The three major subsystems - Data Integration Services, Decision Repositories, and Decision Services - are part of an information supply chain. Data starts in raw form, goes through transformations, storage, distribution, and packaging until it reaches the final consumer. All three are needed to support pervasive BI.
Pervasive BI exposes a need that was often not present in traditional BI - SLAs in all three subsystems. This is because the front-line user has near real-time performance expectations, 24 hours per day, and 365 days per year. It is irrelevant to the call center or web site consumer what part of the infrastructure is failing or slow. Thus, the critical success factors focus on formal SLAs for:
- Data freshness, cleansing, accuracy, and completeness.
- Scalability in terms of concurrent users by delivery mechanism.
- Mixed workload management to ensure service level performance goals.
- Tactical query response time measures by type of user and analytic.
- High availability metrics by user community and delivery mechanism.
Data Management Research Library 
