(18)What is cloud computing? List down characteristics of cloud computing.

Answer:
  • Cloud computing is the practice of using remote servers hosted on the Internet to store, manage, and process data, rather than a local server or a personal computer.
  • Cloud computing, simply means the use of computing resources as a service through networks, typically the Internet. 
  • The Internet is commonly visualized as clouds; hence the term “cloud computing” for computation done through the Internet. 
  • With Cloud Computing, users can access database resources via the Internet from anywhere, for as long as they need, without worrying about any maintenance or management of actual resources. 
  • Cloud computing relies on sharing of resources to achieve coherence and economies of scale, similar to a public utility.


Characteristics of Cloud Computing:

(1)On-demand Service:
  • A consumer can unilaterally provision computing capabilities, such as server time and network storage, as needed automatically without requiring human interaction with each service provider.

(2)Broad network access:
  • Capabilities are available over the network and accessed through standard mechanisms that promote use by heterogeneous client platforms (e.g. mobile phones, tablets, laptops, and workstations).


(3)Multi Tenancy:
  • The cloud service provider’s computing resources are pooled to serve multiple consumers using a multitenant model, with different physical and virtual resources dynamically assigned and reassigned according to consumer demand.

(4)Resiliency:
  • In case of disruption, whole IT infrastructure or work is migrated to a different physical resource in the cloud with or without user awareness and intervention.


(5)Elasticity and Scalability:
  • Capabilities can be elastically provisioned and released, in some cases automatically, to scale rapidly outward and inward commensurate with demand.
  • To the consumer, the capabilities available for provisioning often appear to be unlimited and can be appropriated in any quantity at any time.

(6)Pay per Usage:
  • Resource usage can be monitored, controlled, and reported, providing transparency for both the provider and consumer of the utilized service.
  • Payment for using cloud service made based on usage of cloud services.


(7)Workload Movement:
  • Cloud systems automatically control and optimize resource use by leveraging a measuring/monitoring capability at some level of abstraction appropriate to the type of service (e.g., storage, processing, bandwidth, and active user accounts).
  • Also, Cloud Computing providers can migrate work load across servers both inside datacenter and between datacenters in different geographical location.