HCIP-Datacom Changed H12-821_V1.0 Questions

By default, Huawei firewalls create security zones such as Trust, Untrust, and Local. The DMZ (Demilitarized Zone) is a security zone explicitly created by users. A DMZ is used to isolate an internal network from the external one, providing an additional layer of security by placing public-facing services (e.g., web servers) in this intermediary zone. This setup ensures that if a public-facing service is compromised, the internal network remains secure. Huawei Firewall configuration steps confirm this zoning principle, making DMZ creation an explicit user-driven action ​.

 OSPF Area Design and Loop Prevention :

OSPF uses a hierarchical structure with areas to improve scalability and efficiency. Area 0, the backbone area, plays a crucial role in ensuring loop-free route distribution between areas. The following mechanisms are key to preventing routing loops:

Strict adherence to hierarchical area design.

Prohibition of direct inter-area route exchanges between non-backbone areas.

GRE (Generic Routing Encapsulation) is not a Layer 2 VPN technology. Instead, it is a Layer 3 tunneling protocol used to encapsulate a wide variety of network layer protocols inside point-to-point connections. GRE is commonly used for creating VPN tunnels across IP networks, allowing for the transport of various types of payloads. This misunderstanding about GRE being a Layer 2 technology contradicts its definition and typical application ​.

A is correct – Local attack defense can classify and prioritize packets (e.g., OSPF, BGP, SSH) and ensure critical protocols are processed first by the CPU.

B is correct – The dynamic link protection function ensures session-based applications (like SSH) are not disrupted even during a CPU attack.

C is false – Different protocols have different importance levels , so individual rate limits should be configured, not a uniform one.

D is correct – CPU protection also applies to management interfaces , such as those used for Telnet, SSH, or SNMP.

Reference from Huawei HCIP-Datacom-Core Technology Study Guide:

“Devices support local attack defense by classifying packets, setting priorities, and limiting rates to protect CPU resources. These policies also apply to the management interface.”

(Chapter: Network Security – Section: Local Attack Defense)