The repeaters, couple by the lines are an independent electric segment where the signals can be terminated optimally. This helps in implementing topologies with bus line connection due to electrical reflections.
As per the output capacities from the transceiver, the number of bus nodes can be increased by the division of CAN/CAN FD system into subsystem which is connected via CAN/CAN FD repeaters.
The real-time behavior of a system is not influenced by using repeaters, as it corresponds to the behavior of the transmission where the network consists of only lines. Repeater in terms of signals corresponds to a line with relevant delay time and thereby the CAN/CAN FD system cannot be extended. The system dimensions are increased indirectly by using repeaters.
Sources:- Elektronik Praxis