Metadata for efficient, secure and extensible access to data in a medical grid

We present the metadata usage in a medical imaging project grid. Metadata represent data about the data: In our case, the data are medical images and the metadata store relative information on the patient and hospital records, or even data about the image algorithms used in our application platform. Metadata are either static or dynamically constructed after computations on data. We show how the metadata is used, produced and stored to provide a secure and efficient access to medical data (and metadata) through a dedicated architecture. Experiments include times to access data and to secure the transactions.