What is SAAS in Cloud Computing

How does software as a service work?

It works through the cloud delivery model. A software provider will either host the application and related data using its own servers, databases, networking, and computing resources, or it may be an ISV that contracts a cloud provider to host the application in the provider’s data center. The application will be accessible to any device with a network connection. SaaS applications are typically accessed via web browsers.

As a result, companies using SaaS applications are not tasked with the setup and maintenance of the software. Users simply pay a subscription fee to gain access to the software, which is a ready-made solution.

SaaS is closely related to the application service provider (ASP) and on-demand computing software delivery models where the provider hosts the customer’s software and delivers it to approved end-users over the internet.

In the software-on-demand SaaS model, the provider gives customers network-based access to a single copy of an application that the provider created specifically for SaaS distribution. The application’s source code is the same for all customers, and when new features or functionalities are released, they are rolled out to all customers. Depending on the service-level agreement (SLA), the customer’s data for each model may be stored locally, in the cloud or both locally and in the cloud.

Organizations can integrate SaaS applications with other software using application programming interfaces (APIs). For example, a business can write its own software tools and use the SaaS provider’s APIs to integrate those tools with the SaaS offering.

SaaS architecture

It applications and services typically use a multi-tenant approach, which means a single instance of the SaaS application will be running on the host servers, and that single instance will serve each subscribing customer or cloud tenant. The application will run on a single version and configuration across all customers or tenants. Though different subscribing customers will run on the same cloud instance with common infrastructure and platform, the data from different customers will still be segregated.

The typical multi-tenant architecture of SaaS applications means the cloud service provider can manage maintenance, updates, and bug fixes faster, easier, and more efficiently. Rather than having to implement changes in multiple instances, engineers can make necessary changes for all customers by maintaining the one, shared instance.

Furthermore, multi-tenancy allows a greater pool of resources to be available to a larger group of people, without compromising important cloud functions such as security, speed, and privacy.

advantages

It removes the need for organizations to install and run applications on their own computers or in their own data centers. This eliminates the expense of hardware acquisition, provisioning, and maintenance, as well as software licensing, installation, and support. Other benefits of the SaaS model include:

• Flexible payments. Rather than purchasing software to install, or additional hardware to support it, customers subscribe to a SaaS offering. Transitioning costs to a recurring operating expense allows many businesses to exercise better and more predictable budgeting. Users can also terminate SaaS offerings at any time to stop those recurring costs.
• Scalable usage. Cloud services like SaaS offer high Vertical scalability, which gives customers the option to access more or fewer services or features on-demand.
• Automatic updates. Rather than purchasing new software, customers can rely on a SaaS provider to automatically perform updates and patch management. This further reduces the burden on in-house IT staff.
• Accessibility and persistence. Since SaaS vendors deliver applications over the internet, users can access them from any internet-enabled device and location.
• Customization. It applications are often customizable and can be integrated with other business applications, especially across applications from a common software provider.

SaaS vs. IaaS vs. PaaS

SaaS is one of the three major cloud service models, along with IaaS and PaaS. All three models involve cloud providers that deliver their own hosted data center resources to customers over the internet.

Where the models differ is in the completeness of the product. SaaS products are complete and fully managed applications. IaaS is largely outsourcing data center resources, and PaaS delivers a development platform and other tools hosted by the provider’s data center.

SaaS application users do not have to download software, manage any existing IT infrastructures or deal with any aspect of the software management. Vendors handle maintenance, upgrades, support, security, and all other aspects of managing the software.

IaaS is used by companies that want to outsource their data center and computer resources to a cloud provider. IaaS providers host infrastructure components such as servers, storage, networking hardware, and virtualization resources. Customer organizations using IaaS services must still manage their data use, applications, and operating systems (OSes).

PaaS provides a framework of resources for an organization’s in-house developers. This hosted platform enables developers to create customized applications. The vendor manages the data center resources that support the tools. Customer organizations using PaaS services do not have to manage their OSes but must manage applications and data use.