Cloud Computing Evolution
                     CLOUD COMPUTCING EVOLUTION
Introduction
• Cloud computing is all about renting computing services. This idea first 
came in the 1950s. In making cloud computing what it is today, five 
technologies played a vital role. 
• These are distributed systems and its peripherals, virtualization, web 2.0, 
service orientation, and utility computing.
Source: www.geeksforgeeks.org
Distributed Systems
• Distributed systems possess characteristics such as scalability, 
concurrency, continuous availability, heterogeneity, and independence in 
failures. 
• But the main problem with this system was that all the systems were 
required to be present at the same geographical location.
Source: www.geeksforgeeks.org
Mainframe computing
• Mainframes which first came into existence in 1951 are highly powerful 
and reliable computing machines. These are responsible for handling large 
data such as massive input-output operations.
Source: www.geeksforgeeks.org
Cluster computing
• In 1980s, cluster computing came as an alternative to mainframe 
computing. Each machine in the cluster was connected to each other by a 
network with high bandwidth. These were way cheaper than those 
mainframe systems. 
Source: www.geeksforgeeks.org
Grid computing
• In 1990s, the concept of grid computing was introduced. It means that 
different systems were placed at entirely different geographical locations 
and these all were connected via the internet. 
• These systems belonged to different organizations and thus the grid 
consisted of heterogeneous nodes.
Source: www.geeksforgeeks.org
Virtualization
• It was introduced nearly 40 years back. It refers to the process of creating 
a virtual layer over the hardware which allows the user to run multiple 
instances simultaneously on the hardware. It is a key technology used in 
cloud computing.
Source: www.geeksforgeeks.org
Web 2.0
• It is the interface through which the cloud computing services interact with 
the clients. It is because of Web 2.0 that we have interactive and dynamic 
web pages. It also increases flexibility among web pages. 
Source: www.geeksforgeeks.org
Service orientation
• It acts as a reference model for cloud computing. It supports low-cost, 
flexible, and evolvable applications. Two important concepts were 
introduced in this computing model. 
• These were Quality of Service (QoS) which also includes the SLA (Service 
Level Agreement) and Software as a Service (SaaS).
Source: www.geeksforgeeks.org
Utility computing
• It is a computing model that defines service provisioning techniques for 
services such as compute services along with other major services such as 
storage, infrastructure, etc which are provisioned on a pay-per-use basis.
Source: www.geeksforgeeks.org
Cloud Computing
• In 1999, Salesforce.com started delivering of applications to users using a simple website. The 
applications were delivered to enterprises over the Internet, and this way the dream of computing 
sold as utility were true.
• In 2002, Amazon started Amazon Web Services, providing services like storage, computation and 
even human intelligence. In 2009, Google Apps also started to provide cloud computing enterprise 
applications.
Source: www.javatpoint.com