For most of us when we press the delete key we feel assured that the data is no longer available. However, we all need to start thinking about where those files go after we have hit the button. If the data is not of a personal or sensitive nature then there isn’t a huge concern. However, when it comes to the disposal of the data you will need to find a better and more secure, way of erasure. So what actually happens to data after we press delete?
A common misconception is that the ‘Delete’ key erases the data, and that moving it into the recycle bin writes over the data in the file. When you select the delete key it simply just moves the file from computer to another. Deleting the file means that the space that it once occupied on the disk is free, but it will not necessarily be overwritten immediately. This will vary from disk to disk but, until it has eventually been overwritten, but it is important to note that the information can still be recovered.
So what does actually happen when you hit “delete”:
The file consists of two parts:
- An entry that makes a record of the name of the file and a list of the ‘blocks’ on the disk that contains the data within the said file. The operating system records the fact that these parts of the disk are currently in use.
2.The ‘blocks’ that actually contain the data content on the file.
When the file is deleted:
The ‘blocks’ that were recorded as containing data are now marked as ‘free,’ and will be made available for other files stored on the disk to use. The old record of the file on the disk is made available for new files to take its place, and the old file effectively ‘disappears’ from the folder.
But, be aware – the ‘blocks’ that contained the data content are not affected at all, meaning that the data within them remains until newer files eventually overwrite them – they can be recovered until they are actually overwritten.
Can you delete your files FOREVER?
It is possible to prevent the recovery of these ‘deleted’ files and to securely overwrite the data that they contain. This is usually a simple and fast task for anyone with a little computer knowledge.
However, preventing the recovery does require specific tools. It is not a suitable default task, because for this to happen by default it would be very slow and cause wear on the disk. This would also mean that, if any important data were to be deleted by mistake, it would be difficult to recover effectively and quickly.
Implementing a Secure Data Destruction Process
With GDPR coming into effect in May 2018 all businesses need to ensure that they educate staff on how to manage data. Businesses need to implement a process for the secure destruction of sensitive data that is no longer required.