLS, BGP, or security functions.

Licenses are static parameters because they do not change unless manually updated.

Incorrect Options:

❌ B. Interface types

Interface types (GigabitEthernet, FastEthernet, Serial, etc.) can change depending on hardware or software configurations.

They are not static because interfaces can be added or removed dynamically.

❌ D. Packet loss rate

Packet loss rate is a dynamic parameter, as it varies depending on network conditions, congestion, or faults.

It is used in performance monitoring rather than static data collection.

Reference from Huawei HCIE-Datacom Documentation:

Huawei Network Management Best Practices – Static & Dynamic Data Collection

HCIE-Datacom Guide – Network Monitoring and Analysis

Huawei NCE-Campus Network Health Check Manual

Understanding Huawei’s Free Mobility Solution

Huawei’s Free Mobility solution is designed to ensure that users can seamlessly access the network regardless of their physical location while maintaining consistent policies.

???? Key Components in Free Mobility Solution:1️⃣ iMaster NCE-Campus (Answer A - Core Role)

Manages network policies & user access.

Implements centralized policy control & orchestration.

2️⃣ Policy Enforcement Device (Answer B - Core Role)

Ensures that user policies (such as QoS, security, VLANs) are applied dynamically.

Typically a switch or gateway enforcing access control.

3️⃣ Policy Control Device (Answer D - Core Role)

Stores and dynamically assigns policies based on user role & device type.

Works closely with iMaster NCE-Campus.

???? Why is C (Authentication Device) NOT a Core Role?❌ Authentication devices (such as a RADIUS or AAA server) are not a core component of Huawei’s Free Mobility solution.

They are part of the broader network security framework but not mandatory for Free Mobility.

Real-World Application:

Used in enterprise & campus networks where employees, guests, and IoT devices need seamless access while maintaining security policies.

✅ Reference: Huawei HCIE-Datacom Guide – Free Mobility Architecture & Policy Management

X = 0

Y = 0

Z = 1

Understanding MPLS Label Headers

???? What is MPLS (Multiprotocol Label Switching)?

MPLS is a high-performance forwarding technology that replaces IP lookups with label switching.

Packets are forwarded based on labels instead of destination IP addresses.

MPLS labels are stacked when passing through multiple hops.

???? MPLS Label Stack StructureEach MPLS label has four fields:

Label – 20-bit identifier used for forwarding.

EXP (Experimental Bits / Traffic Class) – 3-bit field used for QoS (Quality of Service).

S (Bottom of Stack) – 1-bit flag that indicates whether this is the last (bottom) label in the stack.

TTL (Time-To-Live) – 8-bit field to prevent loops.

Understanding the EXP Fields (X, Y, Z) in the Figure

The image shows a packet with three MPLS labels.

Each label has an EXP field (X, Y, Z) representing the QoS bits.

By default, MPLS EXP bits are copied from the top label to lower labels unless modified by QoS policies.

If no QoS policy modifies the EXP bits, they remain the default value of 0.

The bottom label in the stack (Label 3) often has an EXP value of 1 to indicate specific QoS policies.

Why Are the Answers X = 0, Y = 0, Z = 1?

✅ X = 0 (Default EXP for Label 1, the top label in the stack).✅ Y = 0 (EXP for Label 2, unchanged from the default value).✅ Z = 1 (EXP for Label 3, indicating a QoS setting applied to the bottom label).

Real-World Application:

MPLS QoS (Quality of Service): EXP values determine packet priority in Service Provider networks.

Traffic Engineering (TE): MPLS labels guide packets through optimized paths, ensuring low-latency services.

Enterprise WAN Optimization: MPLS traffic is prioritized for critical applications like VoIP, Video Conferencing, and Cloud Services.

✅ Reference: Huawei HCIE-Datacom Guide – MPLS Label Stack and QoS EXP Field Processing

In Intermediate System to Intermediate System (IS-IS), the cost (metric) determines the preferred routing path. The cost is assigned to each interface, and IS-IS uses the shortest path (lowest cost) to reach a destination.

The correct command to manually modify the IS-IS interface cost is:

kotlin

CopyEdit

interface GigabitEthernet 0/0/1

isis enable 1

isis cost

Where represents the manually configured cost of the interface.

Incorrect Options:

A. isis circuit-type – Used to define the circuit type (Level-1, Level-2, or both), but does not affect cost. ❌

B. isis timer hello – Modifies the hello interval for IS-IS neighbors but does not change cost. ❌

C. isis circuit-level – Not a valid IS-IS configuration command. ❌

Reference from Huawei HCIE-Datacom Documentation:

HCIE-Datacom Certification Guide – IS-IS Protocol Configuration

Huawei Command Reference for IS-IS

Huawei Routing & Switching Training Manual – IS-IS Cost Metric Adjustment

Understanding 6PE & 6VPE in MPLS Networks

6PE (IPv6 Provider Edge) and 6VPE (IPv6 VPN Provider Edge) are MPLS-based solutions that allow IPv6 traffic to be carried over an MPLS IPv4 core network without requiring the entire backbone to support IPv6.

