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

WRED (Weighted Random Early Detection) helps prevent congestion by randomly discarding packets before buffers are full.

Drop Probability Behavior:

Below lower threshold = 0% drop (packets pass normally).

Between lower & upper threshold = Progressively increasing drop probability.

Above upper threshold = 100% drop (probability = 1).

✅ Reference: Huawei HCIE-Datacom Guide - WRED Mechanism

An IPsec Security Association (SA) includes the following critical components:

SPI (Security Parameter Index)

Destination IP address

Security Protocol (AH or ESP)

Encryption/Authentication algorithms

The Source IP address is not a defining parameter of an SA. SA is unidirectional and identified based on the SPI and destination address.

Exact Extract - Huawei Security Configuration Guide – IPsec Fundamentals:

“An SA is uniquely identified by the SPI, destination IP, and security protocol. The source address is not a determining factor in the SA.”

OSPFv3 (used for IPv6) uses IPv6 multicast addresses for 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 is not applicable 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