Machine Integrator offers a rapid data capture and can be used to capture information and perform transactions
Data capture rate does not depend on how many Client or Local MIs are running. Installing additional Client or Local MI instances doesn't scale the transaction rate (though it does reduce risk and simplify administration).
Data sampling, which Apriso can do may provide similar functionality with possibly slower rates of data capture.
Most Historians can function as OPC-DA servers, and they can be accessed using Machine Integrator
Historians often have web based front end screens which can be embedded within Apriso operator screens
Historians offer functionalities which enhance what MI can do:
Data compression where they can calculate missing gaps in data
Excellent performance for capturing and reading values (in the thousands of records written per second), read millions of records per second etc.
