H12-891_V1.0 HCIE-Datacom V1.0 Questions and Answers

Comprehensive and Detailed Explanation:

VGMP (Virtual Group Management Protocol)is used inHuawei firewallsforhot standby and high availability.

When is VGMP Activated?✔Whenhot standby is enabled, firewalls must synchronize their states to maintain failover capability.✅✔VGMPsends packets periodicallyto 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 isD.

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

In OSPFv3 (used for IPv6), Link LSAs (Type 8) are not advertised throughout the entire area. Instead, they are only advertised on a specific link (i.e., the local link). This differs from OSPFv2, where LSAs like Type 1 or Type 2 are advertised across the area.

Exact Extract - Huawei HCIE-Datacom V1.0 Courseware - Chapter: OSPFv3 Operation

“Link LSAs are generated by routers for each attached link and sent only on that link, not flooded throughout the area.”

Comprehensive and Detailed Explanation:

✔SRv6 Locator and Segment Structure:

TheSRv6 Locatoris2001: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 fieldsin Huawei SRv6.

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

✔Egress devicesinHuawei CloudCampus static IPsec VPNinclude:

Access Points (APs)

Routers

Firewalls✅

✔Why Firewalls?

Firewallssupport IPsec VPN terminationforsecure WAN interconnection.

Firewalls provideadvanced security filteringandencryptionfor IPsec traffic.

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

Understanding Inter-AS MPLS VPN Option C (Solution 2)

In MPLS L3VPN Inter-AS Option C, the Route Reflectors (RRs) are used for VPN route distribution but do not participate in data forwarding. The traffic forwarding path is based on MPLS labels assigned at different routers.

Each data packet carries two MPLS labels:

Transport Label (T1) – Used for forwarding within the backbone.

VPN Label (V1) – Used for VPN route identification.

Breaking Down the Labels:

✔VPN Label (V1) – Allocated by PE1 (Answer: C✅)

V1 (Inner Label) is the VPN label assigned by the egress PE router (PE1).

This label ensures that when the packet reaches PE1, it knows how to forward the traffic to CE1 (192.168.1.1).

✔Transport Label (T1) – Allocated by P2 (Answer: B✅)

T1 (Outer Label) is the transport label assigned by P2 to forward the packet across the AS core.

This label ensures the packet reaches the next-hop router (ASBR-PE1 in AS100).

Why Are the Other Options Incorrect?

❌A. "T1 is allocated by RR2" (Incorrect)

RR2 is used only for route reflection; it does not participate in label allocation or forwarding.

❌D. "V1 is allocated by P2" (Incorrect)

P2 is an intermediate router and does not allocate VPN labels.

VPN labels are always assigned by the egress PE router (PE1 in AS100).

????Reference:Huawei HCIE Datacom – MPLS L3VPN Inter-AS Option C

Comprehensive and Detailed In-Depth Explanation:

Analyzing the output:

A. The device sends sampled data every second:Correct. Thesample interval is 1000 ms (1 second).

B. The subscription name is Sub1:Correct. Thesubscription nameis clearly shown asSub1.

C. The subscription mode is static subscription:Correct. Since theSub-stateisPASSIVE, it indicates astatic subscription.

D. The IP address of the device is 192.168.56.1:Incorrect. The IP address192.168.56.1shown in the output is thedestination IPwhere the telemetry data is sent, not the IP address of the device itself.

Understanding the Network Scenario:

R2 is the boundary router between OSPF and IS-IS.

OSPF and IS-IS do not automatically redistribute routes between each other.

R4's loopback (10.1.4.4/32) exists in the IS-IS domain.

To allow R1 (OSPF) to reach R4’s loopback, R2 must redistribute IS-IS routes into OSPF.

Why Option C Is Correct (✅)

✔default-route-advertise in OSPF on R2:

This advertises a default route into the OSPF domain, allowing OSPF routers (R1, R3) to forward unknown traffic to R2.

Since IS-IS routes are not automatically injected into OSPF, this ensures R1 can reach R4.

✔IS-IS Already Has Routes to OSPF

IS-IS routers (R3, R4) already learn routes from OSPF via R2 (assuming route redistribution is properly configured).

No need to run default-route-advertise in IS-IS.

Why Other Options Are Incorrect (❌)

❌A. Run default-route-advertise in both OSPF and IS-IS views on R2

Unnecessary in IS-IS. The IS-IS domain already learns OSPF routes from R2 via redistribution.

Only OSPF needs a default route to forward unknown traffic to R2.

❌B. No configuration is required

Incorrect, because OSPF does not automatically learn IS-IS routes.

A default route or redistribution is needed for R1 to reach R4.

❌D. Run default-route-advertise only in the IS-IS view on R2

Incorrect, because IS-IS already has routing information from OSPF.

The issue is with OSPF not learning IS-IS routes, so the command needs to be in OSPF view.

????Reference:Huawei HCIE Datacom – OSPF and IS-IS Route Redistribution and Interoperability

Understanding Huawei SD-WAN VN (Virtual Network) Topologies

Huawei SD-WANusesVirtual Networks (VNs)to providetraffic isolation and policy-based routingfor different services, branches, and applications.

????VN Topologies Can Be Different

Each VN (Virtual Network) can have its own topology.

Some VNs may usefull-mesh, while others may usehub-and-spokeorstar topology.

Different VNs can havedifferent routing and security policies.

✅Example:

Corporate traffic (VN1)→Full-mesh topologyfor efficient inter-branch communication.

Guest Wi-Fi traffic (VN2)→Hub-and-spoke topologyto restrict inter-site communication.

Why is the Answer FALSE?

❌All VNs do not have to use the same topology.

✅Each VN can be configured independently with a unique topology, routing policy, and security settings.

✅Reference:Huawei HCIE-Datacom Guide – SD-WAN VN Topologies and Segmentation

Authentication Header (AH) in IPsec

TheAuthentication Header (AH) protocolis part ofIPsecand providesauthentication, integrity, and replay protectionbutdoes NOT provide encryption.

✅B. AH provides data origin authentication.

Ensures thatpackets come from a trusted sourceusing cryptographic signatures.

✅C. AH provides anti-replay protection.

Usessequence numbersto prevent attackers from replaying old packets.

✅D. AH provides data integrity authentication.

Ensuresdata integrityby verifying that packetshave not been tampered withduring 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

HuaweiSD-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 IPsecisthe primary tunneling method used in Huawei SD-WAN.

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

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

X = 0

Y = 0

Z = 1

Understanding MPLS Label Headers

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

MPLS is ahigh-performance forwarding technologythat replacesIP lookups with label switching.

Packets are forwardedbased on labels instead of destination IP addresses.

MPLS labels are stacked when passing throughmultiple hops.

????MPLS Label Stack Structure

Each MPLS label hasfour fields:

Label– 20-bit identifier used for forwarding.

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

S (Bottom of Stack)– 1-bit flag that indicates whether this is thelast (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 anEXP 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 thedefault value of 0.

Thebottom 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 determinepacket priorityinService Provider networks.

Traffic Engineering (TE):MPLS labels guide packets throughoptimized paths, ensuringlow-latency services.

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

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

Understanding Huawei’s Free Mobility Solution

Huawei’sFree Mobility solutionis designed to ensure that users can seamlesslyaccess the networkregardless of their physical location while maintainingconsistent policies.

????Key Components in Free Mobility Solution:

1️⃣iMaster NCE-Campus (Answer A - Core Role)

Manages network policies & user access.

Implementscentralized policy control & orchestration.

2️⃣Policy Enforcement Device (Answer B - Core Role)

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

Typically aswitch or gatewayenforcing access control.

3️⃣Policy Control Device (Answer D - Core Role)

Stores anddynamically assigns policies based on user role & device type.

Works closely withiMaster NCE-Campus.

????Why is C (Authentication Device) NOT a Core Role?

❌Authentication devices (such as aRADIUS or AAA server) arenot a core componentof Huawei’sFree Mobilitysolution.

They are part of thebroader network security frameworkbutnot mandatoryfor Free Mobility.

Real-World Application:

Used inenterprise & campus networkswhereemployees, guests, and IoT devices need seamless accesswhile maintaining security policies.

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

To analyze this question, let's break down the key concepts and the given LSDB (Link State Database) information from the figure:

Understanding the LSDB Output:

The output shows the OSPF LSDB on R2 with Router ID 10.1.123.2.

Area 0.0.0.0 (Area 0) is displayed along with several Link State Advertisements (LSAs) including Router LSAs, Network LSAs, and Summary LSAs.

Area 0.0.0.1 (Area 1) also displays Router LSAs and a Type 7 LSA (NSSA LSA) with Link-State ID 0.0.0.0.

An External LSA (Type 5) with Link-State ID 0.0.0.0 and AdvRouter 10.1.123.2 is also present.

Analysis of Each Option:

Option A: Area 1 is an NSSA.

Correct.

The presence of a Type 7 LSA (NSSA LSA) in the database indicates that Area 1 is configured as an NSSA (Not-So-Stubby Area).

NSSA allows the injection of Type 7 LSAs for external routes while blocking Type 5 LSAs from entering the area.

Option B: R2 translates Type 7 default route into Type 5 default route.

Correct.

In an NSSA, if an ABR (like R2) has the NSSA ASBR capability, it will convert Type 7 LSAs to Type 5 LSAs before injecting them into the backbone area (Area 0).

In the LSDB, we see both a Type 7 LSA (NSSA) and a corresponding Type 5 External LSA, confirming that R2 performs this translation.

Option C: R2 advertises the default route in the OSPF process.

