Generally, we see customer connecting to StruxureWare using BACnet. Both the connector and the interface would do the job. If this is a new project, I think going the connector route is easier in term of configuration + automatic AF structure creation, but in essence they would both do the job.
Alternatively, some people connect via OPC, but last I checked (you should ask Schneider), there is no direct OPC Support, so BACnet device channels have to be created and then exposed as an OPC Server. The OPC Server can then be read using the PI Interface for OPCDA or the PI Connector for OPC UA.