Bit Synchronization:
There is no separate clock signal on the CAN bus to synchronize the node the CAN frame itself is used for synchronization of the clocks on all the nodes.


There is hard synchronization and soft synchronization of node clocks using the CAN frame while all nodes have clocks running at the same baud rate. When the transmitting node sends a CAN frame all the clocks of the receiving nodes are synchronized to the transmitter clock at the falling edge of the “Start of Frame” (SOF) bit. This is the hard synchronization of the clocks.
Subsequent falling edges of the CAN frame are used for soft synchronization of the nodes. The difference between the hard synchronization and soft synchronization is that the sampling clock cannot shift by more than a specific amount indicated within the CAN specification.