Incorrect.

There is no indication that R2 itself is originating the default route.

The Type 7 LSA in Area 1 and the Type 5 LSA in Area 0 only indicate translation from another source, not R2 advertising it directly.

Option D: Area 1 does not have Type 3 LSAs. The possible cause is that R2 filters Type 3 LSAs in the outbound direction of Area 1.

Incorrect.

In an NSSA area, Type 3 LSAs (Inter-Area Prefix LSAs) are typically not generated for external routes.

The absence of Type 3 LSAs in Area 1 is due to the nature of NSSA itself rather than any filtering configured on R2.

Comparison Between Paramiko (SSH) and Telnetlib (Telnet)

✅Paramiko (SSH) is more secure than Telnetlib (Telnet).

SSH (Secure Shell) encrypts login credentials and session datausing encryption protocols likeAES and RSA.

Telnet transmits data in plaintext, making it vulnerable to eavesdropping and man-in-the-middle attacks.

✅Why is Telnet Insecure?

No encryption→ Credentials (username/password) are sent in plaintext.

Easily interceptedby attackers using packet sniffers (e.g., Wireshark).

Correct Method for Secure Remote Login in Python:

UseParamiko for SSH-based secure automation.

Example of logging in withParamiko (SSH)in Python:

import paramiko

ssh = paramiko.SSHClient()

ssh.set_missing_host_key_policy(paramiko.AutoAddPolicy())

ssh.connect("192.168.1.1", username="admin", password="password")

stdin, stdout, stderr = ssh.exec_command("display version")

print(stdout.read().decode())

ssh.close()

Reference from Huawei HCIE-Datacom Documentation:

Huawei Security Best Practices – Avoiding Telnet and Using SSH for Secure Access

HCIE-Datacom Training Material – Network Automation with Python (Paramiko & Telnetlib)

Understanding NETCONF Operation Attributes

????What is NETCONF?

NETCONF (Network Configuration Protocol)is anIETF-standardized protocolfor network automation.

Uses XML-based configuration transactions with operations.

????Common NETCONF Operation Attributes:

✅A. create→ Adds new data but fails if it already exists.

✅B. delete→ Removes the specified data from the configuration datastore.

✅C. merge→ Updates existing data or creates it if it does not exist.

❌D. remove (Incorrect Choice)

NETCONF does not support remove as an operation.

delete is the correct operation for removing data.

Why is the Answer A, B, C?

✅NETCONF supports create, delete, and merge, but NOT remove.

Real-World Application:

SDN Controllers & Network Automation:Uses NETCONF to configure devices dynamically.

Huawei iMaster NCE-WAN:Automatesdevice onboarding and template-based configurations.

✅Reference:Huawei HCIE-Datacom Guide – NETCONF Protocol and Configuration Operations

Intra-Area-Prefix-LSA (Type 9) is used in OSPFv3 to carry IPv6 prefix information for a router or network and is flooded within the area.

Link-LSA (Type 8) is only sent on the local link and is not flooded throughout the area.

Inter-Area-Prefix-LSA (Type 3) and Inter-Area-Router-LSA (Type 4) are also flooded within an area but originate from ABRs, typically for cross-area route advertisement.

That said, Intra-Area-Prefix-LSA is specifically flooded within an area, matching the context of the question directly.

Exact Extract - Huawei HCIE-Datacom OSPFv3 Module:

“Intra-Area-Prefix-LSAs are flooded within the area and advertise the IPv6 prefixes associated with router and network LSAs.”

Comprehensive and Detailed In-Depth Explanation:

To supportSR-MPLS (Segment Routing over MPLS),OSPFusesType 10 Opaque LSAsto advertiseSegment Routing (SR) capabilities and information.

Type 10 Opaque LSA (B): Used fordistributing application-specific informationwithin an OSPF area. In SR-MPLS, it carries theSID/Label mappingsand other SR-related information.

Type 7 NSSA External LSA (A):Used to advertise external routes within an NSSA, not related to SR-MPLS.

Type 1 Router LSA (C):Advertises the router’s interfaces and links but does not carry SR-specific information.

Type 2 Network LSA (D):Advertises the links of abroadcast or NBMA network, not used for SR-MPLS.

Therefore, the correct answer isB (Type 10 Opaque LSA), as it enables theadvertisement of SR information.

Comprehensive and Detailed Explanation:

R2 is anArea Border Router (ABR), meaning itconnects multiple OSPF areas(Area 0 and Area 1).

ABRs generate Router-LSAs for each area they belong to.

SinceR2 is part of both Area 0 and Area 1, it must generateRouter-LSAs (Type 1) for both areas.

R2 does not forward Router-LSAs between areas; instead, it generatesSummary LSAs (Type 3)to exchange routing information between areas.

Thus, the correct answer isD.

????Reference:Huawei HCIE Datacom – OSPF LSA Types and ABR Behavior

Comprehensive and Detailed Explanation:

✔Hub-Spoke networkingis the mostefficient and scalablemodel for interconnecting100+ branchesin asmall and midsize campus network.

✔Why Hub-Spoke?

Centralized Control:Ahub routermanages communication betweenspoke routers(branch sites).

Reduced Complexity:Unlikefull-mesh, which requiresN(N-1)/2* connections,hub-spoke minimizes link costs.

Easier Management:Policy enforcement and security are centralized at thehub site.

✔Why Not Other Options?

❌A (Direct Networking)→ Suitable forsmall networks, but inefficient for100+ branches.

❌B (Full-Mesh Networking)→ Highcost and complexity, requiringtoo many links.

❌D (Partial-Mesh Networking)→ More scalable thanfull-mesh, buthub-spoke is more optimizedfor large branch networks.

????Reference:Huawei HCIE Datacom – WAN Interconnection Models

Understanding SRv6 (Segment Routing over IPv6) Policies

????What is an SRv6 Policy?

Atraffic engineering (TE) mechanismused inSRv6-enabled networks.

Defines a set ofSegment Routing (SR) pathsthat direct packets through a predefined set of waypoints.

UsesSRv6 SIDs (Segment Identifiers)instead of MPLS labels.

????How Can SRv6 Policies Be Configured?

✅Static SRv6 Policy Configuration:

Manually configured by network administrators.

Used inpredictable, fixed network paths.

✅Dynamic SRv6 Policy Generation:

Created dynamically by anSDN controller(e.g.,Huawei iMaster NCE).

The controlleranalyzes network conditionsandadjusts paths automaticallybased on traffic load and link failures.

Why is the Answer TRUE?

✅SRv6 policies can be configured manually or dynamically delivered by a controller.

✅SDN-based SRv6 solutions improve network automation and traffic engineering efficiency.

Real-World Application:

Cloud Data Centers:Usesdynamic SRv6 policiesfor optimal traffic distribution.

5G Transport Networks:UsesSRv6 TE for low-latency service guarantees.

✅Reference:Huawei HCIE-Datacom Guide – SRv6 Policy and SDN Integration

Comprehensive and Detailed In-Depth Explanation:

BGP4+ (BGP for IPv6) uses theMP_REACH_NLRI(Multiprotocol Reachable Network Layer Reachability Information) attribute to advertise IPv6 routes. This attribute is part of BGP's multiprotocol extensions (RFC 2858), allowing BGP to support multiple address families, including IPv6.

MP_REACH_NLRI:Advertises reachable IPv6 prefixes along with next-hop information.

MP_UNREACH_NLRI:Used to withdraw previously advertised IPv6 routes.

Since IPv6 addresses are significantly different from IPv4 addresses in structure and length (128 bits), the traditional BGP update message format (which supports only IPv4) is insufficient. TheMP_REACH_NLRIattribute solves this by carrying IPv6-specific information.

Comprehensive and Detailed Explanation:

Port isolationis a feature used to enhance security andnetwork segmentationby restricting communication between certain switch ports atLayer 2while allowing them to communicate throughLayer 3.

Layer 2 Communication:Devices within the same VLAN can communicate with an upstream gateway or router.

Layer 3 Isolation:Devices cannot communicatedirectlyat Layer 2 but must pass through a Layer 3 device (e.g., a router or firewall).

Use Case:Typically used in enterprise networks, hotel networks, and campus networks to preventunwanted direct communicationbetween clients.

Thus, the statement iscorrect, and the answer isTRUE.

????Reference:Huawei HCIE Datacom Official Guide - Ethernet Port Isolation

Challenges of Static VXLAN Tunnel Configuration

Astatic VXLAN tunnelrequires manualVTEP-to-VTEP configuration, making it complex to maintain.

✅A. Heavy configuration workload in a distributed gateway scenario

Static VXLAN requires manual configuration of VTEP mappings, making itdifficult to scale and adjustwhen adding new VTEPs.

✅B. Remote MAC addresses are learned through data flooding

UnlikeBGP EVPN-based VXLAN, whichadvertises MAC/IP bindings through BGP,static VXLAN relies on flooding for MAC learning, causingexcessive traffic.

✅D. N(N-1)/2 tunnels are required for full mesh connectivity

IfN devices need to communicate, each must be manually configured withN(N-1)/2 VXLAN tunnels, leading tohigh administrative overhead.

Incorrect Statement Explanation:

❌C. Static VXLAN tunnels use protocols on the control plane, consuming device resources.

Wrong!Static VXLANdoes not use a control plane protocollike BGP EVPN.

Instead,it relies entirely on static mappings, reducing control plane usage.

