I. Introduction
INFRASTRUCTURE as a service (IaaS) cloud systems offer computational infrastructure services to multiple clients by means of virtual machines (VMs). The recent surge in the popularity of IaaS cloud systems can be attributed to the on-demand availability of computing resources such as processor cores, memory, disks, etc., packages as VMs that are billed on use [1], [2]. At times, the service requirements are such that not all VMs can be hosted on a single machine. Incoming task requests may demand VMs of different capacities as well. In this scenario, coalitions of machines need to be formed to service a particular request [3]. In particular, in IaaS systems, VMs are available in specific configurations that are further customized by clients by adding operating systems and software on top [2]. Coalitions of preconfigured VMs created before the arrival of requests address scalability concerns to a large extent, in addition to shortening response times.