Cloud computing has improved computation’s efficiency while reducing its cost for users.
A typical data center for cloud computing consists of tens to hundreds of thousands of servers and comprises hundreds to thousands of hierarchically connected switches.
By sharing computing resources through services such as software as a service (SaaS), users can amortize the cost of hardware and software.
To ease system upgrades and maintenance, virtual machines (VMs) are often employed to provide services, and their migration across the physical hosts results in higher resource utilization.