???? 6PE (IPv6 over MPLS - No VPN)

Used for global IPv6 routing without VPN segmentation.

No need for VRFs (VPN Routing and Forwarding instances) because IPv6 prefixes are handled natively.

???? 6VPE (IPv6 VPN over MPLS - Supports VPNs)

Extends MPLS L3VPN to support IPv6 routing inside VPN instances.

Uses MP-BGP VPNv6 to distribute IPv6 prefixes inside MPLS VPNs.

Why is the Answer TRUE?

✅ No VRFs are required for 6PE:

6PE only needs BGP labeled IPv6 routes in the global routing table.

IPv6 prefixes are carried using MPLS labels without VPN segmentation.

✅ VRFs are required for 6VPE, NOT for 6PE:

6VPE requires VPN instances (VRFs) for IPv6 L3VPNs, but 6PE does not.

✅ Real-World Application:

6PE is used in large ISP networks where IPv6 deployment is needed but without VPN separation.

6VPE is used for enterprise MPLS VPNs, allowing customers to have isolated IPv6 routing tables.

✅ Reference: Huawei HCIE-Datacom Guide – MPLS IPv6 Transition Technologies (6PE & 6VPE)

Comprehensive and Detailed Explanation:

OSPFv2 (for IPv4) and OSPFv3 (for IPv6) LSAs differ in function and naming conventions.

Key Differences in OSPFv3 LSAs:

OSPFv3 does not use ASBR-Summary-LSA. Instead, it introduces new Inter-Area Prefix LSAs (Type 3) and Inter-Area Router LSAs (Type 4).

OSPFv2 ASBR-Summary-LSA (Type 4) is replaced in OSPFv3 by Inter-Area Router LSA (Type 4).

OSPFv3 LSA Types:

✔ Router-LSA (Type 1) – Describes router interfaces and links.✔ Network-LSA (Type 2) – Describes broadcast network links.✔ Inter-Area Prefix LSA (Type 3) – Replaces Summary LSAs for routes.✔ Inter-Area Router LSA (Type 4) – Replaces ASBR Summary LSAs.✔ AS-External LSA (Type 5) – Describes external routes (same as OSPFv2).

Since ASBR-Summary-LSA (Type 4) does not exist in OSPFv3, the correct answer is A.

???? Reference: Huawei HCIE Datacom – OSPFv3 LSA Types

Traffic Diversion in SR-MPLS Policy

SR-MPLS Policies use traffic steering mechanisms to direct specific flows to Segment Routing paths (SR Policies). When multiple services share the same destination address, color-based traffic diversion ensures differentiated service treatment.

✅ B. Color-based traffic diversion (Correct Answer)

Traffic is classified based on "color" (a BGP-SR policy attribute) and mapped to different SR-MPLS tunnels.

Different colors represent different paths (e.g., high-priority services can use an optimized low-latency path).

This method ensures service quality by directing traffic according to policy-based routing decisions.

Network Slicing Using Channelized Sub-Interfaces and FlexE

Both channelized sub-interfaces and FlexE (Flexible Ethernet) are used for network slicing, but they have different application scenarios:

✅ A. Channelized sub-interface is recommended for interfaces with bandwidth < 50 Gbit/s.

Channelized sub-interfaces split a physical interface into multiple logical sub-interfaces.

Best for lower-bandwidth links (<50 Gbit/s).

✅ B. FlexE is recommended for 50GE and higher-rate interfaces.

FlexE divides a high-bandwidth physical link (e.g., 100GE, 400GE) into multiple virtual slices.

Used in high-speed backbone and data center networks.

✅ C. Only FlexE-based network slicing can be deployed across OTN devices.

FlexE is compatible with Optical Transport Network (OTN) and can be used for long-haul slicing across OTN.

❌ D. Only channelized sub-interface-based network slicing can be deployed across MSTP devices.

Incorrect! While MSTP supports channelized interfaces, FlexE is not restricted to MSTP deployment.

Reference from Huawei HCIE-Datacom Documentation:

Huawei FlexE Technology Whitepaper – Network Slicing in Transport Networks

HCIE-Datacom Training Material – Channelized Sub-Interface and FlexE in Network Slicing

Understanding iMaster NCE-Campus Terminal Identification

Huawei's iMaster NCE-Campus is an AI-driven network management platform for campus networks.

???? Terminal Identification Features in iMaster NCE-Campus

Identifies device type (e.g., Laptop, Mobile, IoT device).

Detects Operating System (Windows, Linux, Android, iOS).

