What’s the difference between SaaS, PaaS, and IaaS?

Technology has evolved rapidly in recent decades. Dipping computer and server hardware prices led to the introduction and adoption of modern cloud computing. Models such as software as a service (SaaS), platform as a service (PaaS), and infrastructure as a service (IaaS) have emerged largely as a result of the desire to harness the computing power of a grid (a network of servers).

Such intertwined technologies are often confused. This article will explore the idiosyncrasies, benefits, and drawbacks of SaaS, PaaS, and IaaS models.

Software as a Service | SaaS

Software as a service is a software licensing and delivering model that has gained significant traction in a number of applications from corporate to business, scientific, and even commercial. SaaS allows users to access proprietary software on a subscription basis (typically month-to-month or annual).

SaaS is an enormously cost-effective alternative to on-premise software installations and management. The SaaS model can deliver anything from construction planning software, property tax management, payroll and accounting, human resources management, and more.

SaaS revenue worldwide amounted to $79 billion in 2016. Statista predicts by 2027, worldwide SaaS revenue will hit $346 billion. As of 2018, SaaS accounted for approximately two-thirds of the revenue of the cloud computing market.

The SaaS model comes with lower up-front costs and zero licensing fees, making it extremely cost-effective. This is especially advantageous for startups and small businesses as it effectively minimizes the expense of establishing and scaling a business rapidly.

The provider manages the infrastructure running the software, shouldering hardware and support expenses. Reduced fees for hardware and software maintenance provides an enormous economic advantage.

Technology has long been considered a hassle, with an immense learning curve, often requiring expert assistance for set-up and ongoing maintenance. SaaS evades this issue, by minimizing downtime and delays. This is possible because SaaS apps are configured on remote servers (the cloud).

Additionally, SaaS models tend to have a shorter learning curve that drives engagement and increased productivity. This reduces the need for ongoing training and increases the overall return on investment for the software. With the end-user not having to directly manage or maintain complex server or software setups, the business owner is freely able to allocate their time to more pressing issues.

Upgrades and installation are an enormous pain. Potentially substantial downtime combined with strenuous, required labor hours makes for a headache. The SaaS model removes concerns by automating upgrades.

As SaaS service providers typically roll-out upgrades via centrally-hosted applications, previous headaches become a smooth, uninterrupted transition. This promotes user convenience and overall productivity. Additionally, this increases security and reduces vulnerability with the automatic roll-out of patches and updates.

Choices can elevate the appeal of software to customers and users, and typical SaaS models have no shortage of options. These models allow users to scale up or scale down their engagement, as aligned with business needs. A variety of subscription packages provide additional flexibility.

Further, SaaS applications can typically be accessed anywhere with a browser and internet access — phones, laptops, tablets, and more. This gives users the flexibility to use software from virtually anywhere, starkly contracting typical installation-based software that can only be used from a single device.

The main challenge of SaaS models is the ever-present vulnerability. These applications are at risk of unauthorized access and hacking. While cost-effective for small businesses, these vulnerabilities can prove detrimental, as cybercriminals can disseminate a cloud-operated business by blocking employees’ and customers’ access to mission-critical online systems. As a result, service providers must continually invest in improving security and assuring customers’ safety. Potential internet outages are also an additional concern for organizations that cannot afford downtime to clients.

Platform as a Service | PaaS

Platform as a service is a category of cloud services that provide a platform allowing customers to manage, run, and develop applications without complexity typically associated with application infrastructure. PaaS services consist of hardware and software hosted by the provider. This removes the need to install in-house hardware.

This cloud-computing model is increasing in prevalence as it reduces set-up costs and maintenance-associated expenses. This reduces the barrier to entry, giving users access to resources that would otherwise be out of reach due to budget restrictions.

PaaS-based systems give developers significant control over custom configurations. This preserves the goals of the original development work. PaaS providers handle application execution, data, and underlying system functionality.

Additionally beneficial for coders and developers, providers offer the use of individual development tools, frameworks, and other relevant resources, configured for use in the provider’s platform.

In today’s day and age, developing applications for multiple platforms is crucial. PaaS vendors make it easy to develop applications for use on different devices, such as phones or desktops. This is a quick and inexpensive way to scale an application.

As with SaaS models, PaaS technologies are incredibly scalable. As a result, these services generate substantial cost-savings for developers, allowing them to increase margins and gain traction quickly.

Most importantly, the scalable nature of PaaS models allows project scope to expand in conjunction with market demands, allowing developers to stay competitive in the industry.

PaaS technologies reduce the amount of coding required to develop and execute an application. These services also help automate business policy, driving process efficiencies. With 99.9999–99.999999% uptime and the ability to accommodate multiple digital tenants, these technologies drive the migration of apps to the hybrid model of cloud computing.

Utilizing PaaS technologies eliminates the need to hire skilled staff or outsource specific activities. This gives in-house developer teams new capabilities with strenuous tasks moved off their plate.

Keeping up with the latest trends and technology is hard enough without considering all that goes into developing an application. Quicker development and deployment is a significant benefit, drastically reducing the overall app development lifecycle.

PaaS technologies pose particular risks for service providers, including balancing control, costs, and capacity of a PaaS-based service. Providing full multi-tenancy support and integrating third-party services creates additional challenges.

Once selecting a PaaS, it can be difficult to switch to a different vendor. Typically, when developing on these platforms there is a specific set of tools and capabilities. For example, not all vendors will support all APIs, coding languages, operating systems, and more.

Infrastructure as a Service | IaaS

Infrastructure as a service is the virtual delivery of computing resources via hardware, networking, and storage service. Instead of making the steep investment of purchasing and implementing necessary resources in a data center, companies are able to rent or lease these resources on an as-needed basis.

IaaS operates via traditional cloud infrastructure. Service providers host a variety of infrastructure, including service, storage, networking hardware, and more. This opposes the longstanding business case for investing in on-premise resources, data center infrastructure, and equipment. Additional services include performance monitoring, digital security, data backup, virtualization, and more.

IaaS is typically paid on a per-seat basis, but can sometimes be negotiated as hourly, weekly, or monthly rates. This method evades steep up-front costs of on-premise hardware and software. IaaS creates an incredible opportunity for organizations to utilize infrastructure that would typically be out of their reach.

Similar to SaaS and PaaS models, IaaS provides tiered pricing and easy scaling. This attracts a variety of customers with varying needs and creates an opportunity to scale up with clients as they grow in size.

Being hosted on the cloud, IaaS is entirely location-independent. Additionally, redundancy ensures your infrastructure is protected in the event of a natural disaster or significant weather emergency at one data center. Instead of relying on populating a backup from a remote server — or worse an on-premise server — employees and clients alike can access everything from wherever they are, via an internet connection.

A large challenge of IaaS models is managing subscriber expectations. There is a surplus of misconceptions associated with cloud computing and its capabilities, making it necessary for IaaS providers to educate around those myths and clear up any confusion.

Additionally, an ever-evolving market necessitates ongoing, agile experimentation. Don’t wait for the next big thing to happen, be the one to bring a new concept to light.


The constantly changing nature of technology has generated a surplus of new opportunities to access state-of-the-line software, hardware, and infrastructure without needing to make a full purchase. Instead, users are able to scale their services to accommodate their needs at any given time. These are optimal for scaling businesses and planning for future growth.

Security vulnerabilities are a larger concern for software as a service models. Providers need to pay special attention to ensuring these concerns are evaded and customers are put at ease. Handling customer expectations, multi-tenancy support, and an industry full of expectations are just a few challenges facing PaaS and IaaS models.

With the adoption of any new technology, precautionary measures should be taken before implementing any radical overhauls to infrastructure systems. All three of these distinct technologies have the capabilities to improve upon day-to-day use at a high caliper. Companies should explore how these technologies can improve their efficiency and efficacy while saving money, experiencing improved support, and more.

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