Abstract
Cloud computing is particularly well suited for applications with a variable workload such as, for example, complex-event processing (CEP) applications. Since these applications experience variability in utilization of resources, they are calling for an infrastructure that can dynamically scale according to the application demand. Scalability is one of the major advantages offered by IaaS (Infrastructure-as-a-Service) clouds. This gives rise to the idea to deploy CEP applications into IaaS clouds. But an IaaS cloud requires that CEP applications should be specifically designed for the cloud to benefit from its scalability. Thus, the problem is how to dynamically scale legacy and existing CEP applications (which have been around for years) with little or no changes to the application code.