Data Challenges in ATLAS computing

ATLAS computing is steadily progressing towards a highly functional software suite, plus a World Wide computing model which gives all ATLAS equal and equal quality of access to ATLAS data. A key component in the period before the LHC is a series of Data Challenges of increasing scope and complexity. The goals of the ATLAS Data Challenges are the validation of the computing model, of the complete software suite, of the data model, and to ensure the correctness of the technical choices to be made. We are committed to ‘common solutions’ and look forward to the LHC Computing Grid being the vehicle for providing these in an effective way. In close collaboration between the Grid and Data Challenge communities ATLAS is testing large-scale testbed prototypes around the world, deploying prototype components to integrate and test Grid software in a production environment, and running DC1 production at 39 ‘tier’ centers in 18 countries on four continents.