The Constrained Application Protocol (CoAP) is the product of the IETF (RFC7228). The IETF Constrained RESTful Environments (CoRE) working group created the first draft of the protocol in June 2014 but had worked for several years on its creation. It is specifically intended as a communication protocol for constrained devices. The core protocol is now based on RFC7252. The protocol is unique as it is first tailored for machine-to-machine (M2M) communication between edge nodes. It also supports mapping to HTTP through the use of proxies. This HTTP mapping is the on-board facility to get data across the internet.  

CoAP is excellent at providing a similar and easy structure of resource addressing familiar to anyone with experience of using the web but with reduced resources and bandwidth demands. A study performed by Colitti et. al demonstrated the efficiency of CoAP over standard HTTP (Colitti, Walter & Steenhaut, Kris & De, Niccolò. (2017). Integrating Wireless Sensor Networks with the Web). CoAP provides a similar functionality with significantly less overhead and power requirements.

Additionally, some implementations of CoAP perform up to 64x better than HTTP equivalents on similar hardware.