HDS' has a new virtual tape product that the company claims is able to discard up to 96 percent of duplicated backup data. Virtual tape products store backup data on disk and emulate a tape library so that backup applications continue unchanged. Data is backed up and restored at disk speed, many times faster than tape.

Quantum's ADIC, EMC, HP and others already supply virtual tape products. What makes HDS' Virtual Tape Library more than just a 'me-too' product is that it uses products and technology from Diligent Technologies with seemingly remarkable data de-duplication capabilities. The ProtecTIER de-duping engine is called HyperFactor and it replaces duplicated data with pointers. This shrinks the data to be stored by a factor of 25 or more, meaning only 4 percent or less of the backed up data physically needs to be stored on disk.

HDS CTO Hu Yoshida said Diligent has "technological leadership - particularly in the field of data de-duplication, leading to (a) dramatic reduction in required storage capacity - and future road map potential."

Existing Diligent customer deployments realise 10:1 to 25:1 data de-duplication ratios and have sustained throughput of 200MB/s. One customer stores 880TB of raw backup data on just 40TB of disk, a 22:1 compression ratio.

The stored data index, used for the byte-level comparison, is mapped at a ratio of 250,000:1. It means that a 1PB repository of de-duplicated or compressed data can be mapped into a 4GB index which is stored in RAM. The comparison is done in real time, without reference to disk, making it very fast. Incoming data is compared to the index to find similar patterns, looking for matches at various data element sizes. When found the similar data is then fetched from the repository and byte-level differences between it and the incoming data found and stored.

HDS will supply both mainframe (VTF Mainframe) and open systems (VTF Open and ProtecTIER VT) virtual tape products together with a backup assessment service. No pricing information was released.

Co-incidentally Sun is set to abandon its open systems virtual tape development project.