As the demands for nodes, transfer rate, and cycle times have been increasing, it led to bottlenecks that created the limitations of classic CAN. The size for classic CAN is 8 data bytes and 1 Mbit/s as the data rate. The network expansion was depended on the data rate and for service and analog data, the short data length played an important role.
Due to compromises, these limitations were often circumvented in daily uses. The system division into different network segments with various applications or parallel networks also meant that existing technology is being exhausted constantly which often led to solutions that are complex and expensive in configuration, setup, and maintenance terms.
Thereby, the performance can be switched to an industrial Ethernet technology where the level of investment is increased that is usually necessary. The data structure that needed to change and the thinking mode for the configuration, mainly for the time-controlled system is often considered as a challenge in an extensive network.
Additionally, switch tools for development, commissioning, and service are necessary where many users are deterred from a complete conversion but at the same moment, know-how is a need.
So, CAN FD can be defined as an extended version for well-known “classic” CAN that was introduced in 2012 by Bosch and the usable data rate and data length were significantly extended. CAN concepts have been tried and tested, and they have been retained as arbitration that is based on message IDs, messages with event-driven dispatch, and messages with acknowledgment by means of the acknowledgment bit?
Source:- CAN