The Internet of Things frameworks can improve quality and performance of controlled system but also leading the system to be weaker from the cyber security point of view: new devices can be used to exploit system vulnerabilities with malicious intentions. In this paper the effect of a cyber-attack in a modern all-electric ship Integrated Power System is investigated and an alternative paradigm is exploited with a view to enhancing the system security and reliability. The need for security by design has become crucial but it is not enough to prevent all the cyber-attacks and so the dependability theory approach is considered in order to avoid the undesired system failures.