This read-only object reports whether Physical Topology Discovery is enabled or disabled on the Ethernet port, using the CyanEnDisabledTc enumeration. Admins use it to confirm whether the device is actively participating in neighbor/topology discovery on that port, which affects whether the network management system can automatically map connections to this port. For example, disabling topology discovery on a customer-facing port would prevent the device from advertising discovery frames that a subscriber's equipment shouldn't need to see.