Abstract

The Time Slotted Channel Hopping (TSCH) mode of the standard IEEE 802.15.4 provides Medium Access Control (MAC) for most Low power and Lossy Network (LLN) applications in the Internet of Things (IoT). TSCH uses a synchronized schedule with frequency diversity to allow flexible, reliable and resilient communication. The standard defines an association algorithm to allow nodes to autonomously form the network. The time required to create the network can be long, which consumes valuable energy given that nodes keep their radios on when trying to associate. In this letter, we propose a theoretical model to estimate the time required for a node to associate to one single synchronizer. This model extends and complements earlier mathematical models. Its results comply with outcomes from extensive simulation studies. This makes the proposed model a valuable tool to further investigate the time needed to form TSCH-based LLN networks.