On Huawei access devices/OLTs, VoIP/H.248 setup typically includes:

In voip view, configure media IP with gateway:

ip address media – e.g., ip address media 10.10.10.10 10.10.10.1.

Configure signaling IP without a gateway parameter:

ip address signaling – e.g., ip address signaling 10.10.10.10.

Add/enter the H.248 interface and apply properties with if-h248 attribute ….

It’s common to reset/enable the MG interface after attribute changes; many guides show reset coldstart (or reset) issued under the H.248 interface to activate the interface.

Authoritative configuration examples show media takes an IP and gateway, but signaling takes only the IP. Therefore, option D (attempting to configure signaling with a gateway parameter) is incorrect. Options A and C match documented syntax and workflow. Option B reflects the documented practice of issuing a reset (often written as reset coldstart) under the H.248 interface to apply/enable, as shown in Huawei-focused configuration guides.

Right. The SIP Max-Forwards header limits how many SIP elements a request can traverse. Each proxy decrements the value by one; when it reaches zero, the message must not be forwarded, preventing infinite loops and yielding responses like 483 (Too Many Hops). RFC 3261 (Sections 8.1.1.6, 16.6, 20.22) defines this behavior; later work further discusses loop mitigation

Huawei multicast guidance stresses IGMP version compatibility: devices running an earlier version must interoperate only with hosts using the same or earlier version, otherwise v3 messages may not be processed. In Huawei’s multicast feature guidance for access devices (OLT side vs. user side), the behavior documented is that when the device is operating in IGMPv2, IGMPv3 Report messages from terminals are not processed—interoperation is restored only after the terminal/device side is downgraded to v2 (often driven by periodic queries that induce hosts to respond in v2). This maps operationally to dropping unsolicited IGMPv3 Reports when the OLT is fixed to v2. Huawei also recommends ensuring the device runs an IGMP version the same as or later than member hosts to avoid such loss. Therefore, with OLT fixed at v2, an incoming v3 Join is discarded.

Type B protection (OLT-side + feeder protection via 2×2 optical splitter) is designed for automatic protection switching (APS) upon detecting faults such as LOS/LOF on the working port or feeder. The system automatically switches to the standby PON port/feeder without manual intervention (manual cutover is optional but not required for protection).

(Reference: HCIP-Access V2.5 – GPON Type A/B/C protection definitions, trigger conditions, and APS behavior.)

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).

Huawei’s alarm reference for PON ports lists the common possible causes of LOS (the OLT does not receive the expected optical signal) as:

The port laser is shut down;

The backbone optical fiber connected to the port is faulty;

All the ONTs/ONUs connected to the port are powered off or faulty;

(and potentially) port hardware faults.

These map directly to options D, B, and C. A rogue ONU generates specific “rogue ONU” alarms and is characterized by continuous/abnormal upstream emission; it is not a typical root cause of an LOS condition, which indicates absence of expected optical signal.

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.