The key aspects of IT infrastructure, hardware, facilities, and administration have traditionally been the domain of IT departments within each company. Dedicated personnel install and configure servers, routers, firewalls, and other devices in support of their respective employers. This equipment requires dedicated housing as well as environmental controls, emergency power, and security systems to keep it functioning properly. Finally, every company allocates additional space where IT personnel work to support the infrastructure that is in place.
Every aspect of IT infrastructure has evolved on its own, yet - until now - has not moved toward integration. For example, a company purchases software it needs and then purchases a server to run it. If data storage is necessary for files or databases, disk arrays and hard drives are added into the mix to accommodate the needs of the company. A local network is maintained to provide employees access to IT resources, and high speed internet connectivity for voice and data is added to the company account as necessary. Practically speaking, each IT system has its own management system, with some systems requiring the addition of a specialized worker to the staff.
Infrastructure as a service takes the traditional components of IT infrastructure, takes them off site, and offers them in one unified, scalable package to companies who can manage them through one management interface.
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