Ben Webber, an analyst with our Data Discovery and Analytics team, explores the advantages of Solid State Drives, not just in performance terms but also helping to maximise analysts' valuable time.
As technology has improved within the IT industry as a whole, something that has been a real game changer has been the introduction of SSDs (Solid State Drives). Typically, before this HDDs (Hard Disk Drives) have been used for all storage, in a non-volatile state. SSDs are effectively the upgrade to HDDs, their only real draw back is that they are slightly more expensive, which is normally the first thing that people and companies address when it comes to equipment.
So, what are the differences between these two storage types? HDD is pretty much exactly as it sounds; it is an array of hard disks that can be written to and read. Normally they can be rewritten to multiple times but in some specialised cases they are not optimised for this. For the HDDs to work they must physically spin up, and their speed is a large factor in how fast they can be written to and read. This means that there are obvious limitations and also other factors that HDDs normally have to adopt, such as typically having a larger form factor.
SSDs on the other hand have none of these drawbacks. They do not have any moving parts, they are in fact just a circuit board, made up of semiconductor cells which can hold between 0 and 4 bits. These cells will hold their charge even when the device has been powered off, hence why it is a non-volatile form of data storage. The circuit it tightly compacted with these cells and they continue to improve on newer models, holding more and more cells which are even smaller. All of this means that data can be transferred, written and read at incredibly fast speeds!
Something that people sometimes talk about when using SSDs and say that HDDs have the advantage in, is the fact that SSDs have something called bit rot. This is when cells on the SSD have been written and read many times and eventually those cells die and cannot be used anymore. No data is lost with this process because as soon as a cell suffers bit rot the data is placed to a new cell. HDDs on the other hand obviously cannot get bit rot. Instead, they can just generally break from many other reasons during regular use - for example, heads getting stuck, dust/dirt getting trapped inside or just general damage from being knocked around.
But there’s a bit of a misconception here. The fact is that SSDs having bit rot actually makes them much more reliable and predictable. Bit rot happens at a very slow rate and the drive itself can be detected for this, which means you can get an accurate survival time of the drive. HDDs, on the other hand, because they do not have a consistent measure for something like this are normally predicted off their maximum potential endurance, mainly as a marketing ploy, when really, they very often break much faster than this.
All these things considered; it is then clear why SSDs should be a much better choice than HDDs. Applying this to a digital forensic company situation the benefits become clear instantly. From personal practice, when doing something like imaging or processing data it significantly reduces the time that is required to complete the process.
Processing using a tool like Nuix, if the data is stored on an SSD and then the whole operation is run on an SSD also, the time processing, examination, exporting etc is incredibly quick. There is no comparison between HDDs and SSDs in that regard. This means that jobs can be taken on and completed very rapidly and as a result means that the tools and licences are being utilised to a much greater potential, and returning more value. So, any money that is used to purchase the SSDs in the first place will be made back rapidly and then technically create even better value. It is the best way to utilise the company equipment, making everything more efficient.
This paired up with the advantages an SSD already brings such as a small form factor (so easily stored/handled/removed) makes the winner of this competition very clear. The main factor is still always going to be price, but this gap is rapidly closing and in now quite a few cases, it’s cheaper to use an SSD.