1. A method of providing data backup, the method comprising: receiving at a virtual tape backup system a tape image to be maintained; performing a cryptographic operation on the contents of the tape image and distributing the contents of the tape image in a plurality of secondary data blocks based on a key, wherein each of the plurality of secondary data blocks contains a random or pseudo-random distribution of a respective subset of the tape image, and wherein the key is usable to determine into which of the plurality of secondary data blocks each unit of the tape image is placed; and storing the plurality of secondary data blocks in a plurality of shares located on a plurality of physical storage devices of the virtual tape backup system by accessing one or more logical mount points that point to the plurality of physical storage devices, whereby the tape image is restorable from a threshold number less than all of the plurality of shares.