Abstract: A system for time synchronization over redundant switch-based avionics networks is disclosed. The system includes a master or source clock for determining precise UTC timing information from received satellite signals and generating time marks based on the timing information. The source clock generates network-compatible timing messages and forwards the timing messages to network switches within the switch-based avionics networks. The network switches modify the timing information to account for switch-based delays and forward the modified timing messages to destination clocks in aircraft end systems. The end systems relay timing messages back to the source clock via the network switches, the timing information again modified by the network switches according to switch-based delays, and based on the precise timing information exchanged destination clocks in end systems throughout the switched network can precisely synchronize to the source clock.

Abstract: A system for an airborne platform includes a network controller, a first subsystem having a number of devices configured to communicate a first data type, and a second subsystem having a number of devices configured to communicate a second data type. The network controller includes a processing circuit and is communicably coupled to the first subsystem and to the second subsystem. The processing circuit is configured to receive data relating to the first data type over a first plurality of communication channels and data relating to the second data type over a second plurality of communication channels. The processing circuit is further configured to multiplex the data relating to the first data type and the second data type to a multiplexed data stream configured for communication over a single communication channel. The processing circuit is further configured to transmit the multiplexed data stream over a data transmission line.

Abstract: A system for time synchronization over redundant switch-based avionics networks is disclosed. The system includes a master or source clock for determining precise UTC timing information from received satellite signals and generating time marks based on the timing information. The source clock generates network-compatible timing messages and forwards the timing messages to network switches within the switch-based avionics networks. The network switches modify the timing information to account for switch-based delays and forward the modified timing messages to destination clocks in aircraft end systems. The end systems relay timing messages back to the source clock via the network switches, the timing information again modified by the network switches according to switch-based delays, and based on the precise timing information exchanged destination clocks in end systems throughout the switched network can precisely synchronize to the source clock.

Abstract: A system and method for granular redundant multithreading in a high integrity multicore processing environment (MCPE) generates redundant critical application threads incorporating executable instructions and input data relevant to a critical process when a user application running on a homogenous core of the MCPE encounters the critical process and issues a system call. The critical application threads are forked to different processing cores environments for execution, and the result sets of each executed critical application threads are forked to different cores for cross-comparison (different from the cores on which the result sets were generated). The result sets are cross-checked to the desired degree of integrity (e.g., consensus agreement or majority vote of all comparing cores) and the hypervisor returns the execution returned to the calling user application with the final result set (or with a fault, if the evaluation was unsuccessful and the desired level of agreement not reached).

Abstract: An improved AFDX switch, as described herein, can include an embedded integrity monitoring module that is functionally fault-independent of the switching module or other components of the AFDX switch. The integrity monitoring module can include a delay monitoring module for monitoring delays of data packets within the AFDX switch and/or a routing module for monitoring or detecting data packets routing errors or failures. The delay monitoring module can assign a timestamp to a data frame at arrival to the AFDX switch, determine a time delay of the data frame within the AFDX switch based on the timestamp, and compare the time delay to a threshold value to detect erroneous time delays. The routing monitoring module can compare the input port and/or the output port at which the data frame arrives while in the AFDX switch to the corresponding preassigned input port or output port to detect routing failures.

Abstract: Transparently executing applications among cores in a multi-processor system includes monitoring elements associated with each processor which align execution of threads within corresponding cores of the processors. Alignment is accomplished by monitoring system resource utilization by each core, comparing process counters associated with corresponding cores, and comparing data sets in and out during application frame switching. In a further aspect, inputs are coordinated by a synchronization element. Likewise, outputs for corresponding cores are compared to ensure no corrupted data is propagated.

Abstract: A high-integrity multi-core heterogeneous processing environment and methods for high integrity computing on multi-core heterogeneous processing environments are disclosed. A multi-core heterogeneous processing environment may include an application processor with one or more processing cores and an integrity tester for executing integrity kernels on the application processor. The multi-core heterogeneous processing environment may further include an integrity processor having a different architecture than the application processor and an integrity manager operating on the integrity processor. The integrity manager may dynamically generate integrity kernels to test the functionality of the application processor prior to and/or subsequent to the execution of critical programs on the application processor.

Abstract: A system and related method for I/O synchronization in a high integrity multi-core processing environment (MCPE) incorporates logical computing units (LCU) of two or more homogeneous processing cores, each core running a guest operating system (GOS) and user applications such that the homogeneous cores concurrently generate the same output data (which the GOS loads to an I/O synchronization engine (IOSE)) or receive the same output data from the IOSE. The IOSE verifies data integrity by comparing the concurrently received datasets and selects a verified dataset for routing to other cores or externally to the MCPE. The IOSE receives and atomically replicates input data for synchronous transfer to, and consumption by, the user applications running on the cores of the LCU.