  The Internet of Things (IoT) is becoming an integral part of our modern lives
as we converge towards a world surrounded by ubiquitous connectivity. The
inherent complexity presented by the vast IoT ecosystem ends up in an
insufficient understanding of individual system components and their
interactions, leading to numerous security challenges. In order to create a
secure IoT platform from the ground up, there is a need for a unifying
operating system (OS) that can act as a cornerstone regulating the development
of stable and secure solutions. In this paper, we present a classification of
the security challenges stemming from the manifold aspects of IoT development.
We also specify security requirements to direct the secure development of an
unifying IoT OS to resolve many of those ensuing challenges. Survey of several
modern IoT OSs confirm that while the developers of the OSs have taken many
alternative approaches to implement security, we are far from engineering an
adequately secure and unified architecture. More broadly, the study presented
in this paper can help address the growing need for a secure and unified
platform to base IoT development on and assure the safe, secure, and reliable
operation of IoT in critical domains.
