Huawei H35-211_V2.5 HCIP-Access V2.5 Exam Practice Test

Huawei digitmap syntax uses x to represent any single digit 0–9. To match a 7-digit number starting with 7727, the correct pattern is 7727xxx.

A adds an unrelated rule 7726. and uses . incorrectly as a wildcard; not recommended.

B uses 772. (invalid for the intended match) plus 7727xxx; the first part is improper.

C matches only the 4-digit string 7727.

D contains 7727xxx (correct) and an additional 7727 rule; although the extra rule is unnecessary, it does not prevent correct matching.

For Huawei uplink protection (STH-NNI port protection) with workmode timedelay, the mandatory steps are:

Create/define the protection group with the protect-target and workmode timedelay;

Add member ports with roles (work/protect);

Enable the protection group.

Interface-level timers like offline-tx-off-time under the physical interface are not required for standard timedelay protection operation and are therefore optional.

In Huawei IPTV troubleshooting, mosaic/flash/jerky or intermittent picture typically results from packet loss or bit errors. Common causes include: optical power near the receiver sensitivity threshold causing FEC/BER spikes (A); loss of I-frames (key frames) either in the encoder/compression stage (B) or due to line transmission loss/jitter (D); and device rate-limit (CAR/policing) misconfiguration that drops packets under burst traffic (C). Any of these can yield unstable display.

IGMP Snooping is a Layer-2 function that listens to IGMP control packets between hosts and the multicast querier. Upon receiving a host’s Membership Report (Join) for group G, the switch learns that the ingress port is a member port for G and adds that port to the group’s forwarding entry, so multicast traffic for G is forwarded only to those learned member ports (saving bandwidth and avoiding flooding). Huawei’s official documentation describes IGMP Snooping exactly in this way.

In AQM, high-priority queues are given more tolerant (larger) thresholds so they are less likely to be dropped early. Setting a smaller early-drop threshold for high priority would increase their loss probability, which contradicts QoS objectives—thus A is incorrect. Descriptions in B, C, and D align with Huawei’s treatment of congestion avoidance: RED/WRED proactively drops to stabilize queues and can reduce delay variation; tail drop at full buffer can lead to global TCP synchronization.

Huawei anti-DoS on access boards performs periodic detection. Ports with consecutive detections of abnormal traffic are placed into a blacklist/quarantine state. The system then applies a random back-off interval before re-detecting; if no further anomalies are found, the port can be automatically removed from the blacklist.

In U2000’s IPTV/IGMP service model, the IGMP template suite includes: Permission templates (program authorization), Multicast user templates (user IGMP attributes), Program templates (program/group definitions), and Preview parameter templates (preview/fast-zapping parameters). These cooperate to control user authorization, program mapping, and IGMP behavior.

For intercommunication across VLANs—especially for voice between ONUs—ARP Proxy is configured on the OLT so the OLT responds to ARP on behalf of endpoints and bridges traffic across VLAN boundaries without exposing the full L3 gateway to each segment.

A: “Saving IP addresses” is not the defining difference; ARP Proxy’s function is ARP mediation to enable L2/L3 reachability.

B: Both features target intercommunication, not isolation.

D: A VLAN service-profile is planned and applied from the OLT side to ONUs; it is not “configured on the ONU” directly for this purpose.

In IEEE 802.1AX/802.3ad LACP operation, timeout detection relies on a multiplier of three consecutive LACP intervals. In short-timeout mode, the default period is ~1 s; if 3 intervals pass without receiving LACPDUs, the peer is considered expired and the member is removed (treated as Down for aggregation). Huawei implements this standard behavior for port-member validity in an Eth-Trunk.

(Reference: HCIP-Access V2.5 – Link Aggregation/LACP timers and member aging; IEEE LACP short-timeout 3× interval rule.)

In Huawei GPON/EPON protection planning, Type B protection uses two PON ports on the same OLT with dual feeder (trunk) fibers into the same ODN. It protects the OLT PON port and the feeder/trunk optical path while branch/distribution fibers to ONUs are not protected. This exactly matches the requirement “protect trunk; do not protect branches.”

In SIP, each proxy/server that forwards a request prepends its own address to the top of the Via header list. Therefore, as A’s INVITE traverses C, then D, then E, server E adds its Via at the top last, followed by D, then C below it. The message that reaches user B shows the Via stack (top→bottom) as E → D → C, which corresponds to option C. RFC 3261 states that the server transport uses “the value of the top Via header field” to determine response routing, confirming that the most recent hop is at the top

A single-layer VLAN is limited by the IEEE 802.1Q VLAN ID space (1–4094), i.e., about 4K VLANs. In large PON deployments, when you must separate multiple services (e.g., HSI, VoIP, IPTV) and the user scale approaches or exceeds the 4K ceiling, a dual-layer VLAN (QinQ) design is required to extend the VLAN namespace and implement hierarchical isolation (access VLAN + service/aggregation VLAN).

