This part of IEC 62343, which is a Technical Report, proposes a software and hardware interface for the optical multicast switch (MCS). This switch can be controlled by resident firmware within the interface that is intended to enable a user or host to retrieve the switch status and/or adjust relevant switch settings. The MCS is defined in IEC 62343‑3‑4. The technical information regarding MCS and its applications in dense wavelength division multiplexing (DWDM) systems is described in IEC TR 62343‑6‑4. The objective of this document is a proposal for a software and hardware interface standard of MCS.