In backups, it often happens that the full day-to-day backup leads to an inflation of the data pool. If the set of band media is reused after a week, the amount of data quintupled. As the data amounts crow constantly, a change in strategy needs to take place avoid that the costs, wear, amount of time and the load for the productive network becomes too large. With the publication of the ADSM-Backup-Software IBM developed a new data backup strategy. There was a one-off full backup, afterwards only the incremental changes were stored.