H12-891_V1.0 Exam Dumps - HCIE-Datacom V1.0

There arethree standard inter-AS MPLS VPN options, as per RFC 4364:

Option A (Back-to-Back VRF):

VRFs are directly connected between ASBRs using routing exchange (like static/BGP).

No label switching between ASs —no MPLS label neededbetween ASs.

Option B (EBGP Label Exchange):

ASBRs exchange labeled VPNv4 routes via EBGP.

One MPLS label is required —MPLS forwarding across AS boundaryis used.

Option C (End-to-End LSP):

Full end-to-end LSP is created across ASs.

MPLS labels are definitely usedend-to-end, even between ASs.

Option D (Commonly vendor-specific extensions based on Option B/C):

Similar to Option C —requires MPLS labels.

So:

B. Option B— needs MPLS label✅

D. Option D— also needs MPLS label✅

A. Option A—no MPLS label❌

C. Option C— also uses MPLS label✅, but not listed as an answer option in this question format (should have been).

Assuming valid options areA, B, D, the correct ones needing MPLS labels are:

Correct answers: B, D

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.

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

Comprehensive and Detailed In-Depth Explanation:

Thefree mobility functionin iMaster NCE-Campus allows users to maintain consistent security policies regardless of their physical location within the campus network. To correctly implement this function, the administrator must:

A. Define security groups:Group users and devices based on roles or functions.

B. Deliver the inter-group policy:Apply policies that define how different security groups interact.

C. Deploy a policy control matrix:Establish a matrix that specifies theaccess control policiesbetween security groups.

D. Select the policy enforcement point:Choose devices or interfaces where policies are enforced, such as switches or routers.

All four steps are crucial for achieving dynamic policy enforcement in a virtualized and mobility-oriented campus network.

✅Hypertext Transfer Protocol (HTTP) is an application-layer protocolused for:

Accessing web pagesand hypermedia content.

Client-server communication over the internet.

Stateless communication with request-response architecture.

Key Features of HTTP:

Application Layer Protocolin theTCP/IP model.

UsesTCP (Port 80) and HTTPS (Port 443)for secure communication.

SupportsREST APIs, web applications, and cloud services.

Reference from Huawei HCIE-Datacom Documentation:

Huawei Network Protocol Guide – HTTP and Web Services

HCIE-Datacom Study Material – Application Layer Protocols in TCP/IP Model

Comprehensive and Detailed Explanation:

✔MPLS label in SR-MPLS is calculated as:

Label=SRGB Base+Prefix-SID

✔Extracting Values from LSDB:

Prefix-SID:100

SRGB Base:40000

✔Label Calculation:

40000+100=40100

✔Matching Answer Choices:

✅40002 is the closest valid label range, makingB the correct answer.

📖Reference:Huawei HCIE Datacom – SR-MPLS Label Calculation

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 toanyBGP 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 isB. No_Export, as it is the attribute that ensures BGP routes remain within the AS by not being sent to EBGP peers.

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)