In this paper we set out to have a comprehensive view on the embedded security for IoT system and propose a hardware/software design methodology that can help designers and developers to deliver more secure devices. This paper is structured as follows: section 2 talks about the IoT scenario, highlighting the devices involved in the network. Section 3 describes the different types of attacks on IoT systems. Section 4 illustrates the security requirement for IoT. Section 5 raises some issues and challenges for security of IoT systems. Section 6 highlights the related work. Section 7 focuses on the embedded security building blocks for IoT. Section 8 proposes a framework for embedded