Abstract Robot Operating System (ROS) is a middleware for connecting different components of robots. However, its use is becoming more popular in other domains such as in the automotive sector where initial prototypes have been customized and deployed in cars for demonstrating different functional purposes. Nevertheless, ROS has not been yet tested enough to be used in secure and safety environments. For example, in order to strengthen our ROS architecture, we have encrypted the messages within it. Therefore, this paper analyses the impact of Advanced Encryption Standard (AES) encryption mechanism and the functional safety of our prototype. In this sense, we are considering encrypting messages and we assess the timing constraints, as suggested by the ISO 26262, required for assuring a secure communication between components.

This paper reports the results of a study on the impact of a type of side effect (SE) upon program comprehension. We applied a crossover design on different tests involving fragments of C code that include increment and decrement operators. Each test had an SE version and a side-effect-free counterpart. The variables measured in the treatments were the number of correct answers and the time spent in answering. The results show that the side-effect operators considered significantly reduce performance in comprehension-related tasks, providing empirical justification for the belief that side effects are harmful.

Side-effects are widely believed to impede program comprehension and have a detrimental effect upon software maintenance. This paper introduces an algorithm for side-effect removal which splits the side-effects into their pure expression meaning and their state-changing meaning. Symbolic execution is used to determine the expression meaning, while transformation is used to place the state-changing part in a suitable location in a transformed version of the program. This creates a program which is semantically equivalent to the original but guaranteed to be free from side-effects. The paper also reports the results of an empirical study which demonstrates that the application of the algorithm causes a significant improvement in program comprehension.