The Challenges of Remote Sensing Data Preservation and System Renewal during Continuous Operation

Kurzfassung

At DLR/DFD the Data and Information Management System DIMS is used for handling and archiving remote sensing data. One task of DIMS is to support ongoing and upcoming new earth observation missions, the typical lifetime of an individual mission being 5 to 10 years. New missions (like TerraSAR-X or MetOp) tend to have additional requirements with respect to the functionality of the application software but also higher requirements with respect to the performance, reliability and availability of the whole system (hardware, Commercial Off The Shelf (COTS) software and application software). The other important task of DIMS is to carefully preserve the valuable remote sensing data beyond the mission’s duration for future generations, since the earth’s surface and climate continuously change and data gathered today cannot be regained later if lost. This task is commonly known as long-term archiving. Both the continuous support of missions and long term archiving require keeping DIMS in continuous operation; at the same time hardware and COTS software have to be renewed due to limited service lifetime and to meet new reliability and performance requirements. New versions of the application software have to be brought into operation as well. The challenge is renewing DIMS hardware and software components without interrupting operations for more than a few days. A similarly great challenge is preserving the remote sensing data currently archived in DIMS (ca. 150 TByte) by migrating them to new storage media while continuously providing access.