3 Types of Cloud Computing Service Models The MSP HUB IBM Blog

IaaS, PaaS, & SaaS: 3 cloud-based As-a-Service models


As a service models are provided by vendors giving users access to computing resources such as servers, storage and networking via cloud computing.

What is cloud computing?

Put simply, it’s a model for enabling convenient, on-demand network access to a shared pool of specialised computing resources.

Computing resources that might otherwise lie beyond a clients’ means, due to either cost or complexity of operation.

The efficiencies of sharing infrastructure has even led to a beneficial lowering of costs for these services.


Choosing the right cloud model

The main categories of cloud computing services fall into three areas or models:

Infrastructure as a Service (IaaS)

Platform as a Service (PaaS)

Software as a Service (SaaS)

It is the unique business drivers and application needs of each company that determines which model best suits them.

The whole point of cloud-server accessed services is that they allow clients to take advantage of systems tailored to their own needs.


Which As a Service model is right for you?

You need to take a hard and honest look at the expertise and size of your team

Take into account, too, the existing architecture your present systems are based upon.

You also need to consider the level of agility and flexibility you’re expecting from the new capabilities being accessed.

Whether you’re planning on moving to a private or public cloud, you’ll need to carry out a workload assessment, bearing in mind that each application and process required is an extra workload to consider.

Cost analysis, naturally, is key.

How much would new platform or infrastructure components cost you?

What would the cost of transition be? (High if this is a legacy rather than an actively-developed application.)

Of ongoing maintenance?

For instance, moving to a managed platform could completely eliminate those maintenance costs.

Along, too, with the costs of managing application upgrades.

So, the most relevant question is – just how much do you want to save?


The cloud technology solutions at a glance

Cloud computing services are continuing to evolve, with categories including Containers as a Service (CaaS) and Functions as a Service (FaaS) on the rise.

However, for the moment IaaS, PaaS, and SaaS: are the main models to consider.


Infrastructure as a Service Key Features

  • Instead of purchasing hardware outright, users pay for IaaS on demand.
  • Infrastructure is scalable depending on processing and storage needs.
  • Saves enterprises the costs of buying and maintaining their own hardware.
  • Because data is on the cloud, there can be no single point of failure.
  • Enables the virtualization of administrative tasks, freeing up time for other work.


Platform as a Service Key Features

  • PaaS provides a platform with tools to test, develop and host applications in the same environment.
  • Enables organizations to focus on development without having to worry about underlying infrastructure.
  • Providers manage security, operating systems, server software and backups.
  • Facilitates collaborative work even if teams work remotely.


Software as a Service Key Features

  • SaaS vendors provide users with software and applications via a subscription model.
  • Users do not have to manage, install or upgrade software; SaaS providers manage this.
  • Data is secure in the cloud; equipment failure does not result in loss of data.
  • Use of resources can be scaled depending on service needs.
  • Applications are accessible from almost any internet-connected device, from virtually anywhere in the world.


Infrastructure as a Service in Detail

A client accesses block storage, networking, computing capacities and various other virtualised infrastructure components, hosted and managed by a cloud provider.

The lowest level of cloud provider services, Infrastructure as a Service provides the building blocks for clients to activate virtual machines and other components, granting them a high degree of control over the specific operating system, middleware, databases.

The client choses the architecture, estimates resource requirements, and provisions, configures, and scales these components where necessary.

They don’t have to worry about the hardware and underlying network as this remains the responsibility of the provider.

This offloads a great deal of a company’s traditional IT costs, such as the regular maintenance of all these assets and networks.

It also negates the need for up-front capitalisation costs of on-premise data centres.

What’s more, when demand for a clients’ services briefly drop off, perhaps suffering a seasonal low, operating costs can be minimised, for scaling vertically or horizontally across the globe can be done in a few clicks.


Is Infrastructure as a Service right for you?

IaaS provides an infrastructure for your business initiatives that can be expanded or terminated when and as needed.

If your business presently lacks an owned data centre, and you don’t wish to put forward the capital expenditure to create one, IaaS will supply you with all the compute power you need to run variable workloads.

You’ll only pay for the services you use. So you can start small, with a single application on a small server.

You can also scale up or down at your own pace, such as when demand falls in seasonal or cyclical business models.


Platform as a Service in Detail

A level up from IaaS, Platform as a Service provides client companies with a cloud environment on which they can more easily develop, deploy and manage their own applications and software, enabled by a suite of prebuilt tools.

The process of configuring, provisioning, and scaling IaaS components is effectively automated, as the provider supplies and handles the provisioning and regular updating of the underlying infrastructure and servers.

This includes managing the operating system, middleware, runtimes, and databases.

Clients create their online applications in ready-made platforms supported by the provider, leveraging programming languages, libraries, services, and tools.

Developing their own code for the apps, the clients store it in the PaaS provider’s datacentre, then publish the apps.

These clients retain control over the deployed applications, as well as any necessary configuration settings for the application-hosting environment.


Is Platform as a Service right for you?

Do you want to focus on creating and deploying applications quickly?

Or, maybe, you have a new project in mind that’s not compatible with your existing infrastructure?

PaaS reduces both time-to-market and operational costs, as pricing is typically consumption-based.

It the best way to test and prototype new services or applications as they’re released more quickly than usual, allowing swift user feedback.

You have less control and flexibility, but don’t have to worry about managing the hardware, planning for capacity, or security.


Software as a Service in Detail

Software as a Service offers clients cloud-hosted, ready-to-use software and applications.

Having subscribed to use the software, users access it on their devices through either a thin client interface, such as a web browser (e.g., web-based email), or the providers’ own Application Programme Interfaces (APIs).

Here they can take advantage of facilities including monitoring, content, finance models, collaboration, and various means of communication.

For instance, the applications being accessed allow the users to store and analyse data, as well as collaborate on projects remotely.

As the applications reside on the providers’ remote cloud network, the client doesn’t need to build or install applications on their local devices.

Moreover, apart from limited user-specific application configuration settings, the client doesn’t need to be involved in any management or control of the underlying cloud infrastructure.

Network, servers, operating systems, maintenance, storage, and even individual application capabilities, all remain the responsibility of the provider.

The same goes for updates and security fixes.


Is Software as a Service right for you?

Naturally, many companies want to benefit from application usage without the pain of constantly maintaining and updating the infrastructure and its complex components.

The SaaS model offers flexibility and elasticity

The software is installed via a web-based portal, rather than being purchased as a package from a store. Costs are in the form of paid licenses or user subscriptions and are therefore quite straightforward.

There’s also very little burden imposed on your in-house IT staff.


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