Nowadays enterprises need to maintain plenty of applications accessing by millions of users all over the world. Maintaining their own infrastructure, managing software requirements and handling excessive internet traffic is difficult. This makes them to move towards cloud computing. Cloud computing is a service provisioning technique, where customers can rent any resources like hardware, software, or platform to develop an application. Customers need to pay only for how much the resources were

more »

... onsumed, can dynamically increase or decrease the resource capacity as needed. Because customers are paying for the services, they expect quality of service from the provider. Providing a quality of service and attracting the customers is a challenging issue for the providers. If not, customers will move towards other cloud providers. Thus Service Level Agreement (SLA) is made between providers and customers that include service quality, resources capability, scalability, obligations and consequences in case of violations. Satisfying SLA is very important and a challenging issue. In this paper, different framework and techniques proposed by the different authors for providing a quality of service and maintaining SLA are discussed.