Enforcing security within IoT environments is challenging issue with multiple decisions to make: what kind of cryptography (shared secret or PKI) to use, does the crypto algorithms increase output payload size, are algorithms efficient enough to execute in devices with few MHz of processing power. Bootstrapping a new IoT device in your home ecosystem by maintaining a decent balance between security and usability will be key for wide adoption of IoT. This talk will cover the security architecture of Iotivity by providing an overview of provisioning, authentication/encryption and access control mechanisms employed in Iotivity.