The object of the invention is in particular a device for execution of applications (510) in an aircraft information-processing system (500), permitting the simultaneous execution of at least two distinct applications, the said information-processing system comprising shared calculation and storage resources. The device comprises software segregation means capable of creating at least two distinct information-processing environments (505), a partition of the said calculation and storage resources being allocated to each of the said at least two environments in such a way that the execution of one of the said at least two applications in one of the said at least two environments does not have any effect on the execution of the other of the said at least two applications executed in the other of the said at least two environments. Another object of the invention is a method for employing such a device.