The MG reports availability and restarts to the MGC using H.248 ServiceChange with Method=Restart. The Reason code distinguishes the type of restart. In Huawei implementations aligned with H.248 semantics, Reason=[901] corresponds to a warm/warmboard restart scenario rather than a full cold start.

Board restart triggers a warm restart of the voice board/MG, producing ServiceChange { Method=Restart, Reason=901 }.

Reset coldstart performs a cold start, which would use a different reason code (cold start), not 901.

Reboot system generally implies a broader device reboot similar to cold start semantics, not 901.

ONT re-register affects ONU registration and does not cause the MG to announce a ServiceChange restart to the MGC.

In GPON, DBA (Dynamic Bandwidth Allocation) operates in the upstream direction. The OLT grants upstream transmission opportunities to ONTs by assigning T-CONT bandwidth (Fixed/Assured/Non-Assured/Best-Effort) within upstream frames. The downstream direction is a continuous broadcast stream from the OLT at the fixed GPON line rate; user traffic is multiplexed without DBA. Hence, DBA is upstream-only; downstream traffic is not DBA-scheduled.

Huawei GPON design recommends at most two splitting stages and a total split ratio within the optical power budget (commonly up to 1:64 for standard budgets).

A: 1:2 × 1:16 = 1:32 (valid).

C: 1:8 × 1:8 = 1:64 (valid under standard budgets).

D: 1:2 × 1:8 = 1:16 (valid).

B: 1:16 × 1:16 = 1:256, which exceeds typical GPON budgets and recommended engineering practice. Hence B is the incorrect networking.

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.

OLT-level (device-level) protection is achieved by dual-homing ONUs to two independent OLT interfaces so that services can switch to another OLT when one fails. In Huawei protection taxonomy, the dual-homing scheme (as contrasted with single-homing) provides device-side redundancy for the OLT. By comparison, Ethernet port protection groups and LACP protect uplink links and bandwidth at Layer 2, not the OLT device itself; single-homing does not protect against OLT failure.

PITP (Port Identification Transparent Transmission) is used on access networks to carry a user’s physical access-location to the upper AAA/BRAS. It has two working forms: P-mode (PPPoE+)—injecting location identifiers into PPPoE discovery—and V-mode (Vendor-tag)—carrying vendor/location tags transparently upstream. The purpose is to let the upper server associate user credentials with access location and, by policy, restrict roaming. Options A, B, D, and E correctly describe these behaviors/terms. Option C is inaccurate as written: PITP itself does not “bind the authentication” or inherently “avoid theft/roaming”; it only delivers location info. Preventing credential theft/roaming is achieved by AAA/BRAS policy that uses the PITP-carried location, not by PITP alone.

In Huawei QoS processing, traffic classification on access devices/OLTs can match Layer-3 and Layer-2 priority indicators and MPLS labels. Common match fields include IP DSCP (or IP precedence in the ToS byte), MPLS EXP, and IEEE 802.1p CoS carried in VLAN tags. These fields are used to place packets into scheduling/queuing behaviors and policing profiles.

Huawei Anti-MAC-Spoofing binds the source MAC to the service flow/port to prevent address forgery. It is functionally exclusive with certain per-VLAN MAC check features (e.g., WMAC, SC, PPPoe-SMAC) to avoid conflicting validation logic. For IPoE users with fixed IP, operators typically configure static bindings/entries so that address and access policies remain consistent.

Option D is wrong: disabling Anti-MAC-Spoofing and removing fixed entries can affect service behavior; if forwarding is interrupted, that does impact user service—so the statement is self-contradictory and incorrect.

In IPTV/multicast access scenarios, channel zapping delay is heavily influenced by how fast the network stops forwarding the previous channel’s stream after a user switches. Huawei documents the IGMP Fast Leave/Prompt Leave feature, which enables the access device to immediately prune the old multicast group on receipt of a Leave (without waiting for group-specific queries and timers), thereby reducing the channel change delay and improving perceived switching speed. Option A explicitly disables a helpful pre-join optimization, which would worsen experience; Option C (preview) concerns showing brief previews and is not a primary mechanism for shortening zapping time; Option D is unrelated to performance. Thus, enabling Quick/Fast Leave is the correct action to shorten switching time.

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.

10G-EPON is designed for coexistence with EPON on the same ODN by using separate downstream wavelengths and dual-rate upstream mechanisms. Operators can realize a smooth upgrade at the OLT (local end) by inserting WDM mux/demux modules (or using dual-rate PON ports) while continuing to use the existing ODN fiber plant and splitters. This is a standard migration path emphasized in HCIP-Access materials for PON evolution.

