As we all increasingly use computers as part of our lives, both professional and personal, we need to have strategies for data storage and data back-up.
There are a number of options available which allow us to store and duplicate data. Broadly speaking we can consider two main modalities of data storage and back-up; physical storage and internet based storage.
Physical Storage Options
Involves storing data onto optical media, which includes CD, DVD, and Blu-Ray. The relative advantages and disadvantages of optical media are shown below.
- Media cheap
- Blu-ray offers up to 128G capacity (SS QL 12cm)
- Requires dedicated hardware to read and write optical media
- Longevity unknown estimates from 10-100 years
- Increasingly superseded by flash based storage devices
This is a form of non-volatile memory which utilizes flash memory for storage which connects to a computer via a USB plug. Flash memory can also be found in solid state hard drives (SSDs) these allow faster access and are increasingly being used to house the OS (Operating Systen) within desktop, laptop computers, and tablets. SSDs are usually more expensive and have less storage capacity than traditional Hard Disk Drives.
- Smaller capacity drives cheap
- USB Connection Commonplace
- Can be lost easily
- Limited storage capacity
- Risk of failure
Hard Disk Drive (HDD)
Hard Disk drive are also a form of non-volatile memory which used magnetic disks and a moving magnetic head to accress and write data. They are usually contained within a computer case, but can be bought in portable cases.
- Large storage available – 3Tb Available Affordable
- Depending on set-up little or no redundancy outside of single machine
- Portable HDD same limitations as Flash Drives
- Unable to easily share data
- Risk of drive failure
- Formating can limit usability across differing OS
NAS describes a Network Attached Storage Device / Drive NAS devices have transisioned from used in commercial settings to home use suitable devices. In general terms a NAS is, as it’s name suggests, a storage device attached to a network. This configuration allows the NAS to be held separately from other network devices, if desired, and access from all computers on the network.
- Large capacity storage
- Physical separation from computer
- Allows for redundancy depending on configuration e.g. RAID O vs RAID 1
- Requires more IT knowledge to configure than other options
Internet based storage, usually referred to as cloud storage, involves data being uploaded to third party internet servers. The use of multiple server banks and data centers provides redundancy to protect the uploaded data. There are multiple cloud services available for both commercial and individual use, see here. Popular cloud services include Dropbox, Google Drive, and iCloud. Detailed comparison of these services can be found here.
The relative advantages and disadvantages of cloud storage are shown below.
- Many services free
- Allow sharing of files with multiple users
- Allow multiple users to collaborate in the same document
- Multiple platform e.g. Win / Mac OS/ Android
- Can access storage via web-based interface
- Data protected from single device failure
- Limited data storage for free
- Large files difficult to use – limited by upload / download speed
- Susceptible to cyber-crime attacks
- Unable to share across different cloud providers