This dissertation describes a deterministic convergecast algorithm implemented in a 6TiSCH protocol stack. Convergecast is a method of passing messages in which all nodes in a network transmit messages to a root node. The developed algorithm uses a scheduling technique called dilution, to elect leaders and to build a convergecast tree. This technique is based on the concept that nodes distant from each other (by at least a certain distance) can transmit simultaneously, without interference in communication or loss of messages in their proximity (within a certain range). To schedule these messages, the execution synchroniicty provided by the TSCH protocol is used. This project was developed for the Contiki-NG operating system and therefore uses a real protocol stack. The results of the simulations yielded a practically perfect performance in the ability of the convergecast algorithm to avoid message losses, even with all nodes transmitting at every possible opportunity, and maintaining a message transmission rate, depending on the network density, above 40 messages per minute for each node.