Not sure if you want to talk licences on vCampus...but I will post questions on the subject until I know otherwise.
What are the licence restrictions with the OPC DA server with regards to connecting to numerous PI systems from a single interface machine. What I can see is on Box 'A' I can install OPC DA/HDA, add connections to 10 different PI servers to Box 'A' PISDK (these then appear when browsing OPC.DA.1 on BoxA) and all points are obtainable on the 10 PI servers.
If an interface was written to query Box 'A' via OPC for all 10 PI systems for various PI tags, would this be in violation of any licencing (assuming there is no Enterprise Agreement or special arrangements between client & OSI)? So in theory Box 'A' is a hub for data requests & events.