Resource Observation in WSN-based Constrained Networks

As we move slowly to a paradigm where a large number of machines will interact with each other without the need for human intervention, we begin to realize that we need a standard way to enable communication between these machines. Additionally, since a lot of good work has already been done in the past to setup the Internet and the IP networks, it makes sense to follow the lead and try to leverage the already existing infrastructure and build on top of it. To standardize a communication methodology for machines to independently exchange information with each other, keeping in mind that we want to build on and leverage existing knowledge and infrastructure. The Internet Engineering Task Force created a working group called Constrained RESTful Environment Group (or CoRE) group. This group was assigned the task to define a mechanism using which a large number of small, resource constrained, low power devices can communicate over low-power lossy networks. This group defined a set of specifications that is known today collectively as – Constrained Application Protocol or CoAP in short. The objective of this paper is to provide an overview of CoAP protocol and observing resource, similar to http, in the Internet of things (IoT) and wireless sensor networks (WSNs).