Cloud Computing: Today and Tomorrow.
Won Kyum Kim · The Journal of Object Technology · 2009
During the past few years, cloud computing has become a key IT buzzword.Although the definition of cloud computing is still "cloudy", the trade press and bloggers label many vendors as cloud computing vendors, and report on their services and issues.Cloud computing is in its infancy in terms of market adoption.However, it is a key IT megatrend that will take root.This article reviews its definition and status, adoption issues, and provides a glimpse of its future and discusses technical issues that are expected to be addressed. STATUSPerhaps the simplest working definition of cloud computing is "being able to access files, data, programs and 3 rd party services from a Web browser via the Internet that are hosted by a 3 rd party provider"[Hodson08] and "paying only for the computing resources and services used".Often cloud computing is used synonymously, inaccurately in my view, with such terms as utility computing (or on-demand computing), software as a service (SaaS), and grid computing.Of these, as I will show below, utility computing and SaaS are merely two of several forms of service cloud computing can provide.Grid computing is simply one type of underlying technologies for implementing cloud computing.The term "cloud" in cloud computing is used synomously with "data center".Today the computing field is able to envision transitioning into the cloud computing era because of the breath-taking advances in computing and information technologies during the past three decades.The advances include the buildup of the Internet backbone, the widespread adoption of broadband access to the Internet, the powerful network of servers and storage in data centers, the advances in high performance and scalable software infrastructure for the data centers and the Web, etc.The architecture of a cloud includes several key modules [Wikipedia]: user interaction interface, system resource management module with a services catalog, and resource provisioning module.The system resource management module manages a massive network of servers running in parallel.Often it also uses virtualization techniques to dynamically allocate and deallocate computing resources.