Time synchronization protocol for 6LoWPAN

The future is seen as place where all perceivable objects will have a layer of digital connectivity. The concept of Internet of Things involves connecting devices embedded with microcontrollers such as sensors to IP based networks. 6LoWPAN is a new set of standard for IPv6 connectivity over such low power wireless personal area networks. Time synchronization is essential in 6LoWPAN to time-align the data send by the different sensors. The other advantage of time synchronization will be to realize a perfect wake up scheme of the sensor nodes making the most of its limited power supply. Although time-synchronization has been well studied for traditional networks and to some extent in wireless sensor network, it has not been implemented for 6LoWPANs. In this paper, we propose a time synchronization protocol for 6LoWPAN. The fully functional device (FFD) does a pairwise synchronization with other synchronized FFD or the edge router. The Reduced Functional Devices (RFD) are synchronized using flooding technique.