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

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.

Dynamic VLAN Authorization in Huawei CloudCampus

Dynamic VLAN assignmentallows users to be placed into specific VLANsbased on authentication methods, ensuring security and network segmentation.

Correct Explanations:

✅A. Wired users using 802.1X authentication receive VLAN assignments dynamically.

After authentication,the access control system (e.g., iMaster NCE-Campus)assigns VLANs dynamically.

✅C. Wireless users using 802.1X authentication also receive VLAN assignments.

Similar to wired users,wireless 802.1X authentication allows dynamic VLAN assignmentvia the RADIUS server.

✅D. Wired users using MAC authentication can receive VLAN assignments.

If a userdoes not support 802.1X, MAC authentication can still be used to assign VLANs dynamically.

Incorrect Statement Explanation:

❌B. When wireless users pass Portal authentication, they join the authorization VLANs delivered to edge nodes.

Wrong!InPortal authentication, VLAN assignmentis not dynamically deliveredbecausePortal authentication typically applies access policies, not VLAN changes.

Dynamic VLAN assignment is mainly used with 802.1X or MAC authentication.

Reference from Huawei HCIE-Datacom Documentation:

Huawei CloudCampus Configuration Guide – Dynamic VLAN Assignment and Authentication

HCIE-Datacom Training Material – VLAN Authorization in Virtualized Campus Networks

MPLS Positioning in the TCP/IP Model

MPLS (Multiprotocol Label Switching) operatesbetween the Data Link Layer (Layer 2) and the Network Layer (Layer 3).

✅MPLS is protocol-independentand supports variousnetwork layer protocols (IPv4, IPv6, VPN, etc.)by using labels instead of traditional IP routing.

✅How MPLS Works:

MPLSassigns labels to packets, allowing fast forwarding based on the label rather than a routing table lookup.

SupportsLayer 3 VPNs (L3VPNs), Layer 2 VPNs (L2VPNs), and MPLS Traffic Engineering (MPLS-TE).

✅Why MPLS is Between Layer 2 and Layer 3?

MPLS adds a label between the Layer 2 (Ethernet, PPP) and Layer 3 (IP) headers, effectivelycreating a separate forwarding mechanism.

Label Switching Routers (LSRs) forward packets based on labels instead of IP addresses, reducing processing time.

Reference from Huawei HCIE-Datacom Documentation:

Huawei MPLS Technology Guide – MPLS Architecture and Label Switching

HCIE-Datacom Study Material – MPLS Positioning and Functionality in TCP/IP