Internet of Things is a large network of interconnected ”things”. IoT refers to the exchange of data and information from real world devices to the Internet. IoT technology will enable breakthrough applications in several areas such as e-Health, smart cities, transportation and industry, and includes multiple technologies, cloud computing, communication, etc. IoT reveals not only the possibilities of high efficiency and low cost, but also scalability. On the other hand, security issues exist and are a major concern for researchers. This article is a systematic literature review (SLR) where show the most basic and common architecture proposed for IoT with a security analysis of each layer. This SLR is also made to present IoT security solutions, as well as a comparison of these solutions. Finally we will present future research directions.