A deep archiving process now becomes one of the challenging thing that every business desire. It is because the best archival storage are able to meet all the address litigation issues and compliance requirements. Nobody wants to preserve discs spinning, serviced and powered, for up to half of the decade. Instead of disc, tape is securable and removable, but it have long-term reliability and readability concerns. Optical storage is one of the emerging choice to fill this gap. However, if someone want a long-term offline archival storage, then holographic storage can emerge as the upcoming vehicle. Because it can bring a large capacity and the media stability up to the several decades.
What is holographic storage?
A holographic storing process save data as a discrete arrangement of snapshots within the thickness of the media. The storage process starts with the splitting of a laser beam into the two signals. Among two of which one beam serves as a reference signal, whereas other beam serve to carry the and therefore, known as data-carrying beam.
The data-carrying beam passes through a fine shutter system known as spatial light modulator (SLM) device which blocks and passes both the lights at points corresponding to zeroes and ones. Within the media, the reference beam then reflects to impose on the data-carrying beam. This results in the formation of a 3D refraction pattern, also known as hologram that captured within the media. Holographic storage works by using circular media that accept spinning data along a constant spiral data pathway, like a blank DVD or CD. Once the date capture within the media in the written form, it is read back with the help of the reference beam.
The difference between the conventional DVD/CD recording and holographic storage
One of the great difference between a holographic storage and conventional DVD/CD recording is the dimensional aspect of media. In traditional types of recording, optical media write data in two dimension, like in CD or DVD using a single laser beam along a constant spiral data pathway. On the contrary, in holographic storage, data recorded within the three-dimensional media using a double beam of light that are data-carrying beam and reference beam.
A prototype holographic storage is also a kind of 3D storage system. In contrast to the traditional recording, this product can save up to one million pixels data at once. It works by storing the date in the form of discrete snapshots which is also known as pages. It forms microscopic cones within the thickness of those kind of media that are light-sensitive in nature.
Holographic storage: what is now and what will be in the future
Nowadays, holographic storage has become a Worm technology in the categories of data storing systems. It depend on the light-sensitive media that housed in a removable protective cartridges. A holographic media can save more than 4.4 million individual pages or the discrete snapshots on a disc. Hopefully, you will see rewritable drives and media very soon within the next few years. It will be more like as the progression from DVD-R to DVD-RW or from CD-R to CD-RW.
On the plus point of holographic storage is its long-term media reliability and stability. It is one of the convincing advantage of 3D storage that you can use for the deep archiving purpose. In contrast, tape and discs can assure the reliability less than 50 years.
Holographic technology also the best for the portability. It allows the distribution of compressed data that are difficult to send over the networks, such as high-definition or broadcast video.
The technology is also more compelling for shorter term archives and backups. Only a few companies keep relying on traditional type tape backups. Instead, they uses holographic storage technology attached to a VTL (virtual tape library) system as a replacement of tape alone.
On the downside, early holographic storage drives will run in the £10,000 range, with media costing about £100 per disc. Holographic media capacity is also limited to about 300Gbytes. While this capacity is expected to grow substantially over time, it’s hard to make a case for a 300Gbyte optical disc against readily available 1Tbyte hard drives or 1.6Tbyte (compressed) LTO-4 tapes without a specific application. Furthermore, the long-term reliability and readability of holographic drives is still unproven.