Overview of Cloud Computing

Tatiana Malyuta, Ph.D.Associate Professor

Computer Systems Technology Department

Two Sides of Cloud Computing•A new business model•A number of new technologies that •Enable this business model •Address the challenges of data and information "tsunami" by taking scalability, performance, and pace of innovation to new levels

IT Business Model – Before •The traditional IT business model involves selling/purchasing hardware, software and services: servers to run applications, disk drives to store data, networks and Internet to access the applications and data, and facilities to host the data center

Cloud Computing Business Model

• In recent years, the "do-it-all-yourself" approach, which often requires high up-front capital expenditures and may not result in long-run efficient utilization of the acquired resources, has been replaced with a "buy-part-of-it-as-a-service" approach, where the "part" includes:• infrastructure (Infrastructure as a Service - IaaS)• platform (Platform and a Service - PaaS) • software (Software as a Service - SaaS)

• IT providers and consumers are trying to develop a relationship similar to the one between providers and consumers of electricity: the consumers are blissfully unaware of the details behind the provision of service - they simply get what they need when they need it. Hence, other names for the new business model are Utility Computing or Computing on Demand.

General Architecture of the Cloud

‘Cloud’ refers to both• The applications delivered as services over the

Internet (referred to as SaaS), e.g., Google search, Google calendar

• The hardware and systems software in the datacenters that provide those services (referred to as IaaS and PaaS), e.g., Google infrastructure and Google Big Table.

Service providers enjoy greatly simplified software installation and maintenance and centralized control over versioning; end users can access the service “anytime, anywhere”, share data and collaborate more easily, and keep their data stored safely in the infrastructure without provisioning a datacenter

Business Benefits of the Cloud Computing • The illusion of infinite computing resources available on demand,

thereby eliminating the need for Cloud Computing users to plan far ahead for provisioning• The elimination of an up-front commitment by Cloud users, thereby

allowing companies to start small and increase hardware resources only when there is an increase in their needs• The ability to pay for use of computing resources on a short-term basis

as needed (e.g., processors by the hour and storage by the day) and release them as needed, thereby rewarding conservation by letting machines and storage go when they are no longer useful

Technological Foundation of the Cloud Computing

• Virtualization of resources • Wikipedia: “… it is a paradigm shift whereby details are abstracted from the users

who no longer need knowledge of, expertise in, or control over the technology infrastructure "in the cloud" that supports them”.

• Web-scale distributed computation• Highly distributed computational models that can work on commodity hardware,

and software that supports them. The most commonly used distributed computational model is Google’s Map/Reduce

• New data storage solutions that leverage the distributed computing paradigm: Google Bigtable, Amazon SimpleDB, open source HBase (based on Google BigTable), and some others

• Open-source software also plays a role as it reduces cost barriers to the needed software components

Today’s Presentations•H. Martinez and S. Lin – The role of virtualization on the Cloud

•K. Mothana and C. Ozoria – The Google’s Big Table