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Space satellite with its solar panels extended

Secure the success of next-generation space missions with LithOS

LithOS is a real-time guest operating system specially designed and certified for XtratuM hypervisor. LithOS follows the ARINC-653 APEX standard, a software specification which ensures exclusive access to physical and temporal resources in partitioned real-time embedded systems.

Choosing LithOS as your guest OS

LithOS uses the services provided by XtratuM to provide the additional mechanisms required to develop applications with features such as:

Implementation of the process concept presented in the ARINC-653 standard

Support of multiple concurrent processes in the same partition

Communication between processes

Implementation of the process scheduling

About ARINC-653 Standard

ARINC-653 specification defines an APplication EXecutive (APEX) for space and time partitioning that may be used wherever multiple applications need to share a single processor and memory, in order to ensure an exclusive access of physical and temporal resources to the applications, while sharing computer resources, and guarantee that one application cannot bring down another in the event of application failure.

In the case of embedded systems, particularly avionics systems, ARINC 653 standard defines a partitioning scheme. Although this standard was not designed to describe how a hypervisor must operate, some parts of the model are quite close to the functionality provided by a hypervisor.

The XtratuM API and internal operations resemble the ARINC-653 standard, but XtratuM is not an ARINC-653 compliant system.

Space satellite with its solar panels extended