IaaS vs PaaS vs SaaS – cloud service models compared

IaaS vs PaaS vs Saas – various cloud service models compared

Do you know the difference between your cloud service models? Can you tell your IaaS from your PaaS and SaaS? The list of cloud-based services is long, and continually growing. But, if you want to know which solution is right for your business. First you need to understand the various configurations. Each different solution is like a remote Lego model. And each brick is like a piece of the infrastructure. Or an application that your business needs.

So, here’s an introduction and useful comparison to some of the -aaS services out there. Let us help you understand. So in the future you don’t get your SaaS confused with your PaaS.

IaaS, PaaS, and SaaS – how do they differ?

IaaS, PaaS, and SaaS – how do they differ? - plesk

Trying to understand the concepts behind cloud services can sometimes feel like you’re grasping at…well clouds really. It’s tricky to think of IaaS vs PaaS, PaaS vs SaaS, or IaaS vs SaaS if you have no idea what they mean.

Infrastructure-as-a-Service, Platform-as-a-Service, and Software-as-a-Service may have you scratching your head. But they subtly describe the different tasks and responsibilities service providers offer.

1. IaaS (Infrastructure-as-a-Service) offers environments that are scalable, controllable and automated.

2. PaaS (Platform-as-a-Service) provides a framework that lets you create and release applications quickly. It also automates and manages the provision of infrastructure.

3. SaaS (Software-as-a-Service) allows programs to run remotely and is accessible through the Internet. So you don’t need to run a program from a certain device.

Defining cloud computing services – IaaS, PaaS, SaaS

Defining cloud computing services - IaaS, PaaS, SaaS - plesk

So, the concept of as-a-Service seems clear. Whatever the first letter stands for, that’s what’s available to anyone, anywhere with an Internet connection.

The advantage of Cloud services is that you can increase or decrease the amount of remote resources you need. You pay for what you use – paying more when you need it, and less when you don’t. Moving data and business processes to the cloud gives unmatched flexibility. Now businesses no longer have to deal with the logistical and financial headaches of old-style IT.

IaaS stands for “Infrastructure-as-a-Service”

IaaS stands for “Infrastructure-as-a-Service”

Investing in servers and hardware probably aren’t top of your Christmas list. You have to manage them. Then they take up space. Plus they depreciate. Investing in IaaS is probably the gift you really want. IaaS allows you to create and manage virtual, pre-configured machines. You can also deploy computing power in less time – without the complexity.

Amazon Web Services’ IaaS is called the Elastic Compute Cloud, or EC2. IaaS packages like this look after storage and networking, as well as servers and virtualization components. All you need to do is simply install it. Then maintain the operating system, databases, security components, and applications.

PaaS stands for “Platform-as-a-Service” plesk

PaaS stands for “Platform-as-a-Service”

PaaS lets you write and test code. All without worrying about managing the system you’re working on. Developers particularly like PaaS for this reason. It just lets them get on with developing. PaaS products also include APIs and other tools for developers to add features. Tools such as traffic splitting, monitoring, and version control systems.

Microsoft Azure and Google Cloud Platform are popular PaaS examples. You’ll find out more about them in the in-depth examples section.

SaaS means “Software-as-a-Service” plesk

SaaS means “Software-as-a-Service”

Gmail, Dropbox, Salesforce, and Netflix are all well-known examples of SaaS applications. All of the storage and computational heavy lifting happens in the cloud. You then access the fruits of these labors over the Internet via a browser-based interface.

SaaS apps allow you to make use of tools. And you don’t have to worry about fixing or maintaining them. Moreover, data is backed up and happens automatically. It’s all off-site, so you don’t have to worry about how it all works. What you do have to worry about is that it can still break. This is crucial as a SaaS provider is the custodian of all your most important stuff. You need to trust they’ve got robust security. And that their service won’t go down when you need it most.

Cloud service models for IaaS, PaaS and SaaS

Cloud service models for IaaS, PaaS and SaaS- plesk

The cloud industry is continually growing. Research company Forrester thinks the cloud market will grow from $146 billion in 2017 to $236 billion in 2020. Their report suggests providers will increase the number of available services and computing models. They’ve seen an upsurge in new cloud adopters, all benefiting from the cloud’s efficiency. Forrester also thinks regional and industry-specific services will be offered – coming from new and more diverse cloud providers.

With Office 365, Azure, and virtual machines, Microsoft covers the cloud-model trifecta.

Amazon Web Services was on the crest of the first cloud computing wave when it started in 2006, according to CIO. This pegs the company’s current revenue at around $11 billion a year. Microsoft Azure currently sits in second place as a cloud provider. Furthermore, it recently reported a 100% increase in quarterly growth over the previous year. Microsoft offers 600+ services in just its Azure suite alone. It also covers all three cloud computing models.

PaaS vs. IaaS with Microsoft Azure plesk

PaaS vs. IaaS with Microsoft Azure

Azure offers a slew of fast and convenient virtual servers. Each server is available in the blink of an eye. Fitted with the language, workload, and operating system of the superuser. Azure supports pre-configured server images to make deployment simple. But users can also dive in and create their own bespoke configurations.

PaaS-wise, Azure Cloud Services provides developers with plenty of language and framework options. And thankfully none of the headaches of infrastructure management. Azure integrates with the Azure SDK and Visual Studio to further ease the development journey.