Reference from Huawei HCIE-Datacom Documentation:

Huawei VXLAN Configuration Guide – Static vs. Dynamic VXLAN Tunnel Establishment

HCIE-Datacom Training Material – Manual Configuration Challenges in Static VXLAN

VXLAN Inter-Subnet Routing with Symmetric IRB

VXLAN supportsinter-subnet routingusingIntegrated Routing and Bridging (IRB). Insymmetric IRB, both ingress and egress VTEPs performLayer 3 forwardingto ensure efficient packet forwarding across subnets.

✅A. Both the ingress VTEP and egress VTEP forward packets based on the Layer 3 forwarding table.

Insymmetric IRB, bothingress and egress VTEPs perform Layer 3 lookup and forwarding.

The ingressroutes packets before encapsulating them in VXLAN, and the egressperforms another Layer 3 lookup to determine final delivery.

✅D. When VTEPs forward inter-subnet user communication packets, the VNI carried in the VXLAN header is the L3VNI.

L3VNI (Layer 3 VXLAN Network Identifier)is used forinter-subnet routingbetween VXLAN segments.

In Huawei’sCloudCampus Solution, VNs (Virtual Networks) areisolated by defaultfor security purposes. To enableinter-VN communication, you must explicitly configure policies that allow traffic between different VNs.

The correct way to control and enable this communication is viarouting policies, especiallyinter-VN routing policieson thecore or border nodes.

Static routesorOSPF deploymentsare not sufficient or appropriate for policy-controlled VN communication in this context.

Correct answer: D. Deploy a routing policy

Understanding Network Security for Authorized User Access

????Problem Scenario:

Only authorized users should be allowed network access.

Users can obtain IP addresses either via DHCP or a predefined static IP list.

Unauthorized users (e.g., attackers using rogue DHCP servers or spoofed IPs) must be blocked.

????Required Technologies for Securing Access:

1️⃣DHCP Snooping– Protects againstrogue DHCP serversand builds abinding table of legitimate DHCP clients.

2️⃣IP Source Guard (IPSG)– Ensures that onlyauthorized IP-MAC bindingscan send traffic.

Analysis of the Answer Choices:

❌A. DAI + Port Security (Incorrect)

DAI (Dynamic ARP Inspection)prevents ARP spoofingbut doesnot validate IP-MAC-DHCP bindings.

Port Securityonlylimits MAC addresses per portbut doesnot verify IP addresses.

Does NOT protect against unauthorized static IP users.

✅B. DHCP Snooping + IPSG (Correct)

DHCP Snooping:

Preventsrogue DHCP servers from assigning unauthorized IPs.

Builds aDHCP binding table(IP-MAC-Port).

IP Source Guard (IPSG):

Blocks trafficfrom IPs not listed in the DHCP snooping binding table.

Can be configured to allow manually specified static IP addresses.

Best choice to allow only authorized users (both DHCP and static IP users).

❌C. DHCP Snooping + DAI (Incorrect)

DAI (Dynamic ARP Inspection) prevents ARP spoofingbutdoes not block unauthorized static IP users.

Lacks IP-level access controlneeded to enforce static IP policies.

❌D. DAI + IPSG (Incorrect)

IPSG (IP Source Guard) needs DHCP Snooping to build the binding table.

Without DHCP Snooping, IPSG cannot function properly.

DAI does not provide complete protection against unauthorized users.

Why is the Answer B (DHCP Snooping + IPSG)?

✅Ensures only users assigned a DHCP IP (or authorized static IPs) can send traffic.

✅Blocks rogue DHCP servers and unauthorized static IP users.

Real-World Application:

Enterprise Networks:Prevents unauthorizedstatic IP users or attackers from accessing VLANs.

Public Wi-Fi Security:Ensures onlyauthorized users receive IPs and can send traffic.

✅Reference:Huawei HCIE-Datacom Guide – DHCP Snooping and IPSG Security Mechanisms

Huawei SD-WAN supports various intelligent traffic steering mechanismsto optimize link utilization andbalance network trafficacross multiple links.

✅D. Traffic bandwidth-based traffic steering

This method ensures that traffic isdistributed across multiple links based on available bandwidth.

SD-WAN dynamically selects linksbased on their real-time bandwidth utilization,ensuring optimal performance and load balancing.

Understanding SR-MPLS Label Calculation

SR-MPLS usesSegment Routing Global Block (SRGB)andPrefix SIDsto assign labels dynamically. TheMPLS labelfor 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, theMPLS 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 withinR3’s SRGB range.

❌Using the Prefix SID Index directly (30)

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

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

Comprehensive and Detailed Explanation:

✔Portal authenticationis aweb-based authentication mechanismused in campus networks tocontrol user access.

✔Correct Statements:

✅(A)ThePortal server exchanges authentication detailswith the access device, which forwards them to the authentication server.

✅(D)When usingHTTP/HTTPS authentication, the client must send authentication credentials to theaccess device, which then forwards them to the authentication server.

✔Incorrect Statements:

❌(B)HTTP/HTTPS support ismandatoryfor web-based authentication.

❌(C)If HTTP/HTTPS is used,Portal authentication may still be required.

????Reference:Huawei HCIE Datacom – Portal Authentication Mechanism

Understanding VXLAN and ARP Suppression in BGP EVPN

VXLAN (Virtual Extensible LAN) is used toextend Layer 2 networks over Layer 3 infrastructure.

VXLAN uses VTEPs (VXLAN Tunnel Endpoints) to encapsulate and forward Layer 2 traffic.

BGP EVPN (Ethernet VPN)is used forMAC/IP address learning and distributionacross VXLAN networks.

How ARP Request Forwarding Works in This Scenario?

1️⃣ARP Broadcast Suppression Enabled (VXLAN Optimized Forwarding)

SinceARP broadcast suppressionis enabled onVTEP1, theARP request is not flooded.

Instead, VTEP1checks its EVPN learned databaseto findPC2’s MAC address (MAC C).

2️⃣VTEP1 Encapsulates the ARP Request

VTEP1encapsulates the ARP request in a VXLAN packetand sends it toVTEP2.

Theoriginal ARP frame inside the VXLAN tunnel still has:

Source MAC:MAC A(PC1's MAC)

Destination MAC:MAC C(PC2's MAC, learned via EVPN)

3️⃣VXLAN Outer Headers

Theouter VXLAN headeruses:

Source IP:1.1.1.1 (VTEP1)

Destination IP:2.2.2.2 (VTEP2)

VNI (VXLAN Network Identifier):200(BD 20)

4️⃣VTEP2 Receives and Forwards the ARP Request

VTEP2 decapsulates the VXLAN packetand forwards theoriginal ARP requesttoPC2 (MAC C).

This ensures thatonly the intended receiver (PC2) gets the ARP request, preventing unnecessary broadcast flooding.

Why the Answer is MAC C?

✅B. MAC C is Correct

Thedestination MAC of the inner data frameisPC2’s MAC (MAC C).

This is becauseVTEP1 forwards the ARP request directly to VTEP2, which then forwards it to PC2.

Why Other Answers Are Incorrect?

❌A. MAC B (Incorrect)

MAC B is VTEP1’s MAC address, which is used in theouter VXLAN header, not in the inner Ethernet frame.

❌C. MAC A (Incorrect)

MAC A is the source MACof the ARP request (PC1), not the destination.

❌D. MAC D (Incorrect)

MAC D is not mentioned in the topology, so it is irrelevant.

????Reference:Huawei HCIE Datacom – VXLAN BGP EVPN and ARP Suppression

Understanding OSPF Neighbor States

OSPF (Open Shortest Path First) establishes neighbor relationships through several states:

1️⃣Down:No Hello packets received.

2️⃣Init:Routerreceives Hello packetsbutits own Router ID is missingin the received packets.

3️⃣2-Way:Routerssee each other in Hello packets. (Stable state for non-DR/non-BDR routers).

4️⃣ExStart:Routersstart exchanging LSAsbut may faceMTU mismatches.

5️⃣Exchange:Routers sendDatabase Description (DBD) packetsto synchronize link-state databases.

6️⃣Loading:Routers exchangeLink-State Requests (LSRs) & Updates (LSUs)to fully sync.

7️⃣Full:Routers are fully synchronized.

Analysis of the Answer Choices

✅A. For non-DR and non-BDR routers on an Ethernet link, the 2-Way state is acceptable.

Correct:Non-DR/Non-BDR routers remain in2-Way statesince they don’t need to form full adjacency.

✅B. The Init state indicates that the router has received Hello packets from its neighbors, but the received Hello packets do not contain the OSPF RID of the receiving router.

Correct:If an OSPF router receives a Hello butdoes not see its own Router ID, it stays in theInit state.

✅C. The ExStart state indicates that two neighbor routers have inconsistent MTUs or the same OSPF Router ID (RID).

Correct:If MTUs mismatch or RIDs conflict, theDBD exchange fails, causing routers to remain inExStart state.

❌D. The Attempt state indicates that the router does not send unicast Hello packets to configured neighbors.

Incorrect:

InAttempt state, routerssend unicast Hello packetsto manually configured neighbors (common inNBMA networks).

If no Hello responses are received, they remain inAttempt state, but theyDO send Hellos.

Real-World Application

OSPF Troubleshooting:Identifying routers stuck inInit or ExStart statescan point toMTU mismatches or neighbor misconfigurations.

NBMA Networks (Frame Relay, DMVPN):Manually configured neighbors may stay inAttempt state if Hello packets are lost.

