| I assume that this is write-once memory. When cheap enough, write-once memories are much preferable over read-write memories, for archival and backup purposes. Magnetic tapes are also normally used as append-only memories and very infrequently, if ever, they may be completely erased in order to reuse the cartridge and avoid buying a replacement. While it is possible to use a magnetic tape like you would use a HDD, erasing and writing at random positions, there is no reason to do that, because it would be slow and it would not use fully the capacity of the tape. It is likely that this holographic memory will be used exactly like a tape, i.e. append-only, but it will not be possible to erase the holographic cartridge. If it would be possible to erase it, I would consider that as a deficiency, by providing an almost useless feature, which must be paid by a lower lifetime, as any material whose properties are reversible is much more likely to lose the information in time. |