Pass the Huawei HCIP-Access H35-211_V2.5 Questions and answers with CertsForce

WRED (weighted early drop) uses lower and upper thresholds to determine a probabilistic drop curve; the drop probability scales with the average queue length between these thresholds—therefore D is correct.

A is incorrect because early dropping inevitably affects services to some extent; it’s designed to trade small, controlled loss for stability.

B is incorrect; devices use early drop before buffers fill, and when full, tail drop still applies—both mechanisms coexist.

C is imprecise in Huawei’s terminology; early drop begins when the average queue depth crosses the lower threshold and increases up to the upper threshold, not simply “before a preset threshold” without that two-threshold relationship.

With IGMP Snooping/Proxy on access devices (such as Huawei OLTs), multiple receiver joins for the same (VLAN, Group) are aggregated. The OLT maintains a per-group member table and typically forwards a single upstream IGMP Join toward the multicast router (or querier) for that group, regardless of how many downstream users in that VLAN have joined. Additional local joins add downstream interfaces to the OLT’s table but do not trigger extra upstream joins per user. Hence, stating that two same-program viewers cause “two join messages” upstream is wrong.

Huawei access security recommends limiting MAC learn counts per port/VLAN, and using anti-MAC-spoofing bindings: either automatic (dynamic) bindings generated by the system or manual static MAC bindings to the service/port. Simply replacing a terminal is not a network-side mitigation method and is not listed as a protection measure.

In eSight’s ONT Zero-Touch workflow, multi-service profiles define service parameters delivered to ONTs—primarily service VLANs such as Internet/Data VLAN, Voice VLAN, and IPTV/Multicast VLAN with related QoS. Hardware attributes like ONU type or Ethernet port count are part of the device/ONT profile, not the multi-service profile. A generic “Default VLAN” parameter is not used here; instead, explicit service VLANs are specified (for example, data VLAN and voice VLAN).

A: Incorrect — RADIUS typically uses UDP (1812/1813), while HWTACACS/TACACS+ uses TCP (port 49).

B: Incorrect — In RADIUS, only the user-password attribute is encrypted; fields are not selectively encrypted by user choice. TACACS+ can encrypt the entire payload.

D: Incorrect — Because RADIUS uses UDP, transport is not inherently reliable.

C: Correct — RADIUS and HWTACACS differ in message structure and returned attributes after authentication (e.g., RADIUS attribute–value pairs for access control/QoS/VLAN vs. HWTACACS command/privilege oriented responses). Thus the returned content/format differs between the two.

Huawei VLAN planning considers overall VLAN scale, user categories and volume, service types (HSI/IPTV/VoIP) and their isolation, uplink/aggregation mode (e.g., QinQ, VXLAN interwork), and device/topology constraints (e.g., OLT slot/board distribution). All listed factors affect VLAN count, tagging scheme, and scalability.

Huawei OLTs support Eth-Trunk (link aggregation) with two standard modes: Static aggregation and Dynamic aggregation (LACP). These provide bandwidth expansion and redundancy on NNI uplinks. “Automatic” is not a defined mode; and “manual” is not used as a separate mode name in OLT Eth-Trunk configuration.

On Huawei OLTs (e.g., MA5600T/MA5680T), deploying IPTV/multicast commonly uses a program list (channel list) to map program numbers to multicast group addresses—this is configured with igmp program. When programs are statically configured under the multicast VLAN, the program definitions themselves are mandatory; without them, set-top boxes cannot select (zap to) channels by program number/address mapping and the OLT cannot correctly forward the requested multicast streams.

Huawei OLTs support trust/remark mechanisms that can inherit (copy) user packet priorities (for example, trusting incoming 802.1p or DSCP to drive forwarding queues) and also support locally configured priorities (policy-based remarking/mapping on the OLT) to enforce service differentiation. Thus, both priority inheritance and local priority configuration are supported, making the statement Right.