✅Reference:Huawei HCIE-Datacom Study Guide – OSPF Neighbor States & Troubleshooting

FEC (Forwarding Equivalence Class) in MPLS is a group of packets that are forwarded in the same manner. MPLS can classify packets into FECs based on factors such as:

Destination IP address

Source address

CoS (Class of Service)

Application type

However, Fragment Offset, which is part of the IP header used for IP fragmentation, is not used in FEC classification. Fragment offset is more relevant to how IP packets are reconstructed and not suitable or used as a classification standard for forwarding decisions in MPLS.

Exact Extract - Huawei HCIE-Datacom V1.0 MPLS Chapter:

“FEC classification may be based on various parameters including destination address, source address, and even CoS values. However, fragment offset is not used as an FEC criterion, as MPLS forwarding occurs before IP reassembly.”

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 In-Depth Explanation:

TheOutbound Route Filtering (ORF)function in BGP allows a BGP speaker to inform its peer about the prefixes that it wants to receive, thereby reducing unnecessary route advertisements.

IP Prefix-List (D)is the correct answer because it is used to define the list of prefixes that are sent to the BGP peer during theORF capability negotiation.

Filter-policy (A)andRoute-policy (B)are used for controlling routing information locally or filtering incoming/outgoing routes but do not directly control the number of routes sent using ORF.

ACL (C)is primarily used for packet filtering and is not related to BGP route filtering.

Comprehensive and Detailed In-Depth Explanation:

NSR (Non-Stop Routing)andNSF (Non-Stop Forwarding)are high-availability mechanisms used to maintain network stability during routing process failures:

NSR (Non-Stop Routing):

Operates within thelocal router only.

Keeps routing information synchronized between theactive and standby processes.

Does not require collaboration from neighboring routers.

NSF (Non-Stop Forwarding):

Requires collaboration from neighboring routersthat support graceful restart.

The router undergoing failover relies on its neighbors tomaintain forwarding tableswhile control plane recovery takes place.

Neighboring routers must supportGR (Graceful Restart)for NSF to function correctly.

Therefore, the correct answer isBbecauseNSF requires neighboring router collaboration, whileNSR does not.

Comprehensive and Detailed Explanation:

iMaster NCE-CampusInsightis Huawei'sintelligent network analysis platformthat:

✔Collectsreal-time telemetry datausingSNMP, NetStream, and Telemetry.

✔Analyzes traffic patternsto detect network anomalies.

✔UsesAI-driven analyticsto optimize network performance.

Thus, the statement isTRUE.

????Reference:Huawei HCIE Datacom – iMaster NCE-CampusInsight Features

Network Slicing Using Channelized Sub-Interfaces and FlexE

Bothchannelized sub-interfacesandFlexE (Flexible Ethernet)are used fornetwork slicing, but they have differentapplication scenarios:

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

Channelized sub-interfacessplit a physical interfaceinto multiple logical sub-interfaces.

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

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

FlexEdivides 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 HTTP/1.1 Response Headers

????What is an HTTP Response?

When a web server responds to an HTTP request, itsends an HTTP response message.

The response containsheaders, a status line, and a response body.

Elements of an HTTP Response Header:

✅A. Status Code→Correct

Indicates the response status (e.g., 200 OK, 404 Not Found).

✅B. Reason Phrase→Correct

Provides ahuman-readable explanationof the status code (e.g., OK, Not Found).

✅C. Protocol Version→Correct

Specifieswhich HTTP version is being used(e.g., HTTP/1.1).

❌D. Response Method→Incorrect

TheHTTP method (GET, POST, etc.) is part of the request, not the response.

IS-IS Multi-Process:

Huawei devices support runningmultiple IS-IS processes simultaneously.

These processes arecompletely independentof one another: different LSDBs, interfaces, routing tables, etc.

Each process can be associated with aseparate VPN instance, and asingle VPN instance can be served by multiple IS-IS processes.

IS-IS Multi-Instance:

One IS-IS process canrun multiple instances, typically used formulti-VPN scenarios.

However, Huawei's current implementation prefersone VPN per processfor clarity and control.

Based on Huawei’s design:

Ais incorrect — an IS-IS processcanserve multiple VPNs in other vendors, but Huawei typically uses one process per VPN for clean separation.

Bis correct — a VPN instance can be associated withmultiple IS-IS processes.

Cis incorrect in Huawei implementation context.

Dis correct —IS-IS processes are independent.

Correct answers: B, D

Understanding EVPN (Ethernet VPN) Label Allocation and ARP Handling

????What Happens in This Scenario?

1️⃣CE1 (192.168.1.1) sends an ARP request to discover the MAC address of CE2 (192.168.1.2).

2️⃣PE1 receives the ARP request and needs to forward it over the EVPN fabric.

3️⃣To send the broadcast ARP request across the EVPN network, PE1 forwards the packet to PE4 using BUM (Broadcast, Unknown unicast, and Multicast) forwarding.

4️⃣PE4, as the Designated Forwarder (DF), forwards the ARP request to CE2.

Role of Labels in EVPN VXLAN/MPLS Networks

????EVPN uses BGP to distribute MAC/IP reachability information using different route types.

✅EVPN Type 2 Route (MAC/IP Advertisement Route):

Used forMAC-to-IP address mappingannouncements.

Ensuresremote VTEPs (PE routers) learn MAC-to-IP bindingsdynamically.

✅EVPN Type 3 Route (Inclusive Multicast Route):

Used forBUM traffic (Broadcast, Unknown Unicast, Multicast).

Assigns a multicast label (e.g., 201) to be used for forwarding broadcast packets like ARP requests.

????In this case:

Thelabel 201is used forBUM traffic forwarding.

BUM traffic is handled using an EVPN Type 3 route.

Why is the Answer 3?

✅EVPN Type 3 routes carry labels for BUM traffic, which includes ARP requests.

✅Label 201 is used for multicast distribution, which is managed by Type 3 routes.

Real-World Application:

VXLAN Data Centers:UsesEVPN Type 3 routes to control BUM traffic efficiently.

Campus Networks:Preventsunnecessary flooding of ARP requests across VXLAN domains.

✅Reference:Huawei HCIE-Datacom Guide – EVPN BGP Route Types and Multicast Labeling

Analyzing the Routing Table Output:

The command display ipv6 routing-table protocol isis showsall IPv6 routes learned via IS-IS.

The output shows"Summary Count: 6", meaning R1 hassix IS-IS IPv6 routes.

Explanation of Correct Answers:✅A. R1 has six IS-IS IPv6 routes.

The "Summary Count: 6" confirms thatsix IS-IS IPv6 routes existin R1's routing table.

✅C. IS-IS IPv6 must have been enabled on GigabitEthernet0/0/1 of R1.

Theinterface GigabitEthernet0/0/1is listed as thenext-hop, meaning IS-IS IPv6 must beenabled on that interface.

✅D. R1 is not a Level-1 device.

The protocol is listed as"ISIS-L2", indicating that R1 is anIS-IS Level-2 (backbone) router,not a Level-1 router.

Incorrect Answer Explanation:❌B. R1 does not have IS-IS IPv6 routes.

Wrong!The output clearlyshows six IS-IS IPv6 routes, proving this statement false.

Reference from Huawei HCIE-Datacom Documentation:

Huawei IPv6 Routing Protocols Guide – IS-IS for IPv6

HCIE-Datacom Routing & Switching Training – IS-IS L1 & L2 Operations

Huawei IS-IS Configuration Guide – IPv6 Route Management

Comprehensive and Detailed In-Depth Explanation:

TheHuawei SD-WAN SolutionusesHTTP/2as the primary protocol toreport device performance datato the controller.

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

It supportsbidirectional communicationbetween devices and the iMaster NCE-Campus controller.

While protocols likeNetFlowandSNMPare traditionally used for monitoring, Huawei SD-WAN specifically usesHTTP/2for real-time performance reporting and control due to its modern web-based architecture.

A screenshot of a computer AI-generated content may be incorrect.

Comprehensive and Detailed In-Depth Explanation:

ThegRPC-based telemetry protocolutilizesprotocol buffers (.proto files)to define the structure and data format used in communication between a client and a server. In Huawei's telemetry architecture, these files are categorized based on their roles in the data model.

1. RPC Layer:

File:huawei-grpc-dialin.proto

TheRPC layer (Remote Procedure Call layer)handles communication between the client and server.

The filehuawei-grpc-dialin.protodefines thegRPC service interfaces, message structures, and procedures for remote method invocation.

It is essential forestablishing communicationandinvoking telemetry data collection.

Function:Managesdial-in and dial-out connectionsbetween the telemetry client and the server.

2. Telemetry Layer:

File:huawei-telemetry.proto

Thetelemetry layeris responsible forcollecting, packaging, and exporting telemetry data.

The filehuawei-telemetry.protocontains thedata modelused for telemetry reporting, includingstreaming data formatsandtelemetry messages.

It defines how thecollected datais organized and transmitted.

Function:Provides astructured way to export telemetry datain real-time or batch mode.

3. Service Data Layer:

File:huawei-debug.proto

Theservice data layercontains data models related todiagnostics, debugging, and operational data.

The filehuawei-debug.protois used tocollect debugging informationfrom network devices.

This file is crucial fortroubleshooting and monitoring the healthof the system.

Function:Facilitatesdebugging and diagnostic telemetry data collection.

Why This Mapping Is Correct:

The mapping is based on thefunctional role of each layerand thepurpose of each .proto filein the Huawei gRPC-based telemetry architecture.

Correctly identifying the file location is crucial foreffective telemetry configurationanddata collection.

