Startup StorSimple is SAShaying to the cloud with a small and medium business on-premises appliance for active data storage – and bulk data banished to the cloud.

The cloud is not enough. It needs to be married to local storage in a seamless way. The idea is to have a 3-tier storage scheme with hot data stored locally and bulk data sent off to the cloud, which is treated as a remote big fat disk tier. All data is deduplicated and the appliances are optimised for particular application areas. Deduplication minimises the amount of data that has to be transferred to and from the cloud.

In general, StorSimple says, "usable storage capacity indicates the amount of data written to the system. This data may be stored locally within the integrated storage tiers or in the configured cloud storage services. The amount of data stored locally is dependent upon working set size and deduplication ratio."...

http://www.channelregister.co.uk/2010/12/07/storsimples_sashaying_to_cloud/