I had assumed that the migration to Ethernet was a done deal. I guess this article is saying that it is, but that not everyone has made the shift yet. I think we're also seeing something of a taxonomy/nomenclature problem, which is something that has plagued the whole discussion of fieldbuses for a long time. Namely, Ethernet isn't so much REPLACING field buses as it is BECOMING the new, de factor field bus standard (via protocols layered on top of it for safety etc.)
Ethernet as a standard on the factory was really inevitable given the requirement to sync up production systems with front-office IT systems like ERP and even PLM. It is only with that kind of tight integration that companies can hope to garner the visibility and traceability necessary for boosting the efficiency of their production systems and moving to just-in-time manufacturing.
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