Abstract: A method for communicating safety critical train authorization under the conditions of limited communications capability is disclosed.

Abstract: A method for reducing delays in the receipt of high priority information in a transportation system is disclosed.

Abstract: A method and system for reducing, in a centralized train control system, the portion of a centralized server application that is considered vital while not reducing the overall vitality of the system.

Abstract: A method for delivering and maintaining mandatory directives data from a central office server to an on-board system. Mandatory directives include the enforceable train control data required for a train operating on controlled track. The method enables the on-board system and the central server to exchange data in a vital manner, in part by checking for any inconsistency between i) the on-board system's data as previously transmitted and ii) the required data as represented by both a transmitted set of data identifiers and an associated error correction code.

Abstract: A method for reducing delays in the receipt of high priority information in a transportation system is disclosed.

Abstract: Methods for detecting the corruption of vital data during the execution of object-oriented programs are disclosed. In accordance with the illustrative embodiments, code is generated at run-time for computing a checksum of vital data in an object, and the code is inserted into the object. When the object is created, this code is executed to compute an initial checksum, and subsequently the code re-computes the checksum during program execution so that a change in the checksum—and inferentially, a change in one or more vital data—can be detected. The checksum is subsequently re-computed during program execution—either periodically, or in response to events such as when the object is modified or when a method of the object is invoked.

Abstract: A mechanism for maintaining configuration or other vital data outside of source code is disclosed. In accordance with the illustrative embodiment of the present invention, a data manager software component serves as an interface between an external configuration data store and one or more applications, processes, and threads. In contrast with techniques of the prior art, the illustrative embodiment does not suffer from the risk of undetected corruption of vital data, and therefore is especially advantageous in safety-critical systems.

Abstract: A method for communicating safety critical train authorization under the conditions of limited communications capability is disclosed.

Abstract: A method and system for reducing, in a centralized train control system, the portion of a centralized server application that is considered vital while not reducing the overall vitality of the system.

Abstract: A method for delivering and maintaining mandatory directives data from a central office server to an on-board system in an efficient and vital manner is disclosed.

Abstract: The present invention provides a way to automate the hand-off of train control in a rail system and handle failover.