Cloud Testing Challenges Cloud testing techniques are still in their infancy. Several challenges are associated as below (Jain & Malhotra, 2013; Gopalakrishnan, Prakash & Ramadoss, May 2012): Cloud Service Model: With a variety of service models and having customers from multiple domains, it is very difficult for the testing team to generate an optimal test matrix. For each service model, the subscriber has access to different sets of system components and therefore has different use cases for testing availability, security and performance. For example, in the case of SaaS, the CSP is responsible for the performance experienced by the end user, while in PaaS, the CSP is only responsible for the performance of the environment and infrastructure. Furthermore, different areas of activity carry different risks and therefore different acceptance matrices. For example, for a medical company, data security is a major concern, for a travel agency, service availability is a major concern. Security Challenges: Information security takes on a whole new dimension when it goes beyond the customer's scope. location internally and becomes part of external domain space shared with multiple clients. Since the cloud supports multi-tenancy, the testing team must perform a comprehensive set of security tests to ensure that data is protected not only from Internet attacks, but also from those of others clients sharing the same cloud. Data security must address aspects such as data access, storage, retention and integrity policies. This can be done by performing data access and multiple privilege testing. The challenge is how to simulate a test environment where any change in another customer's load can change the outcome. Running a scenario with multiple tenants is useful to ensure there are no vulnerabilities. Along with multi-tenant testing, other testing also requires...... middle of paper ...... difficult for a tester to determine the impact of an updated interface on other interfaces and integrated system. This testing can be done by performing backward interface compatibility testing. Again, automated testing of regression cases is a great help in successfully testing changes. Frequent release of feature-rich applications: SaaS provider frequently releases feature-rich applications to compete with market demands. To ensure that new features, the application communicates correctly with other interfaces and that all features work correctly, the tester must perform end-to-end testing. Performing end-to-end testing is a tedious and difficult task. This challenge can be addressed by creating an automated test library to test SaaS application upgrades. Tests should measure the impact on functional and non-functional aspects of the application..