I just finished reading (a white paper) about SaaS from Gianpaolo Carraro and Frederick Chong, both architects in Microsoft. SaaS is quite popular these days supporting, supplementing and extending the previous "king" of architecture discussions, SOA. The paper introduces quite well the concept of SaaS in terms of Business, Technical, Architectural and Operational aspects and requirements. Among other talks about :
  • SaaS definition
  • SaaS categories (Consumer, Line of business)
  • Business model (The Long Tail effect)
  • 3 main attributes of SaaS (scalable, multi-tenant efficient, configurable)
  • SaaS maturity model
  • High level architecture (Interface, Business Logic/Rules, Data issues)
  • Operational aspects
The paper is supported by a chat published in MSDN. Except traditional ISVs, this model may be quite attractive for enterprises interested in offering SaaS to their subsidiaries or to their franchisees. The whole thing seems quite interesting and promising, however there are certain challenges as expressed in Don Dodge's post such as :
  • Initial investement
  • Pricing and cashflow
  • Sales compensation
  • SLAs and Legal issues
  • Hosting
  • Complex technical development environment
The important thing is that the discussion has already started, service provider companies as well as technology provider companies currently are investing and for sure it's worth to keep an eye on this.