Azure Emulator mimics cloud functionality on a user’s local machine. So cloud apps can be tested off-line before deployment. Once deployed, Cloud Services takes care of automatic operating system and application patching. Along with integrated health, monitoring, and load-balancing tools.

Microsoft Office SaaS

Microsoft Office SaaS

Some Azure components might drift into SaaS functionality. But Office 365 is a straightforward example of SaaS. Office 365 offers online versions of old favorites. With apps like Word, Excel, PowerPoint, OneDrive, and Outlook. Subscription plans vary for home, business, and enterprise users. The apps are also available for web browsers and mobile.

Understanding the cloud computing stack (IaaS, PaaS, SaaS)

New York-based cloud provider Apprenda compares cloud computing platforms to the power grid. Lightbulb users don’t need to know how power is generated. They just “see the light.” Similarly, cloud users don’t need to know how the cloud works.

The WebSpecia blog explains IaaS, PaaS, and SaaS using a transportation analogy. Thus IaaS is like a lease car arrangement, while PaaS is like getting a cab. Meanwhile, SaaS is more like using a bus or the subway.

Think of IaaS, PaaS, and SaaS cloud computing models in whatever way makes sense to you. Hopefully this guide to cloud service models has helped un-muddy some of your thoughts. And given you a clearer idea about on-demand services. Once you’re familiar with the three main configurations, you can begin your journey through the myriad of other options.

Which do you think is best for your business? Let us know in the comments below.

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What Are Cloud Service Providers?

Cloud Service Providers

Cloud service providers ( CSP ) is the name given to any of those companies that offer some component of cloud computing as a service. You know the ones? They all have initials that end in “aaS”. So, you’ll see infrastructure as a service (IaaS), software as a service (SaaS) or platform as a service (PaaS). Let’s take a look at what each one of these common acronyms means.

IaaS Providers

IaaS means that the cloud service provider owns and maintains all the hardware and software that the customer would normally have to buy and look after in their own data center. This means that the building that contains all the many boxes with their CPUs, memory, cooling, power supplies and all the rest of it live elsewhere, and the customer only needs to connect to use it.

The IaaS cloud service provider will also monitor everything, protecting it around the clock from cyber attackers, and providing other services like load balancing.

SaaS providers

SaaS gives the customer access to a number of business technologies like productivity solutions, customer relationship management (CRM) software and human resources management (HRM) software. The SaaS provider looks after it all, so again, the customer just dials in to use it.

Lots of software suppliers have made the move to cloud-based services now, so there’s often no need for customers to buy physical media from them.

PaaS providers

Platform as a service combines cloud infrastructure and services together, and it’s often used in software development. The difference compared to IaaS is that PaaS vendors will add  more of the application stack to the underlying infrastructure; things like operating systems and middleware.

Cloud providers can also be divided up according to whether they provide public, private or hybrid cloud services.

Common features and offerings

Cloud service providers typically allow users to purchase their offerings or subscribe on an ongoing basis.

Some cloud providers have tailored their products to the requirements of particular vertical markets. They’ve adapted their services in the cloud to meet the requirements of specific industries or they’ve customized them so that users can meet particular regulations. For example, a number of health-related cloud products are on the market and they allow healthcare providers to store, maintain and back up their users’ personal data.

Major cloud service providers

There are many cloud services providers out there, but it’s likely that you’ll only have heard of the really big ones: Amazon Web Services (AWS), Microsoft Azure and Google Cloud.

Amazon was first to become a major cloud provider in 2006 with Amazon Simple Storage Service (Amazon S3). Microsoft came along with its Azure platform and then Google with its Google Cloud Platform. The market has grown and now these three dominant companies jostle for the lead share in many different corners of it.

At the moment, they are all working on cloud-based services that make use of emerging technologies like machine learning, artificial intelligence (AI) and containerization. Major cloud providers beyond the top three include Apple, Citrix, IBM, Joyent, Rackspace and Salesforce.

How to choose a cloud service provider

Choosing a cloud service provider involves looking at a number of factors. Cost is the main one, and you will normally pay depending on what you use, but you should be aware that this isn’t the only type of payment model.

What it’s going to cost you is of course important, but you might also want to consider where the servers are actually located if they need to deal with sensitive information.


Reliability is crucial for the same reason that security is: your data is being kept somewhere else, so your ceding control of it to someone else. Reliability means knowing that you can access it all the time, and if you can’t, then that can spell big trouble for your business.

It’s worth noting that many cloud storage providers will promise 99.9% uptime in their service-level agreements (SLAs), and they will also spell out what kind of compensation you stand to receive if they can’t meet their promised level of service provision.

This sounds reassuring, but you do take care to read the small print in SLAs because some providers won’t count down time if it doesn’t exceed 10 minutes. If that doesn’t sound like much to you, then great. Perhaps your business can stand that kind of outage. But 600 seconds could be an eternity of dead time that costs companies in the financial sector (for example) a fortune.


Security is an equally important area, but without visiting their premises poking around, it’s often hard to know how secure a cloud service provider really is. One thing you can look for here is the blessing of recognized bodies which set minimum standards.

Organizations like the Cloud Security Alliance (CSA) will certify cloud providers that meet their requirements, so check whether your cloud provider is certified by them.

The CSA’s Trusted Cloud Initiative program is another scheme to look out for. It was set up to aid cloud service providers in developing secure and interoperable identity, access and compliance management configurations and practices that are recommended by the industry.