Patent ID: 8090486
Filing Date: 2012-01-03
Classification: B61L

Abstract:
1. A method comprising: receiving, by an on-board system situated on a train, a first message containing a set of mandatory train directives that comprise train control data for the train; subsequent to receiving the set of mandatory train directives, receiving a plurality of regularly-transmitted heartbeat messages at a train; wherein a heartbeat message from the plurality includes i) a current set of data identifiers and ii) error detection code associated with the current set of data identifiers; wherein the heartbeat message from the plurality does not include the train control data; and wherein the error detection code comprises a smaller data set than the set of mandatory train directives; comparing, for a discrepancy, the error detection code in each heartbeat message, when received, against a copy of the mandatory train directives that is stored in the onboard system; and altering a normal operating mode of the train to a relatively more restrictive operating mode when a discrepancy is identified.