This object indicates the virtual IP address which is used to accept authentication requests from an unauthenticated host. This virtual IP address is used to accept authentication requests from an unauthenticated host. Only requests sent to this IP will get a correct response. NOTE: This IP does not respond to ARP requests or ICMP packets.
Sources for this description
D-Link official switch MIBsD-Link MIB copies (LibreNMS/Observium Community)