To determine R3’s role (Level-1, Level-2, or Level-1-2) based on the provided output of the display ipv6 routing-table protocol isis command on R3, we need to analyze the IS-IS routing information and understand IS-IS hierarchy and behavior, particularly in the context of IPv6 routing. Let’s break it down step by step:

Understanding the IS-IS Levels and Hierarchy:

IS-IS (Intermediate System to Intermediate System) is a link-state routing protocol that supports a two-level hierarchy:

Level-1: Routers within the same area, responsible for intra-area routing. Level-1 routers only maintain routing information for their area and rely on Level-1-2 routers to reach other areas.

Level-2: Routers that form the backbone, connecting different areas for inter-area routing. Level-2 routers maintain routing information across areas.

Level-1-2: Routers that operate both at Level-1 (within their area) and Level-2 (to connect to other areas). These routers act as boundary routers between Level-1 areas and the Level-2 backbone.

A router’s role (Level-1, Level-2, or Level-1-2) determines which types of adjacencies it can form and what routing information it advertises or receives.

Analyzing the Output:

The output shows R3’s IPv6 routing table with routes learned via IS-IS, specifically:

Destination: 2082:EDFC:DDCC::B824:0/127, Protocol: ISIS-L1

This route is learned via IS-IS Level-1 (ISIS-L1), indicating that R3 has a Level-1 adjacency and is receiving or advertising routes within its area.

The next hop (FE80::2E0:FCFF:FE45:6A3E) and interface (GigabitEthernet0/0/0) suggest this route is intra-area.

Destination: 2082:EDFC:DDCC::B891:0/127, Protocol: ISIS-L2

This route is learned via IS-IS Level-2 (ISIS-L2), indicating that R3 has a Level-2 adjacency and is receiving or advertising routes for inter-area or backbone routing.

The next hop (FE80::2E0:FCFF:FE50:406F) and interface (GigabitEthernet0/0/1) suggest this route is for a different area or the backbone.

Both Level-1 and Level-2 routes are present in R3’s routing table, which provides critical insight into R3’s role.

Determining R3’s Role:

Level-1 Routers:

Level-1 routers only participate in Level-1 adjacencies and maintain routing information for their area. They do not have Level-2 routes or adjacencies unless connected to a Level-1-2 router. Since R3 has a Level-2 route (ISIS-L2), it cannot be exclusively a Level-1 router.

Level-2 Routers:

Level-2 routers focus on inter-area routing and typically do not maintain Level-1 routes unless they are also configured as Level-1-2. Since R3 has a Level-1 route (ISIS-L1), it cannot be exclusively a Level-2 router.

Level-1-2 Routers:

Level-1-2 routers operate both at Level-1 (for intra-area routing) and Level-2 (for inter-area routing). They can form adjacencies with both Level-1 and Level-2 neighbors and maintain both types of routes. The presence of both ISIS-L1 and ISIS-L2 routes in R3’s routing table indicates that R3 is participating in both Level-1 and Level-2 adjacencies, making it a Level-1-2 router.

Evaluating Each Option:

A. R3 must be a Level-2 device.

This is incorrect because R3 has ISIS-L1 routes, indicating it is also participating in Level-1 adjacencies, which Level-2-only devices do not do. Level-2 devices focus solely on inter-area routing and do not maintain Level-1 routes.

B. The device role of R3 cannot be determined.

This is incorrect because the presence of both ISIS-L1 and ISIS-L2 routes in the routing table clearly indicates R3’s role. The combination of Level-1 and Level-2 routes confirms R3 is a Level-1-2 router.

C. R3 must be a Level-1-2 device.

This is correct. The routing table shows both ISIS-L1 (Level-1) and ISIS-L2 (Level-2) routes, meaning R3 is operating as both a Level-1 and Level-2 router, which defines a Level-1-2 device.

D. R3 must be a Level-1 device.

This is incorrect because R3 has ISIS-L2 routes, indicating it is also participating in Level-2 adjacencies, which Level-1-only devices do not do. Level-1 devices only maintain intra-area routes and rely on Level-1-2 routers for inter-area reachability.

Additional Considerations:

The Flags: D in the output typically indicates a directly connected route or a route downloaded to the forwarding table, but it does not affect the determination of R3’s IS-IS level.

The preference (15) and cost (20) are standard for IS-IS routes and do not impact the level determination.

In Huawei’s IS-IS implementation, routers can be configured explicitly as Level-1, Level-2, or Level-1-2 using commands like isis level-1-2 under the IS-IS process. The presence of both Level-1 and Level-2 routes confirms R3’s configuration as Level-1-2.

Huawei HCIE-Datacom Context:

According to Huawei HCIE-Datacom documentation, IS-IS routers can operate at different levels, and the routing table’s protocol type (ISIS-L1 or ISIS-L2) indicates the level of adjacency. A router with both Level-1 and Level-2 routes is necessarily a Level-1-2 device, as it participates in both intra-area and inter-area routing.

The display ipv6 routing-table protocol isis command on Huawei devices shows routes learned via IS-IS, and the protocol type (L1 or L2) directly reflects the router’s role in the IS-IS hierarchy.

Conclusion:

Based on the presence of both ISIS-L1 and ISIS-L2 routes in R3’s IPv6 routing table, R3 must be a Level-1-2 device, as it is participating in both Level-1 (intra-area) and Level-2 (inter-area) adjacencies. Therefore, the correct answer is C.

References to Huawei HCIE-Datacom Documents:

Huawei HCIE-Datacom V1.0 Training Material, Chapter on IS-IS Configuration and Hierarchy.

Huawei NE Series Router Configuration Guide, IS-IS Section (Level-1, Level-2, and Level-1-2 Operations).

Huawei Technical Whitepaper on IS-IS Protocol, discussing IPv6 Routing and Level Determination.

Huawei AR routers used as egress gateways in CloudCampus solutions support multiple onboarding and deployment methods, including:

DHCP Option 148-based auto-deployment

Web-based management

CLI-based deployment and configuration (also supported)

So, the statement is incorrect—CLI-based deployment is supported.

Exact Extract - Huawei CloudCampus AR Router Deployment Guide:

“AR series routers support multiple deployment methods including CLI, DHCP Option 148, and web-based registration.”

Understanding VXLAN and BGP EVPN Control Plane

VXLAN (Virtual eXtensible LAN)is anoverlay network technologythat enablesLayer 2 (L2) extension over an IP-based networkusingMAC-in-UDP encapsulation.

????Traditional VXLAN Flooding Issue:

Without BGP EVPN, VXLAN usesflood-and-learnbehavior for MAC address learning.

Broadcast, Unknown Unicast, and Multicast (BUM) trafficis flooded to all VTEPs, which is inefficient.

????How Does BGP EVPN Solve Flooding?

BGP EVPN (Ethernet VPN) replaces the flood-and-learn model with a distributed control plane.

MAC/IP bindings are advertised through BGP EVPN Type 2 routes, eliminating the need forflooding ARP requests.

VXLAN routers learn MAC addressesproactivelyinstead of relying on flooding.

Why is the Answer TRUE?

✅BGP EVPN fully prevents ARP flooding by distributing MAC/IP bindings via control plane updates.

✅VTEPs only send traffic to known destinations, reducing network congestion.

✅BGP EVPN is the industry standard for large-scale data center and campus VXLAN deployments.

Real-World Application:

Data Centers:Avoids unnecessaryARP request floodingin large cloud networks.

Campus Networks:ReducesL2 broadcast storms, improving network efficiency.

Service Provider Networks:Enablesscalable multi-tenant VXLAN solutions.

✅Reference:Huawei HCIE-Datacom Guide – VXLAN BGP EVPN Control Plane Architecture

Comprehensive and Detailed In-Depth Explanation:

TheHuawei SD-WAN Solutioninvolves four types of channels to ensure smooth and efficient network operation:

Management Channel (A):Used for managing and monitoring SD-WAN devices. It facilitates communication between theiMaster NCE-Campus controllerand SD-WAN devices.

Control Channel (B):Responsible for transmittingcontrol plane informationsuch as routing updates and protocol control messages.

Data Channel (C):Carries actualuser data trafficover the SD-WAN network.

Orchestration Channel (D):Used forservice orchestration, configuration delivery, and policy management.

All four channels work together to provide comprehensive network management, data transmission, and service orchestration in an SD-WAN environment.

InMPLS VPN, packets are forwarded usingtwo labels:

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

Inner label (VPN Label)– Used by theegress PEto 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.

Theinner label is assigned by the egress PEand 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 thesecond-to-last router(P router) removes the outer MPLS label before forwarding to theegress PE.

This reduces theprocessing overheadon the egress PE.

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

Theouter label is used to forward the packet across the MPLS backbone.

Before reaching the egress PE, thepenultimate router still has the outer labeland processes it.

Incorrect Option:

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

This isincorrectbecause theinner label (VPN label) is still presentwhen the packet reaches the egress PE.

Only theouter labelis 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

The incorrect statement is Option C, which says “A site can only belong to only one VPN.” This is false because a single site can belong to multiple VPNs if needed. For example, in some enterprise designs, a site may be part of both the Finance VPN and the Management VPN by configuring multiple routing instances (VRFs) and policies accordingly.

Exact Extract - HCIE-Datacom VPN Technologies Chapter:

“A site may be associated with one or more VPNs, depending on business requirements. This is achieved through VRF and route-target configurations.”

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

Mismatched Area Addr(L1): 13

This clearly indicates that thearea addresses are different, which prevents theLevel-1 adjacencyfrom forming.

Why is Option D Correct?

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

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

If R3 and R4 wereLevel-2 routers, they could form an adjacencyeven 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 isD.

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

Comprehensive and Detailed In-Depth Explanation:

In BGP EVPN,Type 2routes (MAC/IP Advertisement routes) are used to advertise:

MAC addressesof endpoints.

