| SaaS (Software as a Service) is a new method that uses the Cloud to deliver service to the users. Since its inception, researchers and practitioners were attracted by the development, security, and networking aspects and problems of the SaaS. However, equivalent focus or attraction was not given to measuring and/or analyzing the quality attributes of the SaaS. In this dissertation my work is devoted to investigating and developing methods to measure, analyze, and improve SaaS quality.;One of the major contributors to software quality improvement is defect analysis. Current work in this area does not consider multi-tenancy or isolation, which makes it inappropriate to implement on a SaaS. This dissertation proposes a defect analysis model by adopting the ODC (Orthogonal Defect Classification) concept to the Cloud.;Another contributor to the quality of software is reliability analysis. Reliability is one of the most important attributes of quality for SaaS. In this dissertation a method for measuring and predicting the reliability of SaaS through analyzing web server logs is developed. The observed failures in conjunction with the workload are analyzed for reliability assessment and prediction. The workload is measured by counting the number of system invocations and the time taken for each invocation. Operational reliability is measured using IDRM (Input domain reliability modeling). Potential reliability change or growth is estimated through SRGM (Software reliability growth modeling). |
