Industrial applications use unidirectional gateways (See NIST 800-82r2). The gateways have diode-like hardware at their core, but add software. The software acquires snapshots of industrial state, converts those snapshots to proprietary unidirectional protocols & formats, and on the external enterprise network makes the data available to enterprise users.
A common example is a SQLServer database of all industrial data that is authorized to share with the enterprise. Grab new and changed data as it arrives on the industrial side. Push unidirectionally to the enterprise side. Insert/update the data in an identical SQLServer. Enterprise users & applications interact normally and bi-directionally with the replica database.
The technology is used routinely to provide access to industrial data that enables business efficiencies, without providing access to the industrial systems that produce the data.
A common example is a SQLServer database of all industrial data that is authorized to share with the enterprise. Grab new and changed data as it arrives on the industrial side. Push unidirectionally to the enterprise side. Insert/update the data in an identical SQLServer. Enterprise users & applications interact normally and bi-directionally with the replica database.
The technology is used routinely to provide access to industrial data that enables business efficiencies, without providing access to the industrial systems that produce the data.
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