SEAL: Common Core Libraries and Services for LHC Applications

The CERN LHC experiments have begun the LHC Computing Grid project in 2001. One of the project's aims is to develop common software infrastructure based on a development vision shared by the participating experiments. The SEAL project will provide common foundation libraries, services and utilities identified by the project's architecture blueprint report. This requires a broad range of functionality that no individual package suitably covers. SEAL thus selects external and experiment-developed packages, integrates them in a coherent whole, develops new code for missing functionality, and provides support to the experiments. We describe the set of basic components identified by the LHC Computing Grid project and thought to be sufficient for development of higher level framework components and specializations. Examples of such components are a plug-in manager, an object dictionary, object whiteboards, an incident or event manager. We present the design and implementation of some of these components and the underlying foundation libraries in some detail.