The mandatory network planes are the backup network and the management network.

Huawei defines the management network plane as the network used for web-console login, service configuration, and alarm reporting. Without it, administrators cannot perform the fundamental control and administration functions required by the appliance. Huawei defines the backup network plane as the network used for backup data and in-band signaling transmission, making it essential for the appliance ' s core data-protection function.

The replication network, by contrast, is needed when backup copies must be replicated to another data-protection appliance. If remote replication is not part of the deployment, this plane is not mandatory. Similarly, an archive network is optional because the backup network can be reused for archiving under supported configurations.

An internal communication network becomes relevant to multi-node architectures where separate nodes must communicate internally. The question explicitly specifies a single-node system, so this separate internal plane is not mandatory.

Therefore, the baseline single-node OceanProtect networking requirement is C and D.

Study Guide Topics: Data Protection Solution → OceanProtect Appliance → Network Planning → Management Network → Backup Network → Replication Network.