Analysis of the Train Communication Network Protocol Error Detection Capabilities
The Train Communication Network (TCN) has been adopted as an international standard for use in critical transportation applications on trains. This paper discusses the results of a general review of the specification for error detection properties as an important factor of overall system safety. In general, TCN has excellent error detection properties and is much more thoroughly specified in this regard than other embedded network protocols. The only significant recommendation for improvement is prohibiting the use of variable- or multiple-length frames for any particular frame ID value to guard against corruptions that can cause undetected changes in message lengths (current implementations use only single lengths, but this is not specifically required by the standard). Additionally, it is important that designers pay close attention to receiver circuitry to minimize vulnerability to “bit slips” that could cause phase shifting and resultant burst errors in received Manchester-encoded bit streams.