Digital Storage: Preserving Content Locally and on the Cloud

Module 8: Digital Storage - Preserving Content Locally and on the Cloud

Objectives Overview 1 of 2

  • Differentiate between storage and memory
  • Describe characteristics of internal hard disks
  • Describe benefits of solid-state drives (SSDs)
  • Identify uses of external hard drives and RAID systems
  • Differentiate among various types of memory cards and USB flash drives

Objectives Overview 2 of 2

  • Discuss benefits and uses of cloud storage
  • Describe characteristics of and differentiate among types of optical discs
  • Explain types of enterprise storage
  • Identify uses of magnetic stripe cards, smart cards, RFID tags, and NFC tags

Understanding Storage

  • Storage Medium: The physical material on which a computer keeps data (e.g., internal hard drives, external drives, cloud storage).
    • Cloud Storage: Keeps information on internet servers, making the storage media transparent to the user.
  • Storage Device: The hardware that records and/or retrieves items from the storage media.
Capacity of Storage
  • Capacity refers to the number of bytes a storage medium can hold.
  • Common storage terms and their capacities:
    • Kilobyte (KB): Approx. 1,000 bytes
    • Megabyte (MB): Approx. 1 million bytes
    • Gigabyte (GB): Approx. 1 billion bytes
    • Terabyte (TB): Approx. 1 trillion bytes
    • Petabyte (PB): Approx. 1 quadrillion bytes
    • Exabyte (EB): Approx. 1 quintillion bytes
    • Zettabyte (ZB): Approx. 1 sextillion bytes
    • Yottabyte (YB): Approx. 1 septillion bytes

Volatility of Data

  • Volatile Storage: Loses data when power is removed (e.g., RAM, screen displays).
  • Nonvolatile Storage: Retains data without power (e.g., hard drives).

Access Time

  • Measures the time taken to locate and deliver items from storage.
    • Memory is faster but more expensive compared to storage.

Hard Drives

  • Hard Disk Drive (HDD): Contains one or more circular platters that use magnetic particles for data storage.
    • Characteristics include tracks, sectors, platters, and read/write heads.
  • Determining Capacity: Influenced by the number of platters, disk coating, and recording type (longitudinal vs. perpendicular).
  • Formatting: Process of organizing the disk into tracks and sectors.
Head Crash
  • Occurs when a read/write head touches a platter's surface, risking data loss.

Solid-State Drives (SSD)

  • Flash memory storage device with several advantages over HDDs:
    • Faster access and transfer rates
    • Quieter operation and more durability
    • Lighter, lower power consumption, and longer lifespan
    • No need for defragmentation

External Hard Drives and RAID

  • External Hard Drive: Standalone storage device connecting via cables (e.g., USB).
  • RAID: Redundant Array of Independent Disks; allows integration of multiple hard drives to improve data reliability and performance.

Portable Flash Memory Storage

  • Memory Cards: Removable storage for devices (e.g., SDHC, microSD, CF).
  • USB Flash Drives: Store data and connect via USB ports.

Cloud Storage

  • Internet-based service for storing data with remote access.

Optical Discs

  • Types of Optical Discs:
    • CD-ROM: Read-only disc.
    • CD-R: Write-once disc.
    • CD-RW: Rewritable disc.
    • DVD-ROM: High-capacity read-only disc.
    • DVD-R/DVD+R: Write-once competitors.
    • DVD/RW: Rewritable formats.

Enterprise Storage

  • Designed for large organizations for heavy usage and reliability:
    • RAID: Duplicates data for reliability.
    • Network Attached Storage (NAS): Storage dedicated to network users.
    • Storage Area Network (SAN): Centralized storage for connected servers.
    • Tape Storage: Magnetically coated plastic ribbons for large data storage.

Other Types of Storage

  • Magnetic Stripe Cards: Store data on magnetic strips (e.g., credit cards).
  • Smart Cards: Contain integrated circuits for data storage.
  • RFID Tags: Use radio waves for data transmission.
  • NFC Tags: Enable contactless communication for transactions.

Summary

  • Overview of various storage options including capacities, access times, characteristics of hard disks, SSDs, RAID, portable storage, cloud solutions, optical discs, enterprise storage solutions, and types of cards and tags.