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

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 IP address discovery mode, eSight does not require L2 same-subnet adjacency; it only requires IP reachability/routing, proper SNMP credentials/alignment, and the operator’s Resource Access permission to poll and add devices. The “same network segment” prerequisite applies to ARP broadcast discovery mode, not to IP address discovery.

For IPv4 multicast, the destination MAC is derived by mapping the lower 23 bits of the multicast IP address into the OUI 01-00-5E. The 4th MAC byte is the lower 7 bits of the IP’s second octet (so it ranges 00–7F), and the 5th and 6th MAC bytes are the third and fourth IP octets directly:

Multicast OUI: 01-00-5E

IP: 227.120.1.32

2nd octet = 120 (0x78). Its lower 7 bits are still 0x78 (since the MSB is 0).

3rd octet = 1 (0x01)

4th octet = 32 (0x20)

Therefore the MAC is 01-00-5E-78-01-20 → option C.

(This mapping aligns with standard IPv4 multicast-to-Ethernet rules described in Huawei’s multicast overview sections in HCIP-Access materials and Huawei OLT product guides.)

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.

Standard OTDR operation allows you to configure multiple acquisition parameters:

Measurement range (distance range): sets the maximum span to be traced; best practice is typically 1.5–2× the fiber length under test.

Wavelength: select test wavelength(s), e.g., 1310/1550 nm for SM fiber, to observe different loss characteristics.

Mode: vendors provide real-time/average (or similar) acquisition modes to stabilize traces.

Pulse width: controls dynamic range vs. event resolution; longer pulses see farther but increase dead zones, while shorter pulses improve resolution at the cost of range.

These are documented in foundational OTDR references and application notes.

In campus/access networks, IGMP (Internet Group Management Protocol) operates between hosts and the first-hop multicast router/querier on the local subnet. It controls host group membership (Join/Leave/Query/Report), allowing the device to learn which receivers are interested in specific multicast groups and to populate/maintain the local multicast forwarding state.

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.

In H.248, the MGC controls the MG by creating a Context (also called an empty connection) and then adding terminations to build point-to-point, multipoint, or conference topologies. During call setup the MGC typically creates an empty context first, then binds terminations as media is negotiated.

A is incorrect: contexts and terminations can be modified during the session.

B is incorrect as written (the association/context is released, not “used”).

C is incorrect: an MG limited to point-to-point cannot host three or more endpoints in one context.

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.

SNMPv2c uses a community-string model (clear-text “read”/“write” strings) and provides no authentication integrity or encryption. Only SNMPv3 adds auth/privacy (AuthNoPriv/AuthPriv) with hashing and encryption. Therefore, stating that SNMPv2c can encrypt user passwords is false.