ARP entries(MAC-to-IP bindings).

IRB (Integrated Routing and Bridging) routes, allowing the advertisement of both Layer 2 and Layer 3 reachability.

These routes are essential for enabling dynamic VXLAN tunnel establishment and seamless host mobility.

Type 1 (Ethernet Auto-Discovery):Used for multi-homing information.

Type 3 (Inclusive Multicast Ethernet Tag):Used for BUM (Broadcast, Unknown unicast, and Multicast) traffic.

Type 4 (Ethernet Segment):Used for identifying Ethernet segments in multi-homing scenarios.

InSR-MPLS (Segment Routing over MPLS),prefix SID conflictsmay occur if multiple prefixes are assigned the same SID or vice versa.

Conflict resolution principle (Huawei standard):

When there aremultiple SIDs for the same prefix, theSID with the lowest value wins.

Whenthe same SID is assigned to multiple prefixes, theprefix with the smallest addresswins.

Apply to this case:

Conflict: Two entries for1.1.1.1/32withSID 2 and SID 1.

SID 1 is lower, so1.1.1.1/32 → SID 1is selected.

Correct answer: D. 1.1.1.1/32 → SID 1

Comprehensive and Detailed In-Depth Explanation:

A. Correct:OPS can use themaintenance assistantto triggerPython scriptsperiodically or based on events.

B. Correct:OPS supportsautomatic deploymentusing Python scripts to download software and configuration files.

C. Incorrect:OPS doesnot inherently provide local storagefor temporarily saving execution results when the network is disconnected. This would require additional programming logic in the script itself, which is not a built-in feature of OPS.

D. Correct:OPS can run scripts toautomatically check device healthand report the status.

Therefore, the incorrect statement isC.

Forwarding Equivalence Class (FEC)is a key concept inMPLS (Multiprotocol Label Switching), where packets with thesame forwarding characteristicsare grouped into an FEC and assigned a label.

Correct Answers (Cannot be Used for FEC Allocation):

A. Fragment Offset–Incorrect as an FEC allocation standard

Fragment offset is used forreassembling fragmented IP packetsat the receiver side.

It isnot relevant for MPLS label assignment.

B. Application Protocol–Incorrect as an FEC allocation standard

MPLSdoes not classify packets based on application-layer protocols(e.g., HTTP, FTP).

It worksmainly at Layer 2 and Layer 3.

Incorrect Answers (Valid FEC Allocation Standards):

C. Destination Address–Valid FEC allocation criterion

One of themost commonMPLS FEC classifications.

Packets with thesame destination are groupedinto the same FEC.

D. Class of Service (CoS)–Valid FEC allocation criterion

MPLS usesCoS-based traffic classification(e.g., Exp bits in MPLS headers).

Different CoS levels can be mapped to different labels.

Reference from Huawei HCIE-Datacom Documentation:

Huawei MPLS Technology Guide – FEC and Label Assignment

HCIE-Datacom MPLS VPN Configuration Guide

Comprehensive and Detailed In-Depth Explanation:

The statementAis incorrect because enablingDHCP snooping in the VLAN viewonly takes effect on interfaces within that specific VLAN that have DHCP snooping configured. It doesnot automatically apply to all interfaces of the device. Each interface within the VLAN must individually be configured or marked as trusted/untrusted.

B:Correct, as DHCP snooping, when enabled globally without any additional specifications, defaults to processingDHCPv4messages.

C:Correct, as DHCP snooping can protect against DHCP spoofing attacks by marking interfaces astrustedoruntrusted.

D:Correct, enabling DHCP snooping on an interface means it will monitor all DHCP messages on that specific interface.

OSPFv3 Configuration Principles:

OSPFv3, the OSPF version supporting IPv6, differs from OSPFv2 in several aspects:

Interface-based Configuration:

OSPFv3 is configured on interfaces directly, unlike OSPFv2 which uses the network command.

Router ID:

The Router ID is still a 32-bit number, typically represented as an IPv4 address.

It must be explicitly specified since OSPFv3 requires a Router ID for operation, even though it supports IPv6.

Analysis:

A. [R1-GigabitEthernet0/0/1] ospfv3 1 area 0:

Correct. This command enables OSPFv3 process 1 on the GE0/0/1 interface in Area 0.

B. [R1-ospfv3-1] router-id 10.1.1.1:

Correct. This correctly sets the Router ID for OSPFv3 process 1.

C. [R1-ospfv3-1-area-0.0.0.0] network 2001:DB8:2345:12::1 ::

Incorrect. OSPFv3 does not use the network command as in OSPFv2. Instead, OSPFv3 is directly configured on interfaces.

D. [R1] router id 10.1.1.1:

Incorrect. The Router ID should be set within the OSPFv3 process view, not the global configuration view.

Therefore, the correct answers are A and B.

Understanding SR-MPLS TE (Segment Routing MPLS Traffic Engineering)

????What is SR-MPLS TE?

Segment Routing (SR) replaces traditional MPLS LDP/RSVP-TE signaling.

UsesSR-TE policiesto define network pathswithout requiring per-flow state on intermediate routers.

????How is the SR-MPLS TE Path Calculated?

✅By the SDN Controller (Centralized Path Computation)

The controller (e.g.,Huawei iMaster NCE) calculates theoptimal SR pathbased on:

Bandwidth requirements

Latency constraints

Traffic policies

The controllerthen delivers the SR policy to the ingress router.

✅By the Ingress Router (Distributed Path Computation)

Theingress routercomputes theSR path dynamicallybased onlocal constraints.

This method is usefulwhen no centralized controller is available.

Why is the Answer TRUE?

✅Both centralized (controller-based) and distributed (ingress router-based) path computation are supported in SR-MPLS TE.

Real-World Application:

5G and Cloud WANs:Centralized path optimizationreduces congestion dynamically.

Enterprise Networks:Local path computation ensuresfast rerouting in case of failures.

✅Reference:Huawei HCIE-Datacom Guide – SR-MPLS TE and Path Computation Methods

SSH (Secure Shell) is a protocol designed for secure remote access and is always built on TCP, typically on port 22. UDP is not supported for SSH, as it is connectionless and doesn't provide the required reliability and order.

Exact Extract – Huawei Security Protocol Fundamentals:

“SSH is a TCP-based protocol. It does not support UDP. TCP ensures session reliability and data integrity, which are critical for SSH.”

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

6PE (IPv6 over MPLS without VPNs):

Uses global IPv6 routingover MPLS.

No VPN instances (VRFs) are created on PEs.

IPv6 addresses cannot be reusedacross 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 PEsto separate customer networks.

IPv6 addresses of CEs can be reusedin 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.

Sinceeach VPN instance (VRF) maintains its own IPv6 routing table, IPv6 addresses of CEscan be reused across different VPNs.

Incorrect Answer Explanations:

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

Wrong!6PEdoes 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 asingle IPv6 global routing table, IPv6 addressescannot be reused.

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

Wrong!6VPErequires VPN instances (VRFs) on PEsto 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

InMPLS LDP (Label Distribution Protocol), label retention modes control how labels are stored in theLabel Forwarding Information Base (LFIB).

DU Label Advertisement Mode (Downstream Unsolicited):

Labels areadvertised to all LDP peers without a request.

The receiving routerdecides which label to usefor forwarding.

Liberal vs. Conservative Label Retention:

✅Liberal Label Retention Mode (Correct Answer)

All received labels from all LDP peers are stored.

Even if apeer is not the optimal next hop, its label is retained.

Allowsfaster convergenceduring failures.

❌Conservative Label Retention Mode

Only the label from the best next-hop peer is stored.

Reduces memory usage but can slow down convergence in case of failure.

Reference from Huawei HCIE-Datacom Documentation:

Huawei MPLS LDP Configuration Guide – Liberal vs. Conservative Label Retention

HCIE-Datacom Training Material – Label Advertisement in MPLS Networks

EVPN Route Types:

Type 1 (MAC/IP Advertisement Route):Advertises host MAC and IP information —used.

Type 2 (MAC/IP Advertisement Route):Advertises MAC + IP binding for end hosts —used.

Type 3 (Inclusive Multicast Ethernet Tag Route):Used to advertise VXLAN multicast group info —used.

Type 4 (Ethernet Segment Route):Used inmulti-homing scenarios, especially inDC (data center) environments, to coordinate DF election —typically not used in campus VXLAN.

So incampus virtualized networks, which are oftensingle-homed,Type 4 is not required.

Correct answer: C. Type 4

Understanding Telemetry Encoding Formats

????What is Telemetry?

Telemetry is a real-time network monitoring methodthat provideshigh-frequency data collection.

Used inAI-driven networks for predictive analytics and automation.

????Common Telemetry Encoding Formats:

✅GPB (Google Protocol Buffers)

Highly efficient binary formatthat reducesmessage size and CPU overhead.

Commonly used forhigh-speed, real-time analytics.

✅JSON (JavaScript Object Notation)

Human-readable format, widely used inRESTful APIs.

Less efficientthan GPB in high-speed telemetry buteasier 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:UsesGPB for fast data collectionandJSON for API-based telemetry visualization.

AI-Driven Networks:High-speedAI analyticsleverageGPB encodingfor efficiency.

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

Comprehensive and Detailed Explanation:

TheHuawei Registration Query Centerallows devices to register and go online automatically in acloud-managed environment.

✔Supported Devices:

Switches✅

Access Routers (AR)✅

Access Points (APs)✅

Firewalls✅

✔How It Works:

Devices obtain theirregistration informationviaDHCP Option 148orpre-configured credentials.