For enterprise/private multicast, Huawei adopts the administratively scoped range 239.0.0.0/8 for internal multicast groups. 232/8 is typically used for SSM in public domains, 224/8 contains link-local and well-known groups, and 225/8 is not defined as the preferred private scope.

For IP-based discovery, eSight relies on Layer-3 reachability and SNMP/ICMP. Being on the same subnet is not required; that condition applies to broadcast/ARP discovery. Required conditions include proper permissions, IP connectivity, and aligned SNMP parameters.

On Huawei OLTs, the service-port is a binding between the user-side access (ONT/port) and a VLAN/GEM channel, and it supports traffic policing (CAR/rate-limit) by referencing a traffic/queue profile. Traffic shaping (buffer-based smoothing, token bucket with queue drain) is provided on ports/queues or GEM/LLID directions, not on the service-port object itself. Therefore, shaping is not performed via the service-port; applying a traffic profile there enforces policing, not shaping.

IGMP is the host-side membership protocol: the first-hop router (querier) uses IGMP Queries/Reports/Leaves to manage host participation in multicast groups and to ensure forwarding state reflects receiver interest. PIM-DM/PIM-SM build distribution trees between routers, and MSDP shares source information between PIM-SM domains—they are not used by hosts.

Per RFC 3261 (SIP), “The CSeq header field of the response MUST equal the CSeq field of the request.” CSeq carries a sequence number and the method, thereby associating a response with the specific request it answers. While Call-ID ties together all messages within the same dialog, it does not identify the specific request/response pairing; CSeq does. Therefore, CSeq is the correct header for correlating a response to the exact request.

On Huawei VRP, Advanced IPv4 ACLs (which can match source IP, destination IP, and L4 port numbers) use the 3000–3999 numbering range.

2000–2999 = Basic IPv4 ACL (matches source IP only).

3000–3999 = Advanced IPv4 ACL (matches source/destination IP, protocol, ports).

4000–4999 = Layer 2 (MAC) ACL.

5000–5999 = User-defined/other ranges, not the standard advanced IPv4 range.

Therefore, to match IPs and ports, select 3000–3999.

Huawei OLTs support ONT replacement without deleting the original service profile by using ONT replace/auto-find mechanisms. The OLT can bind the new ONT (new SN) to the existing ONT configuration template (service-port, VLAN, QoS, multicast profile, etc.), achieving a smooth replacement without manually removing and re-creating the ONT and services. The statement that you must remove the ONT and re-register from scratch is therefore wrong.

Huawei access devices apply a deterministic service-flow match order for upstream user packets. VLAN-based matching is attempted first. If no specific service flow matches and TLS (Transparent LAN Service) is configured, the system falls back to the TLS service flow as the default L2 transparent handling for that port/user, ensuring service continuity without explicit per-VLAN bindings.

In IP multicast, only one copy per multicast group (program) is forwarded upstream, regardless of how many users are watching it. Replication happens downstream at the access/edge, not toward the core. Therefore the upstream traffic equals the number of active multicast groups × per-group bitrate:

20 programs × 2 Mbit/s = 40 Mbit/s.

This behavior is consistent with Huawei’s multicast feature descriptions and general multicast principles (IGMP/PIM), which explain that multicast traffic is sent as a single flow per group and replicated only where branching occurs, not multiplied by user count.

A (True): Huawei multicast configuration defaults commonly allow a user to watch up to 8 programs simultaneously unless overridden (e.g., max-program-num default 8 in multicast/VLAN views and controllable multicast profile).

B (True): On Huawei access devices, IGMP Reports from users are processed by the line card (board) logic/CPU as part of IGMP Snooping/controllable multicast handling to build forwarding entries. (See Huawei IGMP Snooping/Proxy architecture descriptions.)

C (Incorrect): IGMP Snooping is a Layer 2 function, but IGMP Proxy is a Layer 3 function (runs on a gateway to originate Queries and proxy membership upstream). Grouping them together as “Layer 2 global parameters” is incorrect. Huawei documentation distinguishes IGMP Snooping (L2) from IGMP Proxy (L3).

D (True in practice): When automatic matching is not used, multicast program groups/channels must be configured so that user joins map to provisioned program entries (consistent with Huawei controllable multicast/BTV configuration workflows).

XG-PON (10G GPON) adopts XGEM framing. Compared with GPON’s 12-bit GEM Port-ID, XGEM expands the Port-ID field to 16 bits, increasing the number of logical data flows that can be identified per ONU/OLT and improving service granularity. Hence the correct length is 16 bits.