Cloud Security Issue and Challenges

In past three decades, the world of computation has changed from centralized (client-server not web-based) todistributed systems and now we are getting back to the virtual centralization (Cloud Computing). Location of data and processes makes the difference in the realm of computation. On one hand, an individual has full control on data and processes in his/her computer. On the other hand, we have the cloud computing wherein, the service and data maintenance is provided by some vendor which Leaves the client/customer unaware of where the processes are running or where the data is stored. So, logically speaking, the client has no control over it. The Cloud computing uses the internet as the communication Media. When we look at the security of data in the cloud Computing, the vendor has to provide some assurance in Service level agreements (SLA) to convince the customer on security issues. Organizations use cloud computing as a service infrastructure; critically like to examine the security and confidentiality issues for their business critical insensitive applications. Yet, guaranteeing the security of corporate data in the "cloud" is difficult, if not impossible, as they provide different services like Software as a service (SaaS), Platform as a service (PaaS), and Infrastructure as a service (IaaS). Each service has their own security issues. So the SLA describes different levels of security and their complexity to make the customer understand the security policies that are being implemented. There has to be a standardized way to prepare the SLA irrespective to the providers. This can help some of the enterprises to look forward in using the cloud services. In this paper, we put forward some security issues that have to be included in SLA. Keywords: Cloud Computing, Service Level Agreement (SLA), Software as a Service (SaaS), Cloud computing Security