INPUT OUTPUT AND STORAGE Flashcards
(11 cards)
Describe the suitability of a flash storage device and a magnetic storage device.
Magnetic Benefits:
- Lower price per GB
- As standard comes in high capacity
Magnetic Drawbacks:
- Lower R/W speed
- Higher power consumption
- Moving parts / less durable
- Magnetic hard drives can be noisy (due to parts moving at high speed)
Flash Benefits:
- Higher R/W speed
- No moving parts / more durable
- Lower power consumption
- Can have a higher capacity
- Operate silently
Flash drawbacks:
- Higher cost per GB
- At higher capacities prices rise exponentially
- Smaller capacity (in comparison)
- Limited lifespan due to limited read/writes
Explain why virtual storage is well suited for storing backups
- Stored away from the computer
- So in case of disaster, data is not also damaged
- All of the data (from multiple machines) can be backed up at the same time
- Can be accessed from elsewhere / other machines
- Storage can be expanded as necessary / no limit on size
- Speed off access is not a priority for backup
- Can make recovery from another site easier
- No physical space needed for backup hardware
- No on site maintenance required
- Allows more logical storage capacity for data
Define magnetic storage
- Magnetic devices include magnetic hard drives and magnetic tape
- Data stored by altering the magnetic field of a small section of tape or disk
- One orientation represents a binary value of 1
- The opposite orientation represents a binary value of 0
- Written to using a read/write head
- Read/write head can then read the magnetic field and retrieve the data
- These read and write heads move across the disk or the tape moves under the heads.
Define solid state storage
- Solid state devices store data using semiconductors
- Forming the logic gates NAND and NOR to store electrical charge in one of two states: high or low
- These two states represent the binary values
- Information is stored in blocks, which are combined to form pages
- The preferred logic gate used for storing small quantities of data is NOR
- For larger files, NAND is the preferred technology
What is a backup
Copying potentially large amounts of data to and froms storage devices at regular intervals
Give one disadvantage to the user of using cloud storage
- Potentially vulnerable to hacking
- Reliant on internet connection / requires a fast enough internet connection
- Reliant on company servers
State input and output devices:
Input:
- Microphone
- Buttons
Output:
- Speaker
- LEDs
- Screen / Monitor
- Printer
State types of storage devices
- External hard disk
- SOlid state drive
- Flash memory card / stick / drive
- SD card / Micro SD card
- USB stick
Define optical storage
- A laser is shined on the spinning disk
- The reflection from the media is processed
- The surface of the disk is physically burnt by the laser, creating pits and lands, suitable for storing 0s and 1s
-It is the point where the pit starts or ends which causes the laser light to scatter, and thus is not reflected as well - The change in reflection is interpreted as 0s and 1s
Describe the advantages and disadvantages of optical storage
Advantages:
- Cheap
- Lightweight
- Portable
- Easy to mass distribute
Disadvantages:
- Slow access times as data is read and written in a spiral from the inside to the outside of the disk
- Prone to scratches
- For readable disks, once the surface has been burnt, it cannot be changed
What is virtual storage
- The concept of storing and retrieving data over the internet in the cloud instead of a local storage device
- The abstraction or separation of logical storage from physical storage (The user perceives a single storage area neatly structured and organised under a single drive but the physical implementation could have the files stored across different media)
