The National Institute of Standards and Technology (NIST) defines the fundamental of cloud computing as a concept for delivering a shared pool of configurable computing resources, which can be provisioned and released with minimum management effort and service provider interaction. Also, it enables convenient, on-demand network access to these resources [1]. Most companies today are increasingly interested in taking advantage of the flexibility and choice of multiple cloud offerings and adopt more than one cloud to make the best use of a variety of services [2]. Multi-cloud is a combination of multiple public clouds and private clouds [3]. Its goal is to enable cloud users to avoid vendor blocking and make the best use of multiple cloud services that can cooperate and interact with each other [4]. In 2018, the International Data Corporation predicted that more than 85% of IT companies would invest

The growth of local data annually implies extra charges for the customers, which makes their business slowing down. Cloud computing paradigm comes with new technologies that offer a very economic and cost-effective solution, but the organizations are slow in accepting it due to security issues and challenges associated with it. Security is one of the major issues which hamper the growth of cloud and it is highly crucial to protect the sensitive data and systems in the cloud setting in order to ensure the privacy of its users. This work explores the new directions in cloud computing security, while highlighting the correct selection of these fundamental technologies from cryptographic point of view.

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