A good question now is,"What parameters and design requirements define a suitable application for CAN?" The factors listed here are among those to consider. This serial data communication technology provides communication at up to 1Mbps at distances up to 40 meters for high-speed CAN 2.0B. For low-speed CAN 2.0A, the capability is up to 125kbps at distances up to 500 meters. Both CAN versions are good choices for systems that must perform dependably in noisy, difficult environments. The CAN reliability features previously described reduce the probability of an undetected bad message to a low level: less than 4.7 x 10-11. This is virtually a 0% failure rate. A CAN implementation can have over 100 nodes, or individual MCUs, depending on the Physical layer of the network. Because the CAN bus is not controlled by a single master node, all nodes can negotiate for the bus and send messages. This makes possible intelligent, redundent systems. A defective network node doesn't disable the network. The 1Mbps maximum transfer rate that the CAN 2.0B bus delivers includes the overhead imposed by the network protocol. At that speed, the net transfer rate for message data is 577kbps. The priority of a CAN message is determined by the numerical value of its identifier. The message with the lowest numerical value ID in its header has the highest priority. It wins if another node with lesser priority tries to transmit at the same time.