%A Canh Minh Nguyen %A Duc Tan Tran %A Quang Trung Hoang %A Trung Ninh Bui %A Quoc Anh Gian %A Bhanu Prakash Kolla %A El-Rabaie Sayed %T Cross-Layer Design for Wireless Sensor Networks Using Cooja Tool in Contiki Operating System %X RPL is a routing protocol for low power and lossy networks (LLNs) or wire-less sensor networks (WSNs). In recent years, this protocol is considered more and more by research communities in the world because of its poten-tial benefits on the internet of things (IoT) applications. However, this pro-tocol still has some drawbacks related to balancing packet traffic and saving consumed energy of sensor nodes which needs to be improved. In this pa-per, we propose an enhanced routing protocol based on ContikiMAC and RPL protocols in the Contiki operating system approached on the cross-layer design, named CL-RPL. By analyzing and evaluating the affection of the proposed protocol using the Cooja tool in the Contiki operating system, we estimated the consumed battery energy of sensor nodes in WSNs and proved that our CL-RPL protocol can support the system performances bet-ter than the previous original RPL protocol in terms of network lifetime and packet delivery ratio. %C Swinburne Innovation Space, 80 Duy Tan, Cau Giay, Hanoi (Vietnam) %L SisLab4761