Service-Oriented IT Architectural Shift
A fundamental shift has emerged, driven by the ubiquity of computing devices across modern enterprise operations and the deployment of IP networks enabling distributed architecture. Information Technology per se has become commoditised, shifting technical requirements toward a service paradigm delivered over high-speed networks. Cloud computing represents the logical evolution in migrating enterprise IT toward a fully managed, service-based approach.
Cloud Layer Classifications
Abstraction of actual infrastructure resources is key to achieving the flexibility offered by enterprise cloud platforms. Cloud execution models are structured across three functional tiers:
IaaS
Infrastructure-as-a-Service: Base elements including virtual servers, high-availability storage, networking interfaces, power, and cooling infrastructure.
PaaS
Platform-as-a-Service: Application runtime platforms, integration services, deployment environments, and database management engines.
SaaS
Software-as-a-Service: Business-level software solutions, enterprise resource planning, collaboration workflows, and content services.