SaaS vs PaaS vs IaaS: What’s The Difference and How To Choose

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While the cloud is an extremely hot topic from small businesses all the way to global enterprises, it is still a pretty broad concept that covers a lot of online territory. As you begin to consider switching your business to the cloud, whether it be for application or infrastructure deployment, it is more important than ever to understand the differences and advantages of the various cloud services.

There are usually three models of cloud service to compare: Software as a Service (SaaS), Platform as a Service (PaaS), and Infrastructure as a Service (IaaS). Each of these has its own benefits as well variances and it is necessary to understand the differences among SaaS, PaaS, and IaaS to know how to best choose one for your organization.

SaaS: Software as a Service

Software as a Service, also known as cloud application services, represent the most commonly utilized option for businesses in the cloud market. SaaS utilizes the internet to deliver applications to its users, which are managed by a third-party vendor. A majority of SaaS applications are run directly through the web browser, and do not require any downloads or installations on the client side.

SaaS Delivery

Due to its web delivery model, SaaS eliminates the need to download and install applications on each individual computer; a nightmare for IT staff. With SaaS, vendors manage all of the potential technical issues, such as data, middleware, servers, and storage, while businesses can simply streamline their maintenance and support.

SaaS Advantages

SaaS provides numerous advantages to employees and companies by greatly reducing the time and money spent on tedious tasks such as installing, managing, and upgrading software. This frees up a lot of time for technical staff to spend on more pressing matters and issues within the organization.

SaaS Characteristics

There are a few ways to help you determine when SaaS is being utilized:

  • Managed from a central location
  • Hosted on a remote server
  • Accessible over the internet
  • Users not responsible for hardware or software updates

When to Use SaaS

There are many different situations in which SaaS may be the most beneficial, including:

  • If you are a startup or small company that needs to launch ecommerce quickly and don’t have time for server issues or software
  • For short-term projects that require collaboration
  • If you use applications that aren’t in-demand very often, such as tax software
  • For applications that need both web and mobile access

Examples of SaaS

Google Apps, Dropbox, Salesforce, Cisco WebEx, Concur, GoToMeeting

PaaS: Platform as a Service

Cloud platform services, or Platform as a Service (PaaS), provide cloud components to certain software while being used mainly for applications. PaaS provides a framework for developers that they can build upon and use to create customized applications. All servers, storage, and networking can be managed by the enterprise or a third-party provider while the developers can maintain management of the applications.

PaaS Delivery

The delivery model of PaaS is similar to SaaS, except instead of delivering the software over the internet, PaaS provides a platform for software creation. This platform is delivered over the web, and gives developers the freedom to concentrate on building the software while still not having to worry about operating systems, software updates, storage, or infrastructure.

PaaS allows businesses to design and create applications that are built into the PaaS with special software components. These applications, or middleware, are scalable and highly available as they take on certain cloud characteristics.

PaaS Advantages

No matter what size of company you may be in, there are numerous advantages for using PaaS:

  • Makes the development and deployment of apps simple and cost-effective
  • Scalable
  • Highly available
  • Gives developers the ability to create customized apps without the headache of maintaining the software
  • Greatly reduces the amount of coding
  • Automates business policy
  • Allows easy migration to the hybrid model

PaaS Characteristics

PaaS has many characteristics that define it as a cloud service, including:

  • It is built on virtualization technology, meaning resources can easily be scaled up or down as your business changes
  • Provides a variety of services to assist with the development, testing, and deployment of apps
  • Numerous users can access the same development application
  • Web services and databases are integrated

When to Use PaaS

There are many situations that utilizing PaaS is beneficial or even necessary. If there are multiple developers working on the same development project, or if other vendors must be included as well, PaaS can provide great speed and flexibility to the entire process. PaaS is also beneficial if you wish to be able to create your own customized applications. This cloud service also can greatly reduce costs and it can simplify some challenges that come up if you are rapidly developing or deploying an app.

Examples of PaaS

AWS Elastic Beanstalk, Windows Azure, Heroku, Force.com, Google App Engine, Apache Stratos, OpenShift

IaaS: Infrastructure as a Service

Cloud infrastructure services, known as Infrastructure as a Service (IaaS), are made of highly scalable and automated compute resources. IaaS is fully self-service for accessing and monitoring things like compute, networking, storage, and other services, and it allows businesses to purchase resources on-demand and as-needed instead of having to buy hardware outright.

IaaS Delivery

IaaS delivers Cloud Computing infrastructure to organizations, including things such as servers, network, operating systems, and storage, through virtualization technology. These cloud servers are typically provided to the client through a dashboard or an API, and IaaS clients have complete control over the entire infrastructure. IaaS provides the same technologies and capabilities as a traditional data center without having to physically maintain or manage all of it. IaaS clients can still access their servers and storage directly, but it is all outsourced through a “virtual data center” in the cloud.

As opposed to SaaS or PaaS, IaaS clients are responsible for managing aspects such as applications, runtime, OSes, middleware, and data. However, providers of the IaaS manage the servers, hard drives, networking, virtualization, and storage. Some providers even offer more services outside of the virtualization layer, such as databases or message queuing.

IaaS Advantages

There are many benefits of choosing IaaS, such as that it:

  • Is the most flexible cloud computing model
  • Easily allows for automated deployment of storage, networking, servers, and processing power
  • Hardware can be purchased based on consumption
  • Gives clients complete control of their infrastructure
  • Resources can be purchased as-needed
  • Is highly scalable

IaaS Characteristics

Some characteristics to look for when considering IaaS are:

  • Resources are available as a service
  • The cost varies depending on consumption
  • Services are highly scalable
  • Typically includes multiple users on a single piece of hardware
  • Provides complete control of the infrastructure to organizations
  • Dynamic and flexible

When to Use IaaS

Just as with SaaS and PaaS, there are specific situations when it is the most advantageous to use IaaS. If you are a startup or a small company, IaaS is a great option so you don’t have to spend the time or money trying to create hardware and software. IaaS is also beneficial for large organizations who wish to have complete control over their applications and infrastructures, but are looking to only purchase what is actually consumed or needed. For rapidly growing companies, IaaS can be a good option as you don’t have to commit to a specific hardware or software as your needs change and evolve. It also helps if you are unsure what demands a new application will need as there is a lot of flexibility to scale up or down as needed.

Examples of IaaS

DigitalOcean, Linode, Rackspace, Amazon Web Services (AWS), Cisco Metapod, Microsoft Azure, Google Compute Engine (GCE)

SaaS vs PaaS vs IaaS

Overall, each cloud model offers its own specific features and functionalities, and it is crucial for your organization to understand the differences. Whether you are looking for cloud-based software for storage options, a smooth platform that allows you to create customized applications, or are wanting complete control over your entire infrastructure without having to physically maintain it, there is a cloud service for you. No matter which option you choose, migrating to the cloud is the future of business and technology as we know it, and it is necessary to be properly informed.

Resources from BMC

BMC provides multiple resources to help you gain the most from your cloud environment. Cloud Lifecycle Management is a cloud management platform that accelerates innovation through automated provisioning, governance, and management of secure cloud services. It gives users self-service access to click and deploy simple VMs or full application stacks across multiple cloud environments.

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ESG Lab evaluated BMC Cloud Lifecycle Management and found it highly effective for meeting enterprise demands for agility, security and manageability.

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These postings are my own and do not necessarily represent BMC's position, strategies, or opinion.

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Stephen Watts

Stephen Watts

Stephen Watts is an IT marketing professional based in Birmingham, AL. Stephen began working at BMC in 2012 and focuses on creating best-in-class web content.