The end user may have a requirement to have more than one identical hub attached to the system. Therefore, it is important to verify that the device application and device driver operate with multiple identical hubs attached to the system.
Using the same hub tree as the Fifth Tier Operation - UHCI test, add the second Hub Under Test using a five metre cable to a spare port on the tier four hub.
Ensure both hubs are fully functional:
Hot attach - no installation is required.
Application installation - if required to show functionality
Warm boot - system remains functional
Cold boot - system remains functional
Asynchronous detach and reattach
USB topology change - no driver modification required