Describe the services provided under cloud computing.


Cloud computing service models are divided into three categories: Infrastructure as a Service (IaaS), Platform as a Service (PaaS), and Software as a Service (SaaS) (SaaS). There are evident distinctions between the three in terms of what they can provide a business in terms of storage and resource sharing, but they may also interact with one another to build a single comprehensive cloud computing platform.

1. IaaS (Infrastructure as Service):

 This is the most prevalent cloud computing service architecture since it provides the underlying infrastructure of virtual servers, networks, operating systems, and data storage devices. It provides the flexibility, stability, and scalability that many organizations desire from the cloud while eliminating the need for hardware in the office. This makes it excellent for small and medium-sized businesses seeking a cost-effective IT solution to support business growth. IaaS is a completely outsourced pay-for-use service that is accessible as a public, private, or hybrid infrastructure.

2. PaaS (Platform-as-a-Service): 

The infrastructure and software foundation is deployed here by cloud computing providers, but enterprises can design and run their applications. PaaS allows for the rapid and easy creation of web apps, and the service is versatile and resilient enough to sustain them. PaaS solutions are scalable and suited for corporate scenarios with several developers working on a single project. It is also useful in cases when an existing data source (such as a CRM program) must be used.

3. SaaS (Software as a Service): 

This cloud computing approach entails the distribution of software through the internet to numerous enterprises that pay via subscription or pay-per-use. It is a useful tool for CRM and apps that require a lot of online or mobile access, such as mobile sales management software. SaaS is handled from a single place, removing the need for enterprises to worry about maintaining it themselves, and thus is suitable for short-term initiatives. 


i. Infrastructure as a service(Iaas): This service provides IT infrastructures such as servers, networking, processing, storage, virtual machine, and other resources. We can access these resources using a pay-as-per-use model. It contains SSN service(Server, Storage, and Network). Iaas is used by system Administrators.

ii. Platform as a service(Paas): This service provides a runtime environment and Encapsulation. It allows programmers to create, test, run and deploy web applications. We can manage data and application resources. It is used by developers.

iii. Software as a service(Saas): Using  Saas, we can access software over the internet without the need of any platform. In this service, we don’t need the work of H/W and O/S, we have to access the services on a web browser or application.


Software as a Service(SaaS)

  • Software-as-a-Service (SaaS) is a way of delivering services and applications over the Internet. Instead of installing and maintaining software, we simply access it via the Internet, freeing ourselves from complex software and hardware management. It removes the need to install and run applications on our own computers or in the data centers eliminating the expenses of hardware as well as software maintenance.
  • SaaS provides a complete software solution that you purchase on a pay-as-you-go basis from a cloud service provider. Most SaaS applications can be run directly from a web browser without any downloads or installations required. SaaS applications are sometimes called Web-based software, on-demand software, or hosted software.

Advantages of SaaS

1. Cost-Effective: Pay only for what you use.

2. Reduced time: Users can run most SaaS apps directly from their web browser without needing to download and install any software. This reduces the time spent in installation and configuration and can reduce the issues that can get in the way of software deployment.

3. Accessibility: We can Access app data from anywhere.

4. Automatic updates: Rather than purchasing new software, customers rely on a SaaS provider to automatically perform the updates.

5. Scalability: It allows the users to access the services and features on-demand.

The various companies providing Software as a service are Cloud9 Analytics,, Cloud Switch, Microsoft Office 365, Big Commerce, Eloqua, dropBox, and Cloud Tran.

Platform as a Service

  • PaaS is a category of cloud computing that provides a platform and environment to allow developers to build applications and services over the internet. PaaS services are hosted in the cloud and accessed by users simply via their web browser.
  • A PaaS provider hosts the hardware and software on its own infrastructure. As a result, PaaS frees users from having to install in-house hardware and software to develop or run a new application. Thus, the development and deployment of the application take place independent of the hardware.
  • The consumer does not manage or control the underlying cloud infrastructure including network, servers, operating systems, or storage, but has control over the deployed applications and possibly configuration settings for the application-hosting environment. To make it simple, take the example of an annual day function, you will have two options either to create a venue or to rent a venue but the function is the same.

Advantages of PaaS:

1. Simple and convenient for users: It provides much of the infrastructure and other IT services, which users can access anywhere via a web browser.

2. Cost-Effective: It charges for the services provided on a per-use basis thus eliminating the expenses one may have for on-premises hardware and software.

3. Efficiently managing the lifecycle: It is designed to support the complete web application lifecycle: building, testing, deploying, managing, and updating.

4. Efficiency: It allows for higher-level programming with reduced complexity thus, the overall development of the application can be more effective.

The various companies providing Platform as a service are Amazon Web services Elastic Beanstalk, Salesforce, Windows Azure, Google App Engine, cloud Bess and IBM smart cloud.

Infrastructure as a Service

  • Infrastructure as a service (IaaS) is a service model that delivers computer infrastructure on an outsourced basis to support various operations. Typically IaaS is a service where infrastructure is provided as outsourcing to enterprises such as networking equipment, devices, database, and web servers.
  • It is also known as Hardware as a Service (HaaS). IaaS customers pay on a per-user basis, typically by the hour, week, or month. Some providers also charge customers based on the amount of virtual machine space they use.
  • It simply provides the underlying operating systems, security, networking, and servers for developing such applications, and services, and deploying development tools, databases, etc.

Advantages of IaaS:

1. Cost-Effective: Eliminates capital expense and reduces ongoing cost and IaaS customers pay on a per-user basis, typically by the hour, week, or month.

2. Website hosting: Running websites using IaaS can be less expensive than traditional web hosting.

3. Security: The IaaS Cloud Provider may provide better security than your existing software.

4. Maintenance: There is no need to manage the underlying data center or the introduction of new releases of the development or underlying software. This is all handled by the IaaS Cloud Provider.

The various companies providing Infrastructure as a service are Amazon web services, Bluestack, IBM, Openstack, Rackspace, and Vmware.


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