Investigating the CoAP Congestion Control Strategies for 6TiSCH-Based IoT Networks

The Constrained Application Protocol (CoAP) is a RESTful protocol standardized by the IETF and widely used for IoT applications. CoAP includes default congestion control algorithm to ensure efficient operation under high traffic conditions. Other algorithms have been proposed evaluated in literature, including very popular CoCoA algorithm. All these assume that underlying wireless communication regulated through 802.15.4 CSMA-CA protocol. Today, many systems are based on 6TiSCH architecture that, instead, leverages TSCH (Time Slotted Channel Hopping) mode of IEEE 802.15.4, i.e., synchronous time-slotted access In this paper we investigate, simulation, suitability existing congestion-control architecture. Our results show performance considered strongly influenced Scheduling Function allocate resources nodes. addition, our analysis emphasizes does not provide significant advantage over networks. We investigate motivations such behavior propose an optimized version CoCoA, namely 6CoCoA, specifically tailored 6CoCoA able up 15% improvement Transaction Delivery Ratio 25% reduction end-to-end Delay, when network congested.