The present invention relates to message loss prevention by using sending and receiving buffers, and especially provides a vehicular distributed embedded real-time controller area network system including ECUs functioning in an event-triggered mode for initiating transmission of a message to a communication bus. Each ECU includes a sending buffer for storing message. A bus controller interfaces with the ECUs and manages the transfer of messages to and from the communication bus. The transfer of messages onto the communication bus is executed by the bus controller on a periodic basis. The bus controller is unavailable to receive a message from an ECU when a previous message stored within a memory of the bus controller is awaiting transmission on the communication bus. The bus controller is available to receive a message from an ECU when the memory is empty. Messages are stored in the sending buffer when the bus controller is unavailable. A respective message within the sending buffer is transferred to the bus controller when the bus controller is available.