In machine to machine (M2M) communication, the major idea is enabling various devices to be controlled and connected remotely    with low-power, reliable, low-cost, and scalable technologies. Through service and resource discovery (SD) mechanisms, devices can discover all the obtainable services. This paper gives an extensive study and comparison of the various service and resource discovery mechanisms proposed and implemented for Internet of Things (IoT). Also, this paper introduces a road map for researchers working in the field of IoT to choose the best mechanism to use in developing their proposed protocols in different areas of IoT.

Internetofthings,context-awareservices,cooperative communication, ubiquitous computing, wireless sensor networks.