  With more and more devices becoming connectable to the internet, the number
of services but also a lot of threats increases dramatically. Security is often
a secondary matter behind functionality and comfort, but the problem has
already been recognized. Still, with many IoT devices being deployed already,
security will come step-by-step and through updates, patches and new versions
of apps and IoT software. While these updates can be safely retrieved from app
stores, the problems kick in via jailbroken devices and with the variety of
untrusted sources arising on the internet. Since hacking is typically a
community effort? these days, security could be a community goal too. The
challenges are manifold, and one reason for weak or absent security on IoT
devices is their weak computational power. In this chapter, we discuss a
community based security mechanism in which devices mutually aid each other in
secure software management. We discuss game-theoretic methods of community
formation and light-weight cryptographic means to accomplish authentic software
deployment inside the IoT device community.
