You’ve probably heard of the different types of cloud computing services that end in “aaS” before: Infrastructure-as-a-Service, Platform-as-a-Service, and Software-as-a-Service. There are, however, key differences between these cloud computing service models in the value they provide and which customers they serve.
Definitions of IaaS, PaaS, and SaaS
Definition of IaaS
IaaS is the core offering of cloud service providers. Without them, all companies would have to own and maintain physical infrastructure (think servers). Instead, cloud service providers like Amazon Web Services (AWS), own data centers that house physical resources in on-premises infrastructure. The physical compute, memory, and networking resources (CPU, RAM, and bandwidth) are contained in virtual machines through virtualization; for example, Amazon EC2 instances are composed of these resources. IaaS services provide access to these resources for anyone with an internet connection willing to pay for them, from indie developers to large enterprises; essentially, they're renting out parts of a server they own. Customers then access the resources that have gone through virtualization through an application programming interface or dashboard on their web browser provided by the IaaS providers.
Examples of IaaS
There are a wide range of IaaS vendors, such as Amazon Web Services, Google Cloud Infrastructure, Microsoft Azure, IBM Cloud, Oracle Cloud Infrastructure, and Digital Ocean.
Definition of PaaS
A PaaS offers a layer of abstraction on top of the underlying IaaS. The original PaaS that revolutionized the space was Heroku; it provided engineers with a convenient way to test, deploy, and manage their applications without having to manage the underlying infrastructure. While IaaS provides cloud services, managing that infrastructure requires a level of technical expertise. While large companies can afford to build out a team of DevOps engineers whose sole job is to is the management of infrastructure, such a solution isn't feasible for hobby developers or even smaller organizations with limited financial resources. And so, PaaS solutions come into play. This cloud computing model allows for accessibility through an application programming interface or dashboard on a web browser just like IaaS tools.
A wide range of PaaS solutions
There are a wide range of PaaS tools that have varying pricing models, different levels of security, reliability, scalability, and flexibility (especially when it comes to the level of configuration and customization they offer). Some are multi-cloud, and some only host in the public, private, or hybrid cloud.
Examples of PaaS
Database-as-a-Service is another type of PaaS model that offers managed databases.
If you’re looking to learn more about PaaS specifically, please feel free to read this article.
Definition of SaaS
Although SaaS is a cloud service model, it doesn’t serve the same customer demographic as IaaS solutions and PaaS providers; that is, IaaS and PaaS solutions are used to build software applications, but SaaS tools can be utilized by people with far less technical knowledge or proficiency as they are simply applications available through the cloud and have simple accessibility through a web browser. SaaS applications have a much wider range of end users.
Examples of SaaS
Some examples of SaaS products are DocuSign eSignature, Figma, DropBox Paper, Mixpanel, and Google Workspace.
IaaS vs PaaS vs SaaS: Benefits of Each Cloud Computing Service
These three cloud service models have key differences in benefits, explaining their exponential proliferation in recent years.
IaaS allows corporations to not have to own and maintain their own data centers that contain on premises infrastructure, or even worry about allocating server space. Rather, they pay for cloud resources on-demand.
IaaS also allows for considerable flexibility, as users of an IaaS model have complete control over their infrastructure and how they want to configure it.
PaaS allows companies and individuals to forgo the management and maintenance of the underlying cloud infrastructure (work that falls under the umbrella of DevOps), meaning they really only have to be concerned with application development. PaaS allows engineering teams to perform testing and deployments of their applications without worrying about infrastructure.
For more information regarding the advantages of PaaS, please read on here.
SaaS apps allow individuals and companies to utilize pre-built software in the form of apps or APIs that serve specific use cases. Mixpanel, for example, is a SaaS platform that allows users to create dashboards for product analytics. Google Workspace lets users send emails, type up documents, and manage their calenders.
IaaS vs PaaS vs SaaS: Challenges of Each Cloud Computing Service
There are also key differences in terms of the challenges associated with each of these cloud service models, as well.
The management of infrastructure through the API or dashboard provided by IaaS services is not simple, and requires specialized technical knowledge. Another primary concern with IaaS relates to vendor lock-in, as it may be difficult to move from one IaaS to another through a cloud migration. The cost of an IaaS can also become exorbitant, but is generally more cost efficient to use the cloud over managing physical infrastructure.
The disadvantage of using a PaaS is that it can restrict engineering teams’ control over their infrastructure. Too much convenience can result in a lack of flexibility. Furthermore, these platforms can become prohibitively expensive as costs increase exponentially based on resource usage.
SaaS applications’ end users are much different from those of IaaS or PaaS, and one SaaS provider can look much different from one another. So, SaaS solutions don’t really factor into the choice when it comes to building applications.
IaaS vs PaaS vs SaaS: who’s the winner?
There is no best option out of these three cloud computing services as they all serve very different use cases for disparate business needs. However, a comparison can be made between the use case of an IaaS and a PaaS.
IaaS vs PaaS
When it comes down to a comparison of similar use cases for software engineers, the real concern is whether to manage your own infrastructure through IaaS providers or to utilize PaaS tools. Generally, the pricing model of PaaS services is more cost and time efficient than the management of infrastructure by a small engineering team, but it is certainly possible to manage an IaaS directly.
Choice in cloud provider can be determined by a number of factors. For startups, each of the cloud providers generally offer credits which act as a great incentive to choose one over the other. Other than monetary considerations, each IaaS also has an ecosystem of offerings that are only compatible with their IaaS, and that can also factor into the decision. Furthermore, a company’s industry may necessitate the use of certain technologies; for companies that run artificial intelligence or machine learning related workloads, GPU is a necessary compute resource. Microsoft Azure, for example, has a partnership with NVIDIA to further GPU-acceleration on the cloud; this may be a consideration for these sorts of companies. Also, some IaaS tools may not have support for legacy systems while others do.
A lot of factors can go into choosing between one PaaS versus another. Cost can be a primary consideration for many companies, but for others, the security of their data may be a larger factor. A private PaaS, for example, offers greater security than a platform hosted in the public cloud; corporations that have data security concerns will generally want to use a VPC. Most PaaS options offer service level agreements, but they may differ in how stringent they are. If a company has a microservices based architecture, they may prioritize utilizing Kubernetes for the scalability benefits the container orchestrator; only some PaaS providers run on K8s under the hood. Some companies may just want extreme convenience in their deployment process, and therefore look for the PaaS with the best developer experience. Like choosing an IaaS, there are a lot of considerations that need to be made.
Porter may be the PaaS for you
Porter is a multi-cloud PaaS that runs in users’ own private cloud, providing superior security and reliability in comparison to many other public PaaS offerings. It runs on Kubernetes under the hood, allowing for greater scalability, and does not restrict users from configuring their infrastructure directly, resulting in true flexibility. Furthermore, Porter’s pricing model is designed in a way that the velocity of spend decreases as users’ resource usage increases; there are volume discounts available for users with high compute and memory usage.