Cloud Technology - A Future Technology

20^th century- the age of Information technology changed the whole way of life from living to eating, travelling to communicating and working to enjoying. This new technology also introduced additional challenges like security, confidentiality, privacy and data management issues. As per (EMC, 2014) size of digital data is increasing with the rate more than 50%. This implies that the total size of digital data will be doubled every two years and this rate is increasing constantly. As per press release of Gartner - (Gartner, 2014) , one third of personal data will be on web by 2016. Current technology would not be able to cope up with this and it would be a great challenge to manage this big chunk of data. Security and privacy of data would be another major concern.

To address these challenges, there is introduction of new technology – Advanced Computer Technologies. 21^st century will be the age of Advanced Computer Technologies which is also very well-known by abbreviation ACT.

ACT is categorized into four major components.

• Cloud Computing India
• Cluster Computing
• Distributed Computing
• Grid Computing

i)       Cloud Computing

Cloud computing has been seen as the next revolution of IT and the most famous ACT category. It will radically change the way of working. Cloud computing has a great influence on all kinds of enterprises.

Cloud is a large pool of easily usable and accessible virtualized resources which could be hardware, development platforms and/or services. According to that one can divide cloud into four types: NaaS cloud (Network as a Service), SaaS (Software as a Service) cloud, PaaS (Platform as a Service) cloud and IaaS (Infrastructure as a Service) cloud. All of these can be reconfigured to adjust to a variable load dynamically, allowing also for optimum resource utilization. And, these resources are typically exploited by a pay-per-use model in which guarantees are offered by the Infrastructure Provider by means of customized Service-Level Agreements.

In developed country like USA, Canada, etc. many small scaled companies has started using Cloud technology for various departments. They received following benefits because of implementation of cloud technology.

1. Very high cost reduction
2. Less monitoring and maintenance of IT infrastructure
3. Higher scalability and flexibility

ii)    Cluster Computing

A computer cluster consists of a set of loosely connected or tightly connected computers that work together so that in many respects they can be viewed as a single system. The components of a cluster are usually connected to each other through fast local area networks ("LAN"), with each node (computer used as a server) running its own instance of an operating system. Computer clusters emerged as a result of convergence of a number of computing trends including the availability of low cost microprocessors, high speed networks, and software for high performance distributed computing.

iii)  Distributed Computing

(wikipedia, 2014) Defines distributed computing as a field of computer science that studies distributed systems. A distributed system is a software system in which components located on networked computers communicate and coordinate their actions by passing messages. The components interact with each other in order to achieve a common goal. Three significant characteristics of distributed systems are: concurrency of components, lack of a global clock, and independent failure of components. Examples of distributed systems vary from SOA-based systems to massively multiplayer online games to peer-to-peer applications. A computer program that runs in a distributed system is called a distributed program, and distributed programming is the process of writing such programs. An important goal and challenge of distributed systems is location transparency.

iv)  Grid Computing

As per (Gridcafe, 2014) Grid computing is the collection of computer resources from multiple locations to reach a common goal. The grid can be thought of as a distributed system with non-interactive workloads that involve a large number of files. What distinguishes grid computing from conventional high performance computing systems such as cluster computing is that grids tend to be more loosely coupled, heterogeneous, and geographically dispersed. Although a single grid can be dedicated to a particular application, commonly a grid is used for a variety of purposes. Grids are often constructed with general-purpose grid middleware software libraries.

Grid size varies a considerable amount. Grids are a form of distributed computing whereby a “super virtual computer” is composed of many networked loosely coupled computers acting together to perform large tasks. For certain applications, “distributed” or “grid” computing, can be seen as a special type of parallel computing that relies on complete computers (with onboard CPUs, storage, power supplies, network interfaces, etc.) connected to a network (private, public or the Internet) by a conventional network interface, such as Ethernet. This is in contrast to the traditional notion of a supercomputer, which has many processors connected by a local high-speed computer bus.