Throughout the years, the CAN protocol has been adapted to specific applications and is now available in there three variants: HS-CAN (high speed), FT-CAN (fault tolerant), and SW-CAN (single wire). The FT-CAN protocol arose from a need for a fault tolerant communications network which continued to operate even if one of the wires was disconnected. Although this configuration had many advantages, its one major drawback was a reduced communication speed. In the last few years the demand for FT-CAN has declined while demand for SW-CAN and HS-CAN has increased. SW-CAN is a single wire system intended for non-critical functions.