This reports the ifIndex dynamically assigned by the agent to a virtual network interface, valid whenever the row's status is active, with its ifType reflecting the underlying interface type: fibreChannel(56) for a VSAN or ethernetCsmacd(6) for a VLAN. An admin cares because it's the bridge between this virtual-interface-specific table and the standard interface table, confirming which physical media type the virtual interface maps to. For example, a virtual network interface of VSAN type would show up in the standard interface table with ifType fibreChannel(56), letting standard interface tools correctly interpret it.