The devices thenconnect to the registration query centerto retrieve configuration and authentication details.

Once authenticated, they goonline and become manageable via iMaster NCE-Campus.

????Reference:Huawei HCIE Datacom – CloudCampus Device Registration

Comprehensive and Detailed In-Depth Explanation:

WhenIS-ISis used as theIGP (Interior Gateway Protocol)to advertiseSegment Routing (SR) SIDs, theLevel-2 (L2) routeradvertisesnode SIDs globally across the entire IS-IS domain, not just within a single area.

Level-1 (L1) routersonly advertise within the local area, butL2 routersdistribute information across multiple areas, enabling inter-area reachability.

Therefore, the statement isFALSE.

In hot standby (active-active/load balancing) scenarios, Quick Session Backup is critical. This function ensures that session entries are immediately synchronized between firewalls to handle asymmetric traffic (where return traffic goes through a different firewall than the forward traffic).

Without it, the return packet may be dropped due to missing session information on the alternate firewall.

Exact Extract - HCIE-Datacom Security Module:

“When VGMP is in load balancing mode, quick session backup must be enabled to prevent traffic loss due to inconsistent forward and return paths.”

Comprehensive and Detailed Explanation:

✔BIER vs. PIM Multicast Routing:

BIER (Bit Index Explicit Replication)eliminates the need formulticast distribution trees (MDTs)by encodingreceiver information into the packet header.

PIM (Protocol Independent Multicast)requiresMDTs to manage multicast forwarding paths.

✔Correct Statements:

✅(A) BIER uses a Bitstring fieldin packet headers for forwarding.

✅(B) PIM builds MDTsto define multicast paths.

✅(C) BIER does NOT require MDTs, making it more scalable.

❌(D) Incorrect→ BIER does not require hop-by-hop join messages.

????Reference:Huawei HCIE Datacom – BIER and PIM Comparison

The command port-isolate enable is used on Huawei switches to completely isolate traffic at both Layer 2 and Layer 3 between different interfaces within the same VLAN. This isolation prevents any communication between isolated ports—even if they belong to the same subnet or VLAN—making it a critical security feature in multi-tenant environments.

Usage Context:

Often used in shared service or hotel network scenarios.

Can be applied in access port configurations.

Does not require additional VLAN creation or private VLAN features.

Huawei Datacom Reference:

"To completely isolate Layer 2 and Layer 3 communication between interfaces in the same VLAN, run the port-isolate enable command under the interface view."

(Source: HCIE-Datacom Study Guide V3.0 – Chapter: VLAN & Security Technologies, Section: Port Isolation)

SR-MPLS leverages IGP (OSPF/IS-IS) extensions to advertise Segment IDs (SIDs) and can also integrate with TE (Traffic Engineering) for bandwidth reservation using RSVP-TE or SR-TE.

Exact Extract – Huawei SR-MPLS Configuration Guide:

“SR-MPLS uses extensions in IGP to distribute label bindings and, combined with traffic engineering, supports bandwidth assurance and high-bandwidth services.”

Understanding the Telemetry Output:

Dest-addr: 192.168.56.1→The destination IP address is 192.168.56.1.✅

Dest-name: Dest1→The destination group name is Dest1.✅

Protocol: gRPC→Data push uses the gRPC protocol.✅

Vpn-name: - (empty)→No VPN encapsulation is used.❌

Incorrect Answer Explanation:

❌C. "VPN encapsulation is used for data push"→Incorrect!

The Vpn-name field isempty, indicating thatVPN encapsulation is NOT enabled for telemetry data transport.

Reference from Huawei HCIE-Datacom Documentation:

Huawei Telemetry Configuration Guide – Destination and Data Push Methods

HCIE-Datacom Study Material – gRPC and Telemetry Data Streaming

In Huawei’s CloudCampus Solution, when static IPsec VPN is used for WAN interconnection, the following devices are capable of acting as egress gateways for encrypted tunnels:

Access Point (AP)

Router

Switch

This is based on Huawei’s CloudCampus architecture, where all three device types can support VPN tunnel termination depending on the deployment size and use case.

Huawei Datacom Reference:

"In static IPsec VPN networking scenarios, egress devices can be APs, Routers, or Switches depending on the deployment model. This allows flexibility for small, medium, and large-scale branches."

(Source: HCIE-Datacom V1.0 Training Guide – WAN Interconnection and VPN Chapter)

Segment Routing over IPv6 (SRv6) defines several headend behaviors for how SRH (Segment Routing Headers) are added:

B. H.Insert — Inserts an SRH into an existing IPv6 packet.

C. H.Encaps — Encapsulates the original packet in a new IPv6 packet with an SRH.

D. H.Insert.Red — Performs insert behavior and reduces the payload for optimization.

A. H.Encaps.Red is not a defined SRv6 behavior — it’s an invalid option.

Exact Extract - Huawei SRv6 White Paper:

“H.Insert, H.Insert.Red, and H.Encaps are valid behaviors for injecting SRH. H.Encaps.Red is not defined in the SRv6 headend behavior set.”

To configure an SR-MPLS TE tunnel based on OSPF, all four options are mandatory:

A. Configure the LSR ID – LSR ID is required as the unique identifier of the router in MPLS and TE.

B. Enable segment routing in the OSPF process view – Needed to advertise segment information (SID).

C. Enable the opaque capability – Opaque LSAs are used to carry SR and TE information in OSPF.

D. Enable MPLS TE in the OSPF process view – Ensures that TE-related attributes (e.g., bandwidth) are advertised in OSPF LSAs.

Exact Extract - Huawei HCIE-Datacom SR-MPLS TE Configuration Guide:

“To support SR-MPLS TE over OSPF, it is necessary to configure the LSR ID, enable SR and MPLS TE capabilities in OSPF, and activate the OSPF opaque capability for carrying TE and SR attributes.”

Comprehensive and Detailed Explanation:

✔Inter-VN communicationallows users indifferent VNs (R&D and Marketing)to communicate.

✔Correct Steps:

✅(B) Deploy a Policy Control Matrix→ Definesrules for inter-VN communicationbetween security groups.

✅(C) Configure Inter-VN Communication→ Enablesrouting between VNsthrough theborder gateway or firewall.

✔Why Not Other Options?

❌(A) Deploy Network Service Resources→ This is forinternal VN service deployment, not inter-VN communication.

❌(D) Deploy an External Network→ This is forInternet or WAN access, not internal VN-to-VN communication.

????Reference:Huawei HCIE Datacom – Virtual Network Intercommunication

????Analyze the Configuration:

[R2] acl 2000

[R2-acl-basic-2000] rule deny

[R2] ospf

[R2-ospf-1] area 1

[R2-ospf-1-area-0.0.0.1] filter 2000 import

[R2-ospf-1-area-0.0.0.1] quit

[R2-ospf-1] default-route-advertise always

????Understanding Key Concepts:

Type 3 LSAs (Inter-Area Routes):

Generated by ABRs to advertisesummary routesbetween areas.

Filtering Type 3 LSAsis possible using import filters (like in Area 1).

Type 5 LSAs (External Routes):

Flooded only within the same ASbutdo not enter stub or NSSA areas.

✅Breakdown of the Options:

A. Type 5 LSAs are flooded in Area 1→❌Incorrect

If Area 1 is astub or NSSA, thenType 5 LSAs are not allowed.

Although the diagram does not explicitly say Area 1 is a stub/NSSA,real deployments often use stub areas at the edge (like Area 1).

More importantly,the filter is applied to Area 1, and there isno redistributionof external routes into Area 1 in the config.

Therefore, Type 5 LSAs wouldnot be floodedthere.

B. Type 3 LSAs are not flooded in Area 1→✅Correct

The command filter 2000 import with ACL rule deny meansType 3 LSAs are filtered from Area 0 into Area 1.

C. Type 3 LSAs are not flooded in Area 2→✅Correct

There isno filter applied to Area 2, so thiscould be false,butsince the question asks for the incorrect statement, this is not the answer.

D. Type 5 LSAs are flooded in Area 2→✅Correct

Area 2 is not shown to be stub or NSSA, and there’s no filter or restriction configured.

Hence,Type 5 LSAs are allowedandflooded in Area 2.

✅Correct Answer: A. Type 5 LSAs are flooded in Area 1.

OSPFv3 (used for IPv6) usesIPv6 multicast addressesfor communication between routers:

FF02::5— All OSPF routers.

FF02::6— All OSPF Designated Routers (DRs) and Backup Designated Routers (BDRs).

FF08::x— These are used for organization-local scope, which isnotapplicable to standard OSPFv3 operation.

Therefore:

C. All OSPF routers use FF02::5— Correct

D. The DR uses FF02::6— Correct

A and B (FF08::x)— Incorrect. These addresses are not used by OSPFv3 in this context.

Correct answers: C and D

This statement confuses congestion management with congestion avoidance:

Congestion Management: Refers to techniques like PQ, CQ, WRR, etc., to schedule packets in queues — i.e., manage how packets are sent, not discarded.

Congestion Avoidance: Techniques like WRED are used to preemptively discard packets to avoid full queues — these do discard packets.

Hence, congestion management does NOT discard packets — it's about controlling transmission order and prioritization.

Correct answer: B. FALSE

Huawei’sSD-WAN solutionoffers a full suite of application optimization technologies, including:

Application identification: Uses DPI and traffic signatures to identify applications.

Intelligent traffic steering: Dynamically routes traffic based on application type and real-time link performance.

WAN optimization: Reduces latency, deduplicates traffic, and optimizes throughput for key apps.

