<P>Background: The cloud computing is the modern trend in high-performance computing.
Cloud computing becomes very popular due to its characteristic of available anywhere, elasticity,
ease of use, cost-effectiveness, etc. Though the cloud grants various benefits, it has associated issues
and challenges to prevent the organizations to adopt the cloud.
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Objective: The objective of this paper is to cover the several perspectives of Cloud Computing. This
includes a basic definition of cloud, classification of the cloud based on Delivery and Deployment
Model. The broad classification of the issues and challenges faced by the organization to adopt the
cloud computing model are explored. Examples for the broad classification are Data Related issues in
the cloud, Service availability related issues in cloud, etc. The detailed sub-classifications of each of
the issues and challenges discussed. The example sub-classification of the Data Related issues in cloud
shall be further classified into Data Security issues, Data Integrity issue, Data location issue, Multitenancy
issues, etc. This paper also covers the typical problem of vendor lock-in issue. This article
analyzed and described the various possible unique insider attacks in the cloud environment.
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Results: The guideline and recommendations for the different issues and challenges are discussed.
The most importantly the potential research areas in the cloud domain are explored.
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Conclusion: This paper discussed the details on cloud computing, classifications and the several issues
and challenges faced in adopting the cloud. The guideline and recommendations for issues and
challenges are covered. The potential research areas in the cloud domain are captured. This helps
the researchers, academicians and industries to focus and address the current challenges faced by
the customers.</P>
Cross-VM Network Channel Attacks and Countermeasures within Cloud Computing Environments
