Edge on OPC Proxy

In this setup, the edge is not directly connected to the OPC Classic server, but is instead connected through an OPC Proxy by means of its OPC UA client interface:

An OPC Proxy enables the OPC Classic server, which is based on the COM/DCOM architecture, to be connected with the OPC UA products and can be used to manage the traffic in both directions at the same time. It typically wraps an OPC UA server that gets data from its internal COM client. The wrapper is needed to connect the OPC UA client to the OPC Classic servers. As a proxy, it supports the traffic in the opposite direction. The proxy is a COM-based server that gets its data from its internal UA client. The proxy is needed to connect OPC Classic clients to OPC UA servers. It can also be used for firewall tunneling a COM/DCOM-based OPC through a secure OPC UA connection.

In this setup, the OPC Classic server collects data from the related underlying device. The data gathered through DCOM from the OPC Proxy linked to the same network of the OPC server is tunneled in a TCP channel across the network boundary to reach the other OPC Proxy on the other side of the TCP channel. This OPC Proxy exposes the data through its OPC UA internal server, therefore making it available to the OPC UA client interface, which implements and incorporates it into the edge to be later transferred to the cloud. Like the previous scenario, in this setup, the data source could be a PLC, a DCS, a SCADA system, or a Historian, since the OPC abstracts the data source.