3. The five essential characteristics of Cloud Computing

The use of remote resources is not new. Time sharing – shared use of a computer in Basic language first appeared in 1966. At the time, it was referred to as the "computing socket" next to the power socket. By the early 1970s, "service bureau" or "contract processing" activities were sharing processes such as payroll or invoicing on shared infrastructures, often on a pay-as-you-go basis. More recently, under the name outsourcing, remote hosting and operation of corporate applications have become widespread. These activities had not changed systems architecture. The gains came from pooling premises and human and technical resources specialized in the operation of existing systems and applications.

The Cloud Computing model is characterized by the following five key features.