Techniques are provided for metadata management for enabling automated switchover. An initial quorum vote may be performed before a node executes an operation associated with metadata comprising operational information and switchover information. After the initial quorum vote is performed, the node executes the operation upon one or more mailbox storage devices. Once the operation has executed, a final quorum vote is performed. The final quorum vote and the initial quorum vote are compared to determine whether the operation is to be designated as successful or failed, and whether any additional actions are to be performed.

Techniques are provided for metadata management for enabling automated switchover. An initial quorum vote may be performed before a node executes an operation associated with metadata comprising operational information and switchover information. After the initial quorum vote is performed, the node executes the operation upon one or more mailbox storage devices. Once the operation has executed, a final quorum vote is performed. The final quorum vote and the initial quorum vote are compared to determine whether the operation is to be designated as successful or failed, and whether any additional actions are to be performed.

The invention relates to a time-controlled distribution unit (30, 31) for the distribution of messages in a distributed computer system for safety-critical applications. Said distribution unit is designed as a self-testing functional unit and comprises input channels (201 . . . 222) for receiving time-controlled periodic input messages from node computers (20, 21, 22) upstream in the data flow, and output channels (301 . . . 333) for transmitting time-controlled periodic output messages to the node computers (50, 51, 52) downstream in the data flow, a computer (40) being provided in the distribution unit and being designed to analyze, by means of a “simple” software, useful information contained in the input messages, and to decide whether output messages are output and, if so, which useful information is contained in the output messages.

Techniques are provided for metadata management for enabling automated switchover. An initial quorum vote may be performed before a node executes an operation associated with metadata comprising operational information and switchover information. After the initial quorum vote is performed, the node executes the operation upon one or more mailbox storage devices. Once the operation has executed, a final quorum vote is performed. The final quorum vote and the initial quorum vote are compared to determine whether the operation is to be designated as successful or failed, and whether any additional actions are to be performed.

A system, in particular for controlling signal towers in rail traffic, includes at least a plurality of redundant replicants for generating redundant control signals. A voter structure having a plurality of majority voters is also provided. Each majority voter has a respective output and inputs that are connected to the outputs of the plurality of redundant replicants. The voter structure and the plurality of redundant replicants are separated from one another in terms of hardware, the outputs of the plurality of majority voters are connected to the inputs of a discriminator voter and the output of the discriminator voter provides a control signal, in particular for controlling signal towers. The discriminator voter only emits a control signal when the inputs thereof are not at variance.

A method and device for allocating a distributed lock is provided. A globally unique service process ID (SPI) is introduced for each distributed application service process while guaranteeing correctness of a distributed lock, and the SPI is used to directly manage ownership of the distributed lock. The service replacement process sends to the server a request for inheriting ownership of the distributed lock before the lifecycle of the lock file expires, the inherit request including the SPI.

A control system for an aerospace vehicle includes a voter and a plurality of control blocks. Each control block includes: a controller configured to receive an input signal and perform a control algorithm that includes an integral function on the input signal to provide an output signal; and a feedback controller that is configured to: receive the output signal from the controller, a reference signal from an external controller, and a plant feedback signal from an external plant; perform a feedback algorithm on the output signal to provide an feedback control signal; and perform a combinator algorithm using the reference signal, the plant feedback signal and the feedback control signal to provide the input signal to the controller; wherein the voter is configured to receive the output signals and perform a voting algorithm on the output signals to determine a control signal to provide to the external plant.

The invention relates to a time-controlled distribution unit (30, 31) for the distribution of messages in a distributed computer system for safety-critical applications. Said distribution unit is designed as a self-testing functional unit and comprises input channels (201 . . . 222) for receiving time-controlled periodic input messages from node computers (20, 21, 22) upstream in the data flow, and output channels (301 . . . 333) for transmitting time-controlled periodic output messages to the node computers (50, 51, 52) downstream in the data flow, a computer (40) being provided in the distribution unit and being designed to analyze, by means of a simple software, useful information contained in the input messages, and to decide whether output messages are output and, if so, which useful information is contained in the output messages.

A system, in particular for controlling signal towers in rail traffic, includes at least a plurality of redundant replicants for generating redundant control signals. A voter structure having a plurality of majority voters is also provided. Each majority voter has a respective output and inputs that are connected to the outputs of the plurality of redundant replicants. The voter structure and the plurality of redundant replicants are separated from one another in terms of hardware, the outputs of the plurality of majority voters are connected to the inputs of a discriminator voter and the output of the discriminator voter provides a control signal, in particular for controlling signal towers. The discriminator voter only emits a control signal when the inputs thereof are not at variance.

A redundant computer system utilizing comparison diagnostics and voting techniques includes a plurality of redundant channels. Each pair of the processors receives/obtains process information from I/O modules via dual redundant sensors (DRS). The processors execute an application program, whereby output module is utilized for comparing output data of the two processors. Output module receives output data from neighboring modules, if there is a deviation or other disparity in the output data. Each pair of processors, a voter and an improper sequence detector component disables the output module, if a majority of signals vote that output module fails. In addition, the system uses 2-of-3 voting, the system remains operational in the presence of up two transient or hard failures.