Design of Home Networks and SMEs 14 – Data Security

I am constantly amazed at how many people (and, I must say, businesses) take a very casual attitude towards their data, rarely prioritizing some form of protection against data loss or corruption or disaster.

For an individual, it may just be a matter of years of regret if all of their computer data is lost or thrown in the trash, but for a business it can be corporate life or death. Very few organizations and fewer people regularly back up their data, and even fewer do so in a robust and secure manner.

Data loss

First, let’s address the issue of data loss and its causes:

Consider the following scenarios, which could result in data loss or corruption

  • The computer itself can be stolen or destroyed (eg by fire)
  • The data or system disk may fail and become unreadable; this can also be due to a virus or ransomware infection.
  • One or more files may be corrupted or deleted, either accidentally or deliberately (also often by viruses or ransomware)
  • A software change or user error can cause files to be accidentally encrypted or encryption access keys to be lost.

Assuming there are no backups, any of the above could mean the loss of valuable, even critical, information. Many companies underestimate the losses that follow a disaster involving significant data loss by an order of magnitude – most would not survive!

For one person, it is possible to lose all their photos, all their family emails, all their financial records and downloaded music… While not life threatening, the emotional impact could be significant and the expense (both in cash and time) to recover it could be significant, assuming it is possible.

The best way to minimize the impact of such a disaster is to keep backups.

What is a backup?

A backup is a copy of your computer’s files, kept on a separate medium. There are two different types:

1 Data backups, which typically do not include any of the applications required to access the data.

2 System ‘image’ backup, which includes all the files on the computer’s system disk and can be used to recreate the entire system in the event the computer is lost or damaged.

Data backups are usually relatively small – people are often surprised at how small they are.

System image backups, on the other hand, are usually quite large and have limited value since they can usually only be reloaded on a computer identical to the one that created them. Therefore, if you have lost your computer, the backup is of very limited use. Normally it’s only used for recovery after a hard drive failure – anything else and the image won’t work.

So, by all means keep a backup image of your system disk, in case it crashes, but better keep your system/application installation disks/licenses/keys so that applications can be reinstalled on a new machine.

Data backups are more versatile and can usually be easily uploaded back to the same or a new computer. In many cases this will work even if the new machine has a different OS than the old one (although there are limitations…).

However, there is one important criterion for a backup to be useful: it must be kept separate from the original data. There’s little point in backing up files to a drive that’s kept on or near the original computer – lose one, lose both!

Also, the backup disk should be kept disconnected from the main system, except when the backup is in progress. Why? Viruses and ransomware will affect ALL drives connected to an infected computer, making your backup unusable as well… This also applies to cloud storage: if the cloud drive is connected when the infection, it will also be infected. (and, from there, any other machine that accesses the cloud files…)

Making a backup

So: To back up your data, connect a separate disk/pen drive or link to the cloud disk, run the backup program, then disconnect the backup/cloud drive and store remotely from the original machine (ideally in a separate building).

If you feel rich enough, keep TWO backups in two different locations and update them alternately. Hopefully this will mean that at least one of them will always be available to use…

Leave a Reply

Your email address will not be published. Required fields are marked *