Casablanca INT is a leading Czech provider of internet, data and voice services. Their challenge is building a virtual data center providing advanced functions of a public cloud Infrastructure as a Service to customers (IaaS). They chose VMware to overcome this challenge. They have implemented VMware vSphere Enterprise Plus, VMware vCenter and others. The results of implementing VMware were sharp decrease of internal costs for operation and management, powerful infrastructure replacing an entire housing hall, unlimited computing power for ICT services, internet and on-line projects and applications and fully automated environment with nonstop access and option of change in configuration or implementation of a new machine.