QoS: Prioritizes critical applications and ensures bandwidth guarantees.

All listed options are part of the Huawei SD-WAN solutionfor optimizing user experience and application performance.

Correct answers: A, B, C, D

Comprehensive and Detailed In-Depth Explanation:

In VXLAN encapsulation, the data frame is encapsulated as follows:

Original Ethernet Frame:The data packet to be encapsulated.

VXLAN Header:Contains the VXLAN Network Identifier (VNI) and other information.

UDP Header:VXLAN usesUDP (User Datagram Protocol)to transport the encapsulated data over an IP network.

Outer IP Header:Provides the source and destination IP addresses of the VTEPs.

Therefore, theUDP header(C) isencapsulated between the outer IP header and the VXLAN header.

Comprehensive and Detailed Explanation:

IP Source Guard (IPSG)is aLayer 3 security featureused to protect againstIP address spoofingby filtering packets based onbound IP-MAC mappings.

Correct Statements:✔IPSG is a Layer 3 filtering mechanismthat checks if the source IP address of a packet matches thelearned or configuredbindings (Option B).✔IPSG prevents unauthorized IP address changesby enforcing binding rules (Option C).✔IPSG defends against IP spoofing attacksby dropping packets fromunauthorized sources(Option D).

Incorrect Statement:❌Option A is incorrectbecause IPSGdoes not send alarms to an NMSwhen an invalid packet is detected. Instead, itdropsthe packet.

Thus, the correct answer isA.

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

Comprehensive and Detailed In-Depth Explanation:

InNETCONF (Network Configuration Protocol), the operation can includeoperation attributesto 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)isnot a valid NETCONF operation attribute.

Dis the correct answer as it does not exist within theNETCONF operation attribute set.

Node segments in SR-MPLS (Segment Routing over MPLS) are typically automatically generated and distributed via IGP protocols (such as IS-IS or OSPF) using SR extensions. There is no need to manually configure node segments on every router.

Exact Extract – Huawei HCIE-Datacom Study Guide – Segment Routing:

“Node SIDs are automatically generated and advertised by IGPs with SR extensions. Manual configuration is not required except in special cases like adjacency SIDs.”

IS-IS was originally designed for IPv4, but extensions via TLVs (Type-Length-Value) allow it to support IPv6. These are referred to as New IS-IS TLVs, including TLV 236 (IPv6 Reachability), TLV 232 (IPv6 Interface Address), etc. These TLVs are crucial for IPv6 route computation within IS-IS.

Exact Extract - HCIE-Datacom Guide – IPv6 Routing Protocols Chapter

“IS-IS uses new TLVs such as TLV 236 and TLV 232 to carry IPv6 prefix and interface address information. These TLVs are essential to enable IPv6 route calculation.”

Understanding User Authentication Points in a Network

Authentication pointscan be deployed at different network layersbased on security and scalability needs:

✅Access Layer Authentication:

Ensureshigh security & granular control(user-level authentication).

Preferred inhigh-security enterprise networks.

✅Aggregation or Core Layer Authentication:

Reduces authentication overheadbutprovides less granular control.

Suitable forlarge-scale networkswhere 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:Providesfine-grained control per userand 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 meanless 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 isbest applied at the access layerforgranular 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 worksat both layers, butpolicy adjustmentsmay be needed.

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

Comprehensive and Detailed In-Depth Explanation:

When configuring avirtualized campus networkoniMaster NCE-Campus, the platform supports automatic delivery of routing policies when connecting to external networks, including the Internet.

This feature ensures that traffic destined for external networks isautomatically directed to the appropriate egress points.

TheNCE-Campusautomatically creates and delivers thedefault routeor specific routes, depending on the network topology and configuration.

This simplifies network management by eliminating the need for manual route configuration on each device.

Therefore, the statement isTRUE.

Comprehensive and Detailed Explanation:

✔Huawei OPS (Open Programmability System)followsRESTful API principles, usingHTTP methodsfor device management.

✔HTTP Methods Used in OPS:

✅GET→ Retrieves data from the device.

✅POST→ Creates new data/configurations.

✅PUT→ Replacesentire configuration objects.

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

SincePATCH is used for modifying specific values in managed objects, the correct answer isD.

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

The command output shows:

*>i before both networks, which means these routes are the preferred routes (*) and are learned via internal BGP (i).

Two networks are listed: 3002::3 and 3002::4, which means R1does havethese two routes in its BGP IPv6 routing table.

For 3002::4, the path origin shows 65001 i, which means this route originated from AS 65001 and was learned through IBGP.

The AS Path attribute is only shown for 3002::4, but both routes are clearly present.

Therefore, the correct conclusion is:

D. R1 has routes 3002::3/128 and 3002::4/128.

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.”

Understanding VXLAN and NVE Interfaces

VXLAN (Virtual Extensible LAN)allows forLayer 2 network extensionoverLayer 3 infrastructure.

????Key VXLAN Components:

NVE (Network Virtualization Edge) Interface→ VXLAN tunnels are created usingone or more NVE interfaces.

BD (Bridge Domain)→ Logical grouping of VXLAN traffic.

VNI (VXLAN Network Identifier)→ 24-bit unique ID for traffic segmentation.

????Analysis of Each Option:

✅A. One NVE interface can be used for multiple VXLAN tunnels if ingress replication is used.

Correct:VXLAN tunnels can be dynamically learned usingBGP EVPN, meaning multiple tunnels can use the sameNVE interface.

✅B. An NVE interface can be associated with multiple VNIs, allowing multiple BDs on one NVE.

Correct:Each NVE interface can carrymultiple VNIs, reducing the need for separate interfaces.

❌C. One NVE interface must be created per VXLAN tunnel.

Incorrect:Multiple VXLAN tunnelscan share a single NVE interface.

❌D. One NVE must be created for each BD.

Incorrect:One NVE can support multiple BDs.

????Real-World Application:

Cloud Data Centers:VXLAN enablesmulti-tenant network segmentation.

Campus Networks:SimplifiesLayer 2/Layer 3 connectivityacross sites.

✅Reference:Huawei HCIE-Datacom Guide – VXLAN and NVE Configuration

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.

A white background with black lines AI-generated content may be incorrect.

???? R1 – Headend

It receives a normal IPv6 packet from CE1.

It inserts the SRH (Segment Routing Header) with segment list.

Therefore, R1 is the Headend.

Huawei Reference:

“The SRv6 headend node receives a normal IPv6 packet and inserts an SRH, becoming the source of the SR path.”

(Source: HCIE-Datacom V1.0 – SRv6 Fundamentals)

???? R2 – Transit Node

R2 simply forwards the SRv6-encapsulated packet.

It does not process any segment SID.

Hence, R2 is a Transit node.

“Transit nodes in SRv6 just forward packets based on the active segment in the IPv6 destination address without processing SRH.”

(Source: HCIE-Datacom Study Guide – SRv6 Node Roles)

???? R3 – Endpoint

The first SID in SRH is FC03::3, which belongs to R3.

R3 processes the SID, pops it, and forwards the packet to the next segment FC04::4.

Thus, R3 is an Endpoint for one segment.

???? R4 – Endpoint

The final destination SID in the SRH is FC04::4, which belongs to R4.

R4 performs the final End behavior, handling the payload.

So, R4 is also an Endpoint.

Comprehensive and Detailed In-Depth Explanation:

The diagram shows aWAN networkwhereSegment Routing (SR)is used in conjunction with theiMaster NCEcontroller. The network consists ofData Centers (DCs),Branches,Provider Edge (PE)routers, andRoute Reflectors (RR)withinAS 65600. Let's analyze each network technology and its placement in the scenario.

1. BGP-LS (Border Gateway Protocol - Link State):

Application Location:1 (PE to RR)

BGP-LS is used tocollect and distribute network topology informationfrom theIGP (Interior Gateway Protocol)domain.

It enables theiMaster NCE(controller) to learn about the network topology and SR information from PE routers.

The PE routers send theirlink-state informationto theRRusingBGP-LS.

Why Location 1:

The RR collects topology data from PEs and forwards it to the controller for path computation.

2. BGP (Border Gateway Protocol):

Application Location:2 (RR to iMaster NCE)

Standard BGP is used forroute distributionandnetwork connectivity.

The RR usesBGPto exchange route information with thecontroller(iMaster NCE).

Why Location 2:

TheRRaggregates routes and exchanges them with the iMaster NCE for centralized management.

3. MP-IBGP (Multiprotocol Internal BGP):

Application Location:3 (PE to PE)

MP-IBGP is used toexchange VPNv4 and VPNv6 routesbetween PE routers within thesame AS.

It allows PEs toadvertise VPN routesacross thebackbone network.

Why Location 3:

PEs need to communicate VPN-related information within the AS, ensuring end-to-end connectivity between DCs and branches.

4. BGP SR-Policy/PCEP (Path Computation Element Protocol):

Application Location:4 (iMaster NCE to PE)

BGP SR-Policy andPCEPare used by thecontrollertodistribute SR policiesto the PE routers.

TheiMaster NCEcalculates optimal paths and sends the SR policies to PEs viaBGP SR-PolicyorPCEP.

Why Location 4:

The controller programs theSegment Routing pathsdirectly to the PEs for optimal traffic engineering.

Why This Mapping Is Correct:

The mapping is based on theroles and functions of each protocolwithin theSR-based WAN architecture. The controller uses BGP-LS to learn topology, BGP for route reflection, MP-IBGP for VPN route exchange, and BGP SR-Policy/PCEP for path computation and distribution.