CLOUD COMPUTING SERVICE

                    CLOUD COMPUTING

CLOUND COMPUTING:- 

 In simple word cloud computing is enable on-demand service like compute , storage , networking , etc. Which can be accessed through the internet and the user is not required to manage these resources.

Features - Pay as you go - Scalable - flexible - Secure & Disaster Recoveries 

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 Cloud computing is providing computing resources (IaaS, PaaS, SaaS) as a service over the N/W. Cloud computing is using computing resources managed by provider and "pay as per usage". The service provider will take care of infrastructure management and user needs to pay only for service used. 

Private Cloud:-

 Private cloud is one in which the services and infra are maintained on a private network. These cloud offer the greatest level of security and control , but they require the company to still purchase and maintain all the software and infra , which reduces the cost saving.

Public Cloud:- 

 Public cloud is extension of private cloud with additional cost- benefit due to service provider orients low cost cloud storage to enterprise, public cloud like MS windows Azure passed the benefit of shared infrastructure and automation in term of low-cost.

Cloud Service Models:-

IAAS:-

 The base layer. Provides the computing infrastructure physical or virtual machine and other resources like virtual machine, storage, firewalls, load balancers, IP addresses, virtual local area N/W etc. Ex:- AWS EC2, MS Windows Azure. IaaS is more popular among users into research and high computing area. IAAS allows customers to increase their computational and storage resources on the fly without investing in new hardware known as virtualization. Virtualization enables running multiple operating system instances called virtual machine Google Compute Engine ( one can develop programs to be on high performing google infra.

PAAS:-

 A layer on top of IAAS.  Provides you computing platforms which typically include operating system, programming language execution environment, database, web server etc. Ex:- AWS Elastic Beanstalk, Force.com, Google App  Engine. Runtimes (like java), DB, Web Servers. PAAS is more popular among developers as they can put all their on developing their on developing their apps and leaves the rest of management and execution to the service provider. Many service providers also offer the flexibility increase/decrease  the CPU power depending upon the traffic loads giving developers cost effective and easy & effortless management. Google App Engine ( one can apps and let them execute on top of google app engine which take care of the execution. 

SAAS:- 

 A layer on top on PAAS. PAAS is a model where an application is hosted on a remote data center and provided as a service to customers across the internet. In this model the provider takes care of all software development , maintenance and upgrade. The provider also provides supports and maintains the data center. Ex:- Google apps, MS Office 365, Application like email ( Gmail, yahoo), Social N/W sites (FB etc), Gmail , Google+ etc ( one can use email service and extend emails/google+ based application to form newer applications)