The ACCESS clause, which need not be present, is used to indicate the agent provides less than the maximal level of access to the object or notification named in the correspondent VARIATION clause.
The only value applicable to notifications is "not-implemented".
The value "not-implemented" indicates the agent does not implement the object or notification, and in the ordering of possible values is equivalent to "not-accessible".
The value "write-only" is provided solely for backward compatibility, and shall not be used for newly-defined object types. In the ordering of possible values, "write-only" is less than "not- accessible".