The consequences of security problems are increasingly serious. These problems can now lead to personal injury, prolonged downtime and irreparable damage to capital goods. To achieve this, systems require end-to-end security solutions that cover the layers of connectivity, furthermore, guarantee the privatization and protection of data circulated via networks. In this paper, we will give a definition to the Internet of things, try to dissect its architecture (protocols, layers, entities …), thus giving a state of the art of security in the field of internet of things (Faults detected in each layer …), finally, mention the solutions proposed until now to help researchers start their researches on internet of things security subject.