Cloud computing, being the most recent emerging paradigm, is a technological advancement that aims at turning the vision of computing utilities into a reality. Simply, it is an approach of making technology available to the users, by the usage of Internet servers for data storage and processing. More specifically, cloud computing offers users benefits such as scalability, availability, reliability and global accessibility. Being a radical mechanism, the major obstacles for massive adoption of cloud computing are security, trust and privacy issues. With some defensive procedures like using a combination of methods that include encryption, authentication, and authorization, users are still concerned about the risks associated with their stored data. In this survey, many efficient and secured claiming techniques are investigated for end users to access the data stored in the cloud. The focus is here much on securing the data residing in cloud and privacy in accessing them. The study will throw lights upon keyword search, indexing, file splitting, encryption, and multi-cloud. Further, various methodologies in the existing system and performance of algorithms together with their pros and cons are discussed. Also, cloud security challenges, privacy and communication issues are considered and addressed here.

Keyword Search, Secure Data, Data Privacy, Cloud Computing, Splitting Techniques, Encryption

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