Storage & Backup

Storage & Backup

Physical Storage Devices (also known as 'Local Data Storage'):

RAM – Random Access Memory.  It holds program code during computation; in other words it stores the programs that you have open and running on the computer. It is volatile (Primary storage) storage.  Volatile means that once turned off the storage is emptied.  DDR, RD RAM are now used.

ROM – Read only Memory, cannot be written to.  It is non-volatile and be used to store boot information.

Hard Drives:

• Internal (HDD, HD) are non-volatile, they store all programs and data. 
• External hard drives are often used as back up device; they are portable and can be stored securely

Magnetic Tape (an example are DAT Tapes).  Is read sequentially (think of old 'tape' or 'Video Cassettes' where you had to fast forward to find a particular song/part of the film).  It is used as backup medium.  It will eventually fade out as HDD become more widely used; but currently we still use these at school for backup on a daily basis.

Flash Memory / Card  these are used everywhere (phones, mp3, games consoles etc).  They are highly portable and can be often overwritten.  They come in lots of different formats and sizes

Online Storage (also known as 'Cloud Storage')

Online data storage is where your files are stored on a server elsewhere which you access using the Internet. This is known as 'on the cloud'.  There are advantages and disadvantages of cloud storage:

Advantages:

• The data is available anywhere you have the Internet access and and a browser
• There are quite a few online storage services that are free (obviously a business user would need a lot of storage space and therefore charges would be involved)
• It is easy to shared you data with others (for example the IT teachers share a drop box storage area for the IT teaching resources)
• Data is backed up for you.

Disadvantages:

• You have to trust the organisation that you are using to store your data (will they keep it secure; could they cease operating overnight and you not be able to access your data?)
• The data storage area may not be reliable
• You need and internet connection to access your data (you may not always have access)
• You have less control over your own data, you are putting it in someone elses hands and you have no idea where it is being stored.

Lots of companies are now using online storage for their data storage needs.

Backup

Files can be lost from your computer in any number of ways—you might accidentally delete a file, or a virus might wipe one out. You can also have a complete hard drive failure. Important personal items are usually gone forever—family photos, significant documents, downloaded music, and more.

Thankfully it's a really simple process these days to back up your content to a second, separate location. By doing so, your files can be protected against viruses or complete computer failure. This makes it easy to retrieve and place them on a new hard drive and get going again.

There are many options for backing up your data. You can use CDs, DVDs, external hard drives, flash drives, network drives, or even online storage. It might be a good idea to back up your data to multiple places. For example, you might choose to back up your content onto both an external hard drive and to an online storage site.

Companies have to ensure that they regularly backup their systems.  This is usually done on a daily basis.  The media on which the backup is on has to be stored in a safe place (this might mean in a bank vault, or as we do at school in a fire proof safe).  Companies will have a disaster recovery plan.  If there were to be a disaster, such as fire etc they have to be able to set-up a temporary company and get operating as soon as possible to ensure that the company remains in business; the first key point to a disaster recovery plan is to have an up-to-date backup of all your data and systems.