service providers physically secure the IT hardware (servers, routers, cables etc.) against unauthorized access, interference, theft, fires, floods etc. and ensure that essential supplies (such as electricity) are sufficiently robust to minimize the possibility of disruption. This is normally achieved by serving cloud applications from professionally specified, designed, constructed, managed, monitored and maintained data centers. Personnel security Various information security concerns relating to the IT and other professionals associated with cloud services are typically handled through pre-, para- and post-employment activities such as security screening potential recruits, security awareness and training programs, and proactive. Privacy Providers ensure that all critical data (credit card numbers, for example) are masked or encrypted and that only authorized users have access to data in its entirety. Moreover, digital identities and credentials must be protected as should any data that the provider collects or produces about customer activity in the cloud. Penetration testing Penetration testing is the process of performing offensive security tests on a system, service, or computer network to find security weaknesses in it. Since the cloud is a shared environment with other customers or tenants, following penetration testing rules of engagement step-by-step is a mandatory requirement. Scanning and penetration testing from inside or outside the cloud should be authorized by the cloud provider. Violation of acceptable use policies can lead to termination of the service. Cloud vulnerability and penetration testing Scanning the cloud from outside and inside using free or commercial products is crucial because without a hardened environment your service is considered a soft target. Virtual servers should be hardened just like a physical server against data leakage, malware, and exploited vulnerabilities. "Data loss or leakage represents 24.6% and cloud-related malware 3.4% of threats causing cloud outages” Scanning and penetration testing from inside or outside the cloud must be authorized by the cloud provider. Since the cloud is a shared environment with other customers or tenants, following penetration testing rules of engagement step-by-step is a mandatory requirement. Violation of acceptable use policies can lead to the termination of the service. Some key terminology to grasp when discussing penetration testing is the difference between application and network layer testing. Understanding what is asked of you as the tester is sometimes the most important step in the process. The network-layer testing refers to testing that includes internal/external connections as well as the interconnected systems throughout the local network. Oftentimes, social engineering attacks are