Can a Single Multiplex Data Bus Suffice to Serve all Functions on a Transit Bus?

There have been many developments during the implementation of multiplex data standards. Several proprietary data standards have been developed by various different vendors. A few industry standards exist such as the SAE J1939 and the SAE J1708. Although the proprietary data standards have been working well, there has been some attempt to use the SAE J1939 standard for all functions on all vehicle multiplex systems on the transit bus. This caused an attempt to use one single databus for all systems on the vehicle.