What is Software as a Service (SaaS)?

Software as a Service (SaaS) is a software distribution model in which a cloud provider hosts applications and makes them available to end users over the internet. In this model, an independent software vendor (ISV) may contract a third-party cloud provider to host the application, or the cloud provider may also be the software vendor.

SaaS is one of the main categories of cloud computing, alongside Infrastructure as a Service (IaaS) and Platform as a Service (PaaS). SaaS applications cater to a wide range of users, from IT professionals to personal users, and are marketed to both B2B and B2C markets.

SaaS Architecture

SaaS applications typically use a multi-tenant approach, where a single instance of the application serves multiple subscribing customers or cloud tenants. This shared instance allows for efficient management of maintenance, updates, and bug fixes by the cloud service provider.

The multi-tenant architecture ensures that each subscribing customer's data is segregated, while they all run on the same instance with a common infrastructure and platform.

Advantages of SaaS

SaaS offers several advantages over traditional software deployment models:

• Flexible Payments: Customers subscribe to SaaS offerings, allowing for better and more predictable budgeting. Recurring costs can be terminated at any time.
• Scalable Usage: SaaS provides high vertical scalability, allowing customers to access more or fewer services on demand.
• Automatic Updates: SaaS providers handle updates and patch management automatically, reducing the burden on in-house IT staff.
• Accessibility and Persistence: SaaS applications can be accessed from any internet-enabled device and location.
• Customization: SaaS applications are often customizable and can be integrated with other business applications.