Communications protocols to be used for inter-unit and intra-unit serial data communications between subsystems aboard passenger trains are defined by this standard. Minimum acceptable parameters for a network that can simultaneously handle monitoring and control traffic from multiple systems are set forth. While the network is not vital, it is intended to be capable of carrying vital messages. Keywords: communications networks, communications protocol, commuter rail transit, IEEE 1473, light-rail transit, rail transit, train bus, vehicle bus. |