part 2

unit 4 analysis

1. Von Neumann Cycle (Fetch-Decode-Execute Cycle) The Von Neumann architecture follows a structured sequence of steps to i process instructions: 1. Fetch: The CPU retrieves an instruction from memory. 2. Decode: The instruction is interpreted. 3. Execute: The CPU carries out the instruction. Components of the CPU involved in the Cycle: • Memory Address Register (MAR): Holds the address of the instruction/data being accessed. • Memory Data Register (MDR): Holds the actual instruction or data fetched. • Control Unit (CU): Manages data flow and execution of instructions. • Program Counter (PC): Keeps track of the address of the next instruction. • Registers: Small memory units inside the CPU that store temporary data. 2. CPU Performance Factors The CPU’s efficiency depends on multiple factors: • Clock Speed: Measured in Hertz (Hz), higher clock speeds allow more instructions to be processed per second. • Number of Cores: More cores enable simultaneous execution of multiple tasks (parallel processing). • Cache Memory: Stores frequently used data for quick access, reducing delays from fetching data from RAM. • Bus Width: Determines how much data can be transferred at once, impacting system speed. 3. Memory & Storage Types Primary Memory (Volatile) • RAM (Random Access Memory): Stores active programs and data; erased when power is lost. • Cache Memory: Built into the CPU for faster access than RAM. • Registers: Even faster, used for immediate data processing. Secondary Memory (Non-Volatile) • Hard Disk Drive (HDD): Uses magnetic storage, slower but cheaper. • Solid-State Drive (SSD): Faster than HDDs, uses flash memory. • Optical Discs (CD/DVD): Used for media and data backup. Virtual Memory • When RAM is full, part of the hard drive is used as “extra” memory. • Slower than real RAM but prevents system crashes. Read-Only Memory (ROM) • Stores permanent data, such as firmware and system boot instructions. 4. Input & Output Devices Input Devices (Used to Enter Data) • Keyboard, Mouse, Touchscreen • Microphone (For Voice Input) • Scanners & Sensors (For Digital Conversion) Output Devices (Display or Provide Results) • Monitor (Visual Output) • Speakers (Audio Output) • Printers (Physical Document Output) Storage Devices (For Data Retention) • USB Flash Drives, External Hard Drives • Cloud Storage (Online Storage Solutions) 5. Operating Systems (OS) The OS is responsible for managing hardware and software resources: • Functions of an OS: • Memory Management: Allocates RAM efficiently. • Process Management: Manages running programs. • File System Management: Organizes storage. • Security & User Management: Provides user authentication. • Examples of OS: • Windows, macOS, Linux (For PCs) • Android, iOS (For Mobile Devices) 6. Networking & Internet Concepts Types of Networks • LAN (Local Area Network): Covers small areas like homes or offices. • WAN (Wide Area Network): Covers large areas, including the internet. • Wired Networks: Use cables (Ethernet) for fast, stable connections. • Wireless Networks: Use Wi-Fi, Bluetooth, or mobile networks. Networking Concepts • IP Address: Unique identifier for devices on a network. • MAC Address: Hardware address of a device. • Protocols: Rules for communication (e.g., TCP/IP for the internet). 7. Cybersecurity & Threats Types of Cyber Threats • Malware (Viruses, Trojans, Ransomware): Harmful software that damages or steals data. • Phishing: Fake emails or messages tricking users into giving personal data. • Hacking & Unauthorized Access: Breaches in system security. Preventative Measures • Firewalls: Block