It is very important to take security and privacy into account when designing and using cloud services. In this paper security in cloud computing was elaborated in a way that covers security issues/concerns and challenges , security standards and security management models and Digital Signature with RSA encryption algorithm to enhance Data Security in Cloud . –Security issues/concerns indicate potential problems which might arise. –Security standards offer some kind of security templates which cloud service providers (CSP) could obey. The most promising standard for the future would be OVF format which promises creation of new business models that will allow companies to sell a single product on premises, on demand, or in a hybrid deployment model. –Security management models offer recommendations based on security Standards best practices –Digital signature with RSA algorithm, to encrypting the data while we are transferring it over the network. .A digital signature or digital signature scheme is a mathematical scheme for demonstrating the authenticity of a digital message or document.

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Cloud Computing Risk management RSA algorithm