technology which is coming under the Ubiquitous Computing. Cloud services are delivered from the data centers located throughout the world. Cloud services and Cloud issues and challenges are described in this paper. Cloud Computing is a novice technology and it is very familiar among IT users for providing its large variety resources among its consumers. The authors, discussed various load balancing and scheduling techniques to improve QoS (Quality of Service] in cloud. This paper would benefit researchers to explore the research areas in cloud computing.
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