IoT security is more challenging than cyber security because of two key factors: the enormous attack surface presented by the anticipated billions of IoT devices, and the increased vulnerability of many of those devices. Device manufacturers need to employ traditional cyber security techniques—including a defense-in-depth approach with multiple complementary security technologies—in their devices, then adapt those techniques for the unique aspects of IoT devices, and finally incorporate other device-specific countermeasures where necessary to provide comprehensive and adaptive IoT security.