(Received: 13-Jun.-2020, Revised: 9-Aug.-2020 , Accepted: 9-Sep.-2020)
In this era of communication and networking technology, Internet of Things adds to the existing technological era and brings revolution to the Information Technology world. Internet of Things consists of interconnected devices which may be digital, physical or mechanical devices equipped with unique identifiers and having the capability to transmit the sensed information to other devices autonomously. Internet of Things is recognized as being composed of resource constraint devices in terms of processing competency, storage capacity and power resources. To cope up these constraints, existing computing technology known as cloud computing can be used to facilitate the Internet of Things system by offloading its processing and storage requirements. In this paper, we have provided the necessity and benefits of Cloud and IoT integration. Further, the paper has identified several research issues that arise due to Cloud-IoT integration. Among the several research issues, it was observed that security and privacy concerns are pivotal in Cloud-IoT integration and need to be addressed to make the integration successful. The core security and privacy threats have been identified and the existing security mechanisms have also been researched in this paper. The paper also highlights open security and privacy research issues in the Cloud-IoT paradigm. This paper can act as a baseline for the research that is needed in the area of security and privacy issues in the Cloud-IoT or Cloud of Things paradigm.

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