Pass the Huawei HCIE-Datacom H12-891_V1.0 Questions and answers with ExamsMirror

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

In BGP, community attributes help control the advertisement scope of BGP routes. Here’s what each option means:

No_Export: This well-known community attribute prevents BGP routes from being advertised to external BGP (EBGP) peers. Routes with this attribute can still be advertised to internal BGP (IBGP) peers within the same AS. This ensures that the route remains within the originating AS.

No_Advertise: This attribute means that the route should not be advertised to any BGP peer, whether internal or external.

Internet: Indicates that the route can be advertised to all BGP peers, both internal and external, with no restrictions.

No_Export_Subconfed: Similar to No_Export, but it also restricts advertisement to peers within a BGP confederation. It ' s more specific and not generally used just to keep routes inside one AS.

Therefore, the correct answer is B. No_Export, as it is the attribute that ensures BGP routes remain within the AS by not being sent to EBGP peers.

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 is empty, indicating that VPN 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

Comprehensive and Detailed In-Depth Explanation:

1. Understanding SR-MPLS (Segment Routing with MPLS):

Segment Routing (SR) leverages MPLS labels to define paths through the network.

The labels represent segments (nodes or specific paths) rather than traditional LDP or RSVP-TE labels.

The label stack determines the forwarding path through the network.

Top Label: Determines the next hop.

Next Label: After label pop, it indicates the subsequent hop.

2. Analyzing the Given Label Stack:

The label stack encapsulated by R1 is as follows:

Layer2: 2046

2013

2032

2024

2046

Layer3

The top label (2046) indicates that the next-hop router is R4.

After R4 pops the top label, the next label (2046) directs the packet to R6.

3. Forwarding Path Analysis:

Step 1: R1 sends the packet to R2 based on internal routing.

Step 2: R2 forwards the packet directly to R4 as dictated by the top label (2046).

Step 3: R4 pops the top label (2046) and checks the next label (again 2046), directing the packet to R6.

Step 4: R6 receives the packet as the final destination.

4. Why Option B is Correct:

The path R1-R2-R4-R6 matches the label stack processing in SR-MPLS.

The labels indicate the shortest path chosen by SR policies, which is R1 → R2 → R4 → R6.

The SR-MPLS label stack efficiently guides the packet through the optimal path without complex signaling.

Why Other Options Are Incorrect:

Option A (R1-R2-R3-R5-R6):

This path does not match the label sequence as the labels clearly indicate a direct path via R4, not through R3 and R5.

Option C (R1-R3-R2-R4-R6):

This path is longer and unnecessary, as the label stack indicates a more direct path via R2 and R4.

In BGP/MPLS IP VPN, when OSPF is used as the PE-CE routing protocol, Domain IDs are used to determine whether the OSPF routes imported into the VPN instance belong to the same OSPF domain.

How Domain ID Works in OSPF and MPLS VPN:

Same Domain ID (OSPF Intra-domain routes)

If the PE router ' s Domain ID matches the OSPF Domain ID, routes are treated as intra-area routes.

The routes retain OSPF attributes when redistributed into the VPN.

Different Domain ID (OSPF Inter-domain routes)

If the Domain ID does not match, routes are treated as external routes (Type 3 or Type 5 LSAs).

The PE router redistributes these routes as OSPF external routes.

Example Huawei Configuration for Domain ID in OSPF VPN:

ospf 1 vpn-instance VPN1

domain-id 1.1.1.1

This ensures consistent OSPF route types when exchanging routes between PE and CE.

Reference from Huawei HCIE-Datacom Documentation:

Huawei MPLS VPN Configuration Guide – OSPF Domain ID in PE-CE Routing

HCIE-Datacom Study Material – OSPF & MPLS VPN Route Redistribution

Comprehensive and Detailed In-Depth Explanation:

The correct configuration is qos car inbound cir 50000 pir 100000.

CIR (Committed Information Rate): The guaranteed minimum bandwidth, set to 50 Mbit/s (50000 kbps).

PIR (Peak Information Rate): The maximum allowable bandwidth, set to 100 Mbit/s (100000 kbps).

This configuration ensures that during peak hours, the minimum guaranteed bandwidth is 50 Mbit/s, while during off-peak hours, the bandwidth can increase to a maximum of 100 Mbit/s. The settings align with the carrier ' s requirements for dynamic bandwidth allocation based on network load.

GRE (Generic Routing Encapsulation) has the following benefits:

B. VPN Construction — GRE is often used to build site-to-site VPNs.

C. ARP Encapsulation — GRE supports Layer 2 protocol encapsulation such as ARP.

D. Multicast Support — GRE tunnels can encapsulate multicast packets, unlike traditional IPsec.

A. Enlarging the hop limit is incorrect — GRE does not inherently change TTL or hop behavior; routing protocols still use standard IP processing.

Exact Extract - Huawei HCIE-Datacom Tunneling Chapter:

“GRE can encapsulate multicast and broadcast packets and supports L2 protocols like ARP. It is often used for VPN construction over the internet.”

Huawei iMaster NCE-Campus provides open APIs for seamless integration with third-party applications and services. Each API serves a specific purpose in managing network security, operations, analytics, and user interactions.

1. Authentication and authorization → Third-party authentication API

This API is used to integrate third-party authentication systems, such as:

LDAP (Lightweight Directory Access Protocol)

RADIUS (Remote Authentication Dial-In User Service)

OAuth/OpenID authentication

It ensures secure user identity verification, access control, and single sign-on (SSO) in CloudCampus networks.

2. Network O & M → Infrastructure API

The Infrastructure API provides tools for network monitoring, diagnostics, and automated management.

It is used for:

Device status monitoring

Network topology visualization

Fault detection and real-time alerts

Performance optimization

3. LBS (Location-Based Services) → LBS API

The LBS API enables applications to access location data collected by the network.

It is used for:

Tracking users or assets within a campus network

Heatmap generation and movement analytics

Geo-fencing and location-based policies

4. Crowd profiling → VAS API

VAS (Value-Added Services) API is designed for advanced analytics and business intelligence.

It supports:

User behavior analytics

Demographic profiling

Marketing strategies based on network usage patterns

Reference from Huawei HCIE-Datacom Documentation:

HCIE-Datacom Training Guide – CloudCampus Solution

Huawei iMaster NCE-Campus API Documentation

Huawei CloudCampus Solution Whitepaper – Open API and Use Cases

In Huawei’s VXLAN implementation, the typical mapping between VNIs (VXLAN Network Identifiers) and BDs (Bridge Domains) is:

1:1 mapping — each VNI is uniquely associated with a single bridge domain.

This allows proper MAC learning and forwarding in the data plane for isolated tenant traffic.

Other mappings (N:1, 1:N, N:M) may be technically possible but not recommended or supported in most enterprise deployments.

Correct answer: B. 1:1