Objectives Specifying all features of INFOMIX integration engine. The internal integration formalism is to be defined in a declarative way, the methods needed for its implementation are to be specified, and suitable optimization techniques are to be designed to achieve efficiency.

Description of work TASK 1: Specification of the internal integration formalism. (Task Leader UNICAL) The internal integration formalism will be defined. According to a key idea of the INFOMIX project, the formalism will be based on a declarative computational logic language, which will be suitably enriched in order to support all features of the INFOMIX Integration Information Model (IIM) resulting from Workpackage 2. TASK 2: Specification of algorithms and techniques to implement the internal integration formalism. (Task Leader UNICAL) The operational methods of the integration engine will be fully specified, providing all algorithms and techniques which are needed to realize the internal integration formalism. TASK 3: Design of optimization techniques for the internal integration formalism. (Task Leader UNICAL) Expressive languages always have a high computational complexity, which causes problems for scalability. For this reasons, efficient optimization techniques and and smart algorithms will be designed in order to efficiently support the highly expressive computational-logic formalism adopted in INFOMIX as the internal integration formalism for data integration.

Deliverables D4.1- Internal integration formalism (Report). The report will provide the declarative definition of the internal integration formalism. D4.2- Algorithms and implementation techniques for the internal integration formalism (Report). The report will specify all algorithms which are needed to implement the internal integration formalism. D4.3- Optimization techniques for the internal integration formalism (Report). The report will present the optimization methods to be employed in the INFOMIX integration engine, and will assess their suitability with respect to scalability.

Milestones and expected results M3 - Acceptance of the Integration Engine Design. The workpackage provides the detailed specification of the internal integration engine of INFOMIX. This is a critical project step, since the integration engine is the fundamental computational kernel of INFOMIX. The internal integration formalism and all algorithms and optimization techniques which are needed for its implementation will be provided.