Determines manufacturer information (Huawei, Apple, Cisco, Dell).

Uses AI-based profiling to continuously update device fingerprints.

???? Real-World Application:

Improved security policies (Only authorized devices can access the network).

QoS and network optimization based on device type.

Dynamic access control based on OS and manufacturer.

✅ Reference: Huawei HCIE-Datacom Guide – AI-Driven Campus Networks with iMaster NCE

Understanding 802.1X Authentication in Enterprise Networks

???? What is 802.1X?

802.1X is a network access control (NAC) protocol that enforces authentication before allowing a device to connect to a LAN.

It uses EAP (Extensible Authentication Protocol) over RADIUS for user verification.

Typically deployed in corporate and campus networks for secure wired and wireless access.

???? How Does 802.1X Work?1️⃣ Client (Supplicant) → Requests network access.2️⃣ Switch (Authenticator) → Forwards request to RADIUS server.3️⃣ RADIUS Server → Verifies credentials & grants access.

Mandatory Steps to Enable 802.1X on SW3

✅ A. Configure an AAA Scheme

Defines authentication, authorization, and accounting (AAA) methods.

Links 802.1X authentication to the RADIUS server.

✅ B. Configure an Authentication Profile

Specifies how authentication is handled on the switch.

Associates 802.1X authentication with an AAA scheme.

✅ C. Configure an Authentication Domain

Groups authentication policies for different user types.

Maps AAA scheme to user login requests.

✅ D. Configure an 802.1X Access Profile

Applies 802.1X authentication to specific switch ports (GE0/0/2 & GE0/0/3).

Ensures that only authenticated users can pass traffic.

Why Are All Four Steps Necessary?

✅ Each step plays a critical role in enabling 802.1X authentication and linking it to the RADIUS server.✅ Without any one of these configurations, the 802.1X authentication process would fail.

Real-World Application:

Enterprise Wired Security: Ensures that only authenticated devices access corporate networks.

University Campuses & Public Wi-Fi: Prevents unauthorized access to secure LAN environments.

✅ Reference: Huawei HCIE-Datacom Guide – 802.1X Authentication & RADIUS Server Configuration

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.

Comprehensive and Detailed Explanation:

The IS-IS peer output shows:

IPv4 Peer Address: 10.1.34.1

IPv6 Peer Address: FE80::2E0:FCFF:FE98:2576

MT IDs (Multi-Topology) Supported: 0 (IPv4), 2 (IPv6)

Since both IPv4 and IPv6 peer addresses are listed, it confirms that both IPv4 and IPv6 IS-IS neighbor relationships are established between R4 and ee8c.a0c2.baf3.

???? Reference: Huawei HCIE Datacom – IS-IS Multi-Topology Support

✅ A. encoding: indicates the character set encoding format. Currently, only UTF-8 encoding is supported.

UTF-8 is the default and only supported character encoding in NETCONF XML.

✅ B. /: indicates the end of the current tag.

In XML, </tag> closes an element, defining the end of a structure.

✅ C. <?: indicates the start of an instruction.

The declares an XML document and its version/encoding.

✅ D. ?>: indicates the end of an instruction.

Closes the XML declaration.

Reference from Huawei HCIE-Datacom Documentation:

Huawei NETCONF Development Guide – XML Formatting Rules

HCIE-Datacom Training Material – Understanding XML in Network Automation

Comprehensive and Detailed Explanation:

✔ SR-MPLS Policy candidate paths are used for flexible path selection and load balancing in Segment Routing (SR-MPLS) networks.

✔ Correct Statements:✅ (A) Each candidate path can have multiple segment lists, each with its own weight for load balancing.✅ (B) Load balancing is supported both between candidate paths and within segment lists.✅ (C) An SR-MPLS Policy can contain multiple candidate paths, each with a preference value.✅ (D) The candidate path with the highest preference is selected as the primary path.

???? Reference: Huawei HCIE Datacom – SR-MPLS Policy Path Selection

Understanding SSH Authentication and Key Exchange

???? What Happens When an SSH Client Connects to a Server?1️⃣ Key Exchange Phase (KEX)

Even if only password authentication is used, SSH still performs key exchange.

The server and client negotiate encryption keys using algorithms like Diffie-Hellman (DH).

2️⃣ User Authentication Phase

After encryption keys are exchanged, the user authenticates using a username and password.

Why is the Answer FALSE?

❌ Even with password authentication, SSH still performs key exchange to establish an encrypted session.✅ The SSH session is always encrypted using cryptographic keys generated during KEX.

Real-World Application:

Secure Remote Access: Protects login credentials from MITM (Man-in-the-Middle) attacks.

Cloud & Datacenter Networks: Ensures secure SSH connections across remote infrastructure.

✅ Reference: Huawei HCIE-Datacom Guide – SSH Key Exchange and Authentication