I read that a TSN Testbench has been released as an open source project and is now available to everyone. What is this TSN Testbench for, who is it for and how does it help me?

Is the Ethernet APL test a prerequisite for PROFINET certification of APL devices?

Which areas are covered by PI certification testing for APL?

Is intrinsic safety /APL physical layer certification required prior to PROFINET certification??