Software as a Service (SaaS)

enables users to access applications running on a Cloud infrastructure from various end-user devices (generally through a web browser). The user does not manage or control the underlying Cloud infrastructure or individual application capabilities other than limited user-specific application settings.

 

Software as a Service, SaaS, sometimes referred to as "software on demand," is software that is deployed over the internet and/or is deployed to run behind a firewall on a local area network or personal computer. With SaaS, a provider licenses an application to customers either as a service on demand, through a subscription, in a "pay-as-you-go" model, or (increasingly) at no charge when there is opportunity to generate revenue from streams other than the user, such as from advertisement or user list sales. This approach to application delivery is part of the utility computing model where all of the technology is in the "cloud" accessed over the Internet as a service.

Advantage

• Accessible from anywhere with an internet connection
• No local server installation
• Pay per use or subscription based payment methods
• Rapid scalability
• System maintenance (backup, updates, security, etc) often included in service
• Possible security improvements, although users with high security requirements (e.g., large corporations) may find SaaS a security concern
• Reliability

SaaS has become a common model for many business applications including accounting, collaboration, customer relationship management (CRM), enterprise resource planning (ERP), invoicing, human resource management (HRM), content management (CM), and service desk management.

Key characteristics

• Network-based access to, and management of, commercially available software
• Activities managed from central locations rather than at each customer's site, enabling customers to access applications remotely via the Web
• Application delivery typically closer to a one-to-many model (single instance, multi-tenant architecture) than to a one-to-one model, including architecture, pricing, partnering, and management characteristics
• Centralized feature updating, which obviates the need for end-users to download patches and upgrades.
• Frequent integration into a larger network of communicating software—either as part of a mashup or a plugin to a platform as a service.

Benefits

• Capital expenditure is reduced by not having to purchase servers or full copies of software. This is counterbalanced by the increased revenue cost of paying for the use of the SaaS.
• Faster implementation. In some cases the customer can deploy SaaS more quickly as no local installation is required.
• Depending on the user, it may remove a non-core activity (deployment and support of the software and its associated infrastructure) freeing up time to focus on core business activities.
• Reduced need to predict scale of demand and infrastructure investment up front.
• Possible improvements to reliability if the SaaS provider's infrastructure is more redundant or has higher availability than the user would otherwise have.