The following section details the generic MDISDiscreteInstrumentObjectType structure and defines the properties associated with it. Additional sections define a subtype MDISDiscreteOutObjectType that allows updates to the discrete value. This is in general a vendor and operator independent description, but all users of the MDISDiscreteInstrumentObjectType or MDISDiscreteOutObjectType can add vendor specific data. The vendor specific data should be defined as part of a subtype of the MDISDiscreteInstrumentObjectType or MDISDiscreteOutObjectType defined in this document. It is assumed that the subsea system is the Server and host of the instance of the MDISDiscreteInstrumentObjectType or MDISDiscreteOutObjectType. The DCS based system is the Client in the system. It is assumed that all interactions with the instance of the MDISDiscreteInstrumentObjectType are initiated by the Client and are directed to the Server.