Module 7: Digital Storage: Preserving Your Content
Module Objectives
Differentiate between storage and memory: Understanding the specific roles each plays in computing.
Identify storage hardware types: Recognizing the physical devices used for data retention.
Discuss cloud computing concepts: Learning the architecture of internet-based services.
Evaluate cloud storage options: Comparing different providers and service models.
Explain how to secure your cloud data: Implementing strategies to protect information online.
Identify enterprise and other storage options: Exploring large-scale and specialized storage solutions.
Explain how memory relates to storage: Understanding the interaction between temporary and permanent data locations.
Identify risks for the Internet of Things (IoT): Assessing privacy and security implications of connected devices.
Storage and Memory Concepts
Combined Usage: Computers and devices utilize both storage and memory to access, process, and save data.
Memory Definition: Memory consists of electronic components that store: * Instructions waiting for execution by the processor. * Data required by those specific instructions. * The processed results (information).
Storage Definition: Refers to long-term, permanent access to data and information. It is compared to a file cabinet for digital content.
Volatility vs. Nonvolatility: * Memory (RAM): Specifically volatile, meaning it holds data and instructions only temporarily while power is supplied. * Storage Medium: Specifically nonvolatile, meaning it retains its content when power is removed. It is also known as secondary storage.
Storage Medium Examples: Locations where a computer keeps data, programs, and applications, including: * Digital storage (cloud). * Hard disks. * Solid-state drives (internal or external). * Memory cards. * USB flash drives. * Optical discs. * Tags.
Cloud Storage: Keeps information on remote servers accessible via the Internet.
Storage Process Definitions: * Storage Device: The hardware that records (writes) and/or retrieves (reads) items to and from storage media. * Writing: The process of transferring data, instructions, and information from memory to a storage medium. * Reading: The process of transferring items from a storage medium into memory.
Defining Storage Capacity and Speed
Capacity: The number of bytes (characters) a storage medium can hold.
Standard Storage Terms: * Kilobyte (KB): Approximately $1\,thousand$ bytes. * Megabyte (MB): Approximately $1\,million$ bytes. * Gigabyte (GB): Approximately $1\,billion$ bytes (). * Terabyte (TB): Approximately $1\,trillion$ bytes (). * Petabyte (PB): Approximately $1\,quadrillion$ bytes. * Exabyte (EB): Approximately $1\,quintillion$ bytes. * Zettabyte (ZB): Approximately $1\,sextillion$ bytes. * Yottabyte (YB): Approximately $1\,septillion$ bytes.
Access Time: Defines the speed of storage and memory through two measurements: 1. The time required for a storage device to locate an item on the medium. 2. The time required to deliver an item from memory to the processor.
Transfer Rate: The speed at which data, instructions, and information move to and from a device, stated in: * * *
Hard Drives and Magnetic Storage
Internal Hard Drive: The most common storage medium. The term "hard drive" collectively refers to hard disks and SSDs. Local files on an internal hard drive cannot be accessed on other devices directly.
Magnetic Hard Disk Drive (HDD): * Contains one or more inflexible, circular platters. * Uses magnetic particles to store data. * Generally offers greater capacity at a lower cost than solid-state equivalents.
HDD Capacity Determiners: * Number of platters. * Composition of the magnetic coating. * Recording method (longitudinal or perpendicular). * Density (the number of bits in a specific area; higher density equals higher capacity).
Magnetic Recording Methods: * Longitudinal Recording: Aligns magnetic particles horizontally around the surface. * Perpendicular Recording: Aligns magnetic particles vertically, perpendicular to the surface.
Storage Anatomy and Formatting: * Platter: Made of aluminum, glass, or ceramic with a thin alloy coating. * Formatting: The process of dividing the disk into tracks and sectors. * Track: A narrow recording band forming a full concentric circle on the platter surface. * Sector: Wedge-shaped sections that break tracks into arcs. A sector is the individual block of data. * Cluster: A grouping of several sectors.
Mechanical Operation: * Read/Write Head: Mechanism that reads and writes items. Each platter side has its own head. * Head Actuator: Connects to arms that move the read/write heads to the correct platter location.
External Hard Drives: Separate, free-standing storage in an airtight, sealed case that connects via USB or other ports.
Flash Memory and Optical Storage
SSD (Solid-State Drive): * A flash memory storage device. * Flash Memory: Nonvolatile memory that can be erased and rewritten electronically. * Solid-state Media: Consists entirely of electronic components with no moving parts.
Portable Flash Memory: * Memory Card: Removable device often used with cameras to transport photos, music, and video. * USB Flash Drive: Removable storage that plugs into a USB port for easy file transport.
Optical Media: Storage consisting of a flat, round portable disc (metal, plastic, lacquer) read/written by a laser. Usage is currently declining. * CD (Compact Disc): CD-ROM (read-only), CD-R (recordable), CD-RW (rewritable). Typically used for audio/photos. * DVD (Digital Versatile Disc): DVD-ROM (read-only), DVD-R/DVD+R (recordable), DVD-RW/DVD+RW/DVD+RAM (rewritable). Typically used for video. * Blu-ray (BD): A higher-capacity disc than DVD, used for high-definition video.
Cloud Computing and Storage Services
Cloud Infrastructure: * Front End: Hardware and software a user interacts with to access the cloud. * Back End: Servers and storage devices managing and storing resources.
Benefits: Accessibility, cost savings, space savings, and scalability.
Business Model: Allows companies to outsource IT infrastructure to third-party providers.
Cloud Service Categories: * SaaS: Software as a Service. * IaaS: Infrastructure as a Service. * STaaS: Storage as a Service. * DaaS: Data as a Service. * PaaS: Platform as a Service. * Other Services: Desktop as a service, file synchronization, document writing, file backup, and media streaming.
Cloud Storage Options: * Integrated Apps: Google Drive and Microsoft OneDrive provide cloud-based apps for creation and editing. * Pure Storage: Box serves primarily as a storage location without corresponding productivity apps. * Flexibility: Users do not need to purchase or maintain their own servers.
Security and Digital Payments
Cloud Security Steps: * Verify the reputation and longevity of the provider. * Ensure the provider uses encryption. * Check compatibility with devices. * Review user agreements and set advanced privacy settings. * Use strong passwords and two-factor authentication (2FA).
Digital Financial Tools: * Cryptocurrency: Digital currency for transfers, not backed by a government. * Payment Apps: Examples include Venmo, which transfers money between bank accounts/credit cards. * Digital Wallet: Apps like ApplePay connected to financial accounts for payments.
Enterprise Storage Solutions
Characteristics: Intended for heavy use, maximum efficiency, and high availability (, ).
Redundancy: Having multiple components so that if one fails, another assumes its tasks.
Data Centers: Secure locations with many large computers acting as servers.
RAID (Redundant Array of Independent Disks): A group of two or more integrated hard drives used to improve reliability and performance. * Level 1 (Mirroring): Writes data on two drives simultaneously to duplicate data for reliability. * Striping: Splits data across multiple drives to improve access times.
Network Storage Architectures: * Network Attached Storage (NAS): A storage appliance/server with its own IP address on a network dedicated to providing storage. * Storage Area Network (SAN): A high-speed network of only storage devices, often using fiber-optic cables to connect servers to large storage capacities.
Specialized Storage and IoT
Additional Storage Types: * Tape: Magnetically coated plastic ribbon; low cost for large data volumes. * Magnetic Stripe Card: Contains a stripe with identifying info (e.g., credit cards). * Smart Card (Chip Card): Stores data on an integrated circuit; exists in contact and contactless versions. * RFID (Radio Frequency Identification): Consists of an antenna and a memory chip. Tags are either active or passive and are read by radio waves. * NFC (Near Field Communication): Based on RFID; uses close-range radio signals ( devices and self-adhesive tags).
Memory/Storage Relationship: * Operating System: Managed via memory chips on the motherboard. * Addresses: Unique numbers identifying the location of a byte in memory. The computer references these to access data. * CMOS (Complementary Metal-Oxide Semiconductor): Technology used for RAM and flash memory; provides high speeds, consumes little power, and uses battery power to retain info (like startup settings) when the device is off.
Internet of Things (IoT) Ethics: * Examples: Smart electric meters, wearable tech, vehicle black boxes, smart thermostats, and medicine bottles with wireless chips. * Privacy Concerns: Technology experts argue the security, health, and productivity benefits outweigh the potential privacy risks, though companies must ensure data confidentiality.