ADN-MIB::adnsonetMediumStatus is a bit-mapped integer field that shows all defects affecting the physical medium (fiber optic connection) simultaneously—laser degradation, signal power loss, applique failures, and others are summed into one number. Engineers read this status to quickly diagnose whether the optical interface hardware is healthy and whether multiple fault conditions exist at the same time. A value of 1 means no defects detected; a value of 7 (1+2+4) indicates three different defects are active—such as laser degradation and signal loss together.