Software as a Service (SAAS) model- Cloud Computing Model

 Today I am going to talk about the Software as a Service (SaaS) model which is very much popular now a days. Many of the customer are using these services in modern era. So let's talk about the SaaS model in details.

What is SaaS or Software as a Service ?
Software as a service (or SaaS) is a way of delivering applications over the Internet—as a service. Instead of installing and maintaining software, you simply access it via the Internet, freeing yourself from complex software and hardware management.

Fig 1.1- Accessing software from the Cloud

SaaS applications are sometimes called Web-based software, on-demand software, or hosted software. Whatever the name, SaaS applications run on a SaaS provider’s servers. The provider manages access to the application, including security, availability, and performance.

Have a look on the below diagram showing the SaaS model which will clarify some of the doubts.
Fig 1.1- SaaS model- Cloud Computing

What are the examples of the SaaS models applications ?
Well in a SaaS model, the applications like Sales-Force, Google apps, Basecamp, Netsuits, Emails, Office automation services and many more.

SaaS model in details 
A terrific way to understand the SaaS model is through deliberating a financial institution, which protects the privacy of each purchaser whilst offering carrier this is dependable and secure—on a big scale. A financial institution’s clients all use the identical financial structures and era without traumatic about everyone having access to their personal data without authorization.
  • Software program as a provider basically extends the concept of the ASP version. The time period software as a service (SaaS), however, is normally utilized in extra unique settings:
  • While maximum initial ASPs targeted on managing and hosting unbiased software program providers. SaaS companies typically develop and control their own software program.
  • Whereas many initial ASPs offered more conventional patron-server packages, which require set up of software program on users' personal computers, SaaS answers of these days depend predominantly at the web and best require a web browser to apply.
  • While the software architecture used by maximum preliminary ASPs mandated maintaining a separate example of the utility for every business. SaaS solutions normally utilize a multitenant architecture, wherein the utility serves multiple organizations and customers, and partitions its facts as a consequence.
The giant majority of SaaS solutions are based totally on a multitenant architecture. With this version, a single model of the utility, with a unmarried configuration (hardware, network, operating gadget), is used for all customers. To support scalability, the software is hooked up on more than one machines (referred to as horizontal scaling).

In some cases, a 2nd model of the utility is installation to provide a pick institution of customers with get entry to pre-launch variations of the applications for testing functions. this is contrasted with conventional software program, wherein a couple of bodily copies of the software program for each doubtlessly of a exclusive model, with a doubtlessly one of a kind configuration, and often customised and are mounted across diverse purchaser web sites.

Even though an exception instead of the norm, a few SaaS answers do now not use multitenancy, or use other mechanism to including virtualization and to fee-effectively manipulate a large quantity of clients in location of multitenancy. whether multitenancy is a vital factor for software program-as-a-provider is a topic of controversy

Like other forms of Cloud Computing, it is important to ensure that solutions sold as SaaS in fact comply with generally accepted definitions of Cloud Computing. Some defining characteristics of SaaS include

• Web access to commercial software
• Software is managed from a central location
• Software delivered in a “one to many” model
• Users not required to handle software upgrades and patches
• Application Programming Interfaces (APIs) allow for integration between different pieces of software

Where to use the Software as a service ( SaaS) ?
Cloud Computing generally, and SaaS in particular, is a rapidly growing method of delivering technology. That said, organizations considering a move to the cloud will want to consider which applications they move to SaaS. As such there are particular solutions we consider prime candidate for an initial move to SaaS
• Applications where there is significant interplay between the organization and the outside world. For example, email newsletter campaign software
• Applications that have a significant need for web or mobile access. An example would be mobile sales management software
• Software that is only to be used for a short term need. An example would be collaboration software for a specific project
• Software where demand spikes significantly, for example tax or billing software used once a month

SaaS is widely accepted to have been introduced to the business world by the Salesforce Customer Relationship Management (CRM) product. As one of the earliest entrants it is not surprising that CRM is the most popular SaaS application area, however e-mail, financial management, customer service and expense management have also gotten good uptake via SaaS.

While SaaS is a very valuable tool, there are certain situations where we believe it is not the best option for software delivery. Examples where SaaS may not be appropriate include

• Applications where extremely fast processing of real time data is required
• Applications where legislation or other regulation does not permit data being hosted externally
• Applications where an existing on premise solution fulfils all of the organization’s needs

Software as a Service may be the best known aspect of Cloud Computing, but developers and organizations all around the world are leveraging Platform as a Service, which mixes the simplicity of SaaS with the power of IaaS, to great effect.