There are three basic Cloud Service categories:
. Infrastructure as a Service (IaaS)
. Software as a Service (SaaS)
. Platform as a Service (PaaS
IaaS is the basic virtualized computing services available in the Cloud, including processing, memory and storage capabilities.
SaaS is the use of application software, which is hosted in a cloud environment. Additionally the software is structured so many different users can use it concurrently. Examples include hosted email, and Customer Relationship Management (CRM) software.
PaaS is the idea of providing a software development, application or industry specific “framework” for users to develop their own software. Similar to SaaS, these frameworks are hosted in the Cloud and are multi-user. Examples include: Google App Engine and Microsoft Windows Azure.
In the marketplace today, these services are at different levels of their growth and maturity. SaaS is the most mature, partially because the delivery of application software over the Internet, at scale to thousands over customers, has been occurring for many years. IaaS is the next mature, pioneered by Amazon and now being delivered through multiple technologies by a number of companies. PaaS is the least mature, mostly because of the nature of the software that is being hosted (i.e. good application and/or industry frameworks are in-of-themselves a more difficult undertaking).
The next blog will be a discussion of IaaS technologies.