Internet of Things (IoT) is characterized by heterogeneous technologies, which concur to
the provisioning of innovative services in various application domains. In this scenario,
the satisfaction of security and privacy requirements plays a fundamental role. Such
requirements include data confidentiality and authentication, access control within the
IoT network, privacy and trust among users and things, and the enforcement of security
and privacy policies. Traditional security countermeasures cannot be directly applied to
IoT technologies due to the different standards and communication stacks involved.
Moreover, the high number of interconnected devices arises scalability issues; therefore
a flexible infrastructure is needed able to deal with security threats in such a dynamic environment.
In this survey we present the main research challenges and the existing solutions
in the field of IoT security, identifying open issues, and suggesting some hints for future
research.