Comp (7?)

Week 6: Secondary Storage

Introduction

  • Data Storage Evolution: Transition from basic text and numeric files to complex digital formats including:

    • Digital music files

    • Photographic files

    • Video files

    • Requirement for greater storage capacity due to new file types.

Learning Objectives

  1. Distinguish between primary and secondary storage.

  2. Identify important characteristics of secondary storage including:

    • Media

    • Capacity

    • Storage devices

    • Access speed

  3. Define solid-state storage covering:

    • Solid-state drives (SSDs)

    • Flash memory cards

    • USB drives

  4. Describe components of hard disks such as:

    • Platters

    • Tracks

    • Sectors

    • Cylinders

  5. Compare performance enhancements in storage technology:

    • Disk caching

    • RAID

    • Hybrid drives

    • File compression and decompression

  6. Define optical storage including:

    • Compact discs (CDs)

    • Digital versatile discs (DVDs)

    • Blu-ray discs

  7. Compare different types of drives:

    • Internal drives

    • External drives

    • Network drives

  8. Define cloud storage and associated services.

  9. Describe mass storage solutions:

    • Mass storage devices

    • Enterprise storage systems

    • Storage area networks (SANs)

Primary vs. Secondary Storage

  • Primary Storage:

    • Volatile storage: Loses content when power is lost.

    • Temporary storage: e.g., Random Access Memory (RAM).

  • Secondary Storage:

    • Nonvolatile storage: Retains data without power.

    • Permanent storage: Saves information for future use.

Characteristics of Secondary Storage

  • Media: Specifies the physical material that holds data and programs.

  • Capacity: Measures total data storage capability of the medium.

  • Storage Devices: Hardware that retrieves data and programs from storage media.

  • Access Speed: Indicates the time taken to retrieve data from storage.

Solid-State Storage

  • Types of solid-state storage include:

    • Solid State Drives (SSDs): Use flash memory technology for storing data.

    • Flash Memory Cards: Typically used in cameras and smartphones.

    • USB Drives: Portable storage devices utilizing flash memory.

Hard Disks

  • Functionality: Save files by altering magnetic charges on the disk's surface to represent binary data (1s and 0s).

    • Physical Structure: Comprises rigid metallic platters stacked vertically.

    • File Organization: Utilizes tracks, sectors, and cylinders to manage data.

Types of Hard Disks

  1. Internal Hard Drive: Built into the computer.

  2. External Hard Drive: Connects to the computer via USB or other ports.

  3. Network Drive: Accessible over a network; often used in shared environments.

Performance Enhancement Techniques

  • Disk Caching: Predicted data need is stored temporarily for quicker access.

  • Hybrid Drives: Combines SSD and traditional hard disk technologies.

  • RAID (Redundant Array of Independent Disks): Links multiple hard drives for redundancy or performance improvement.

  • File Compression: Reduces file size for efficient storage.

  • File Decompression: Restores compressed files to their original size.

Optical Disks

  • Data Representation: Uses reflective light to represent data using lands and pits; lands signify binary ones, while pits signify zeros.

  • File Organization: Organizes files in tracks, but typically utilizes a single track unlike hard disks.

Capacities and Types of Optical Disks

  • Compact Disc (CD): Capacity of 700 MB; traditionally used for audio.

  • Digital Versatile Disc (DVD): Capacity of 4.7 GB; widely used for video storage.

  • Blu-ray Disc (BD): Capacity usually 50 GB, with hi-definition video storage capabilities.

  • Ultra HD Blu-ray (UHD BD): Holds up to 100 GB, supporting 4K video.

Types of Optical Disks Explained

  • ROM (Read Only Memory): Data cannot be written or erased.

  • R (Recordable): Data can be written once.

  • RW or RAM (Rewritable/Random Access Memory): Data can be written and erased multiple times.

Cloud Storage

  • Definition: Utilizes internet-based servers to store data.

    • Service Model: Applications provided as services, rather than products.

    • Providers: Examples include:

    • Google Drive

    • Dropbox

    • Microsoft OneDrive

    • Amazon Drive

    • Apple iCloud

Cloud Storage Advantages and Disadvantages

  • Service advantages include ease of file access and sharing.

  • Potential disadvantages may cover security and dependency on internet connectivity.

Mass Storage Devices

  • Purpose: Meets organizational needs for high-capacity secondary storage.

  • Enterprise Storage Systems: Facilitates safe data use and management across networks.

  • Types of Devices:

    • File servers

    • RAID systems

    • Network Attached Storage (NAS)

Storage Area Network (SAN)

  • Definition: Architecture connecting remote storage devices.

    • User's computer handles the file system, while SAN provides dedicated disk space.

    • Enables remote data storage while allowing secure and efficient access.

Careers in IT

  • Disaster Recovery Specialists: Focused on recovering systems/data post-disaster.

  • General Requirements:

    • Bachelor's or associate's degree in Computer Science or Information Systems.

    • Experience in networking, security, and database administration.

    • Strong communication and stress management skills.

  • Salary Range: $63,000 to $112,000 annually.

Future of Storage

  • Next Generation Storage Innovations: Exploring futuristic storage options utilizing:

    • Heat

    • Lasers

    • DNA

  • Ongoing efforts by manufacturers to increase storage capacity without enlarging physical dimensions of storage devices.