Cloud Computing has been a one-key, cost-effective solution for many small I.T industries from past few decades in terms of storage, computation etc. It provides different kinds of services and infrastructural support. While cloud makes these services more appealing, it also brings some critical security threats to the cloud service users as well as to the cloud service providers. In this paper authors have tried to identify major security threats faced by different models of cloud in current day scenario and providing with some suitable solutions addressing those threats like One-time password, Homomorphic encryption technique, Access control and Data Recovery mechanism in different cloud deployment models.

Third Party Auditor, One-time password, Homomorphic encryption technique, Access control and Data Recovery mechanism, Cloud Service User (CSU), Cloud Service Provider(CSP).

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