Data Deletion with Time-Aware Adversary Model

In our paper we generalize and extend model of storing data on magnetic drives. This model allows to erase data from magnetic drives even in the presence of a very strong adversary that can read the old data overwritten arbitrary number of times. However, from the physical point of view the adversary can be even more powerful, e.g. in addition be can be able to determine the order in which bits were stored. Such an assumption in the case of very well equiped adversary trying to retrive important data can be realistic. For that reason we introduce an extended model of the adversary, that we called time-aware adversary model. We show that the solution for secure data deletion from is not suitable for the time-aware model, i.e. the adversary can reconstruct whole data stored on a magnetic drive with high probability. We investigate time-aware model and its properties and propose some solutions which (to some extent) allow provable deletion in newly introduced model.