transmission mode where each node of a communication network can initiate the transmission of a message as soon as the bus is free
NOTE 1 (see 3.2.7 NOTE: 2). As every node can initiate a message transfer (multi-master), a direct message transfer between all nodes of the network is possible.
NOTE 2 It is expected that each node of a Multi-master- network is able to autonomously contend the bus to initiate the transmission of a message. As it can happen that more than one network node begins transmission of a message at the same time, an arbitration process is necessary, which ensures only one node actually continues with the transmission of its message.
NOTE 3 Compared to a cyclic message transfer, a considerably lower bus load or a reduction in the required data transmission rate results.