scope:

This standard defines the protocol for intercar and intracar serial data communications between subsystems aboard passenger trains. It sets forth the minimum acceptable parameters for a network that can simultaneously handle monitoring and control traffic from multiple systems. While the network itself is not vital, it is intended to be capable of carrying vital messages. This standard will be structured with respect to the OSI seven-layer model.

Purpose

A standard protocol will permit systems provided by a variety of suppliers performing different on-board functions to share a common communications facility. Car wiring and weight will be reduced while systems integration, reliability, and maintainability will be improved.