by Support Team » 09 Apr 2019, 17:03
Hello gingmeng,
OPC UA specifies different transport mechanisms, they are defined by part 6 of the OPC UA specification.
"UA-TCP UA-SC UA-Binary" is indicated by the opc.tcp schema and is the default mechanism that has to be supported by every OPC UA application.
"HTTPS UA-Binary" is indicated by the https schema and is an additional mechanism that uses the HTTPS transport and OPC UA binary encoding.
The default opc.tcp transport can be used everywhere, it is not necessary to switch to HTTPS if the communication goes through the internet. HTTPS is only necessary if there are security mechanisms (e.g. firewalls) that don't allow other traffic. HTTPS also has technical limitations, which is why we only have experimental support for it.
Best regards
Unified Automation Support Team