Secondary Storage(Optical, Magnetic, Solid-state and Cloud) Flashcards
What is secondary Storage?
A non-volatile long-term storage which is not directly connected to the CPU
Factors which effect storage
Capcity
Cost
Portability
Durabilty
Speed
Reliablity
What is the 3 types of secondary storage
Optical
Magnetic
Solid State Drive
how does optical storage work?
Binary data stored as variations of height on the disk’s surface
To read the data light is shined on the disk: light that hits a land reflects differently to where it hits a pit
Data is writtent with a laser “Burning” the pits into the disk
What are the optical storage stats?
Per unit, small capacity(Most CDs < 1GB capacity)
Fairly reliable and durable but can be easily damaged like Scratches etc…
Good portabilty- easy to transport and carry
How does magnetic storage work?
Use read/write heads that contain electromagnets
Parts of the surface is either magnetised(1) or demagnetised (0) and the heads control this and read what state they are in
What are the Magnetic storage stats?
Large capacity and cheap to buy
Usually reliable but not that durable
Generally not very portable
can be noisy and generate heat
How does SSDs work?
Form of flash memory so non-mechanical
Consists of digital circuits that retain data which can then be changed
What are the SSDs stats?
Very fast for storage but expensive
Very reliable as they are non-mechanical
Don’t need defragmentation
Generally have a smaller capacity than magnetic
Silent
What is cloud storage?
Where data is stored on multiples servers in a remote location
How does cloud storage work?
Servers use magnetic and now increasinggly solid-state storage
Generally operates through a web-based API
What are the SSDs stats?
Versions are kept(so durable), but service may not be reliable
Portable - files can be accessed from anywhere on the internet
For larger companies may be cheaper(reduced eenergy cost), but likly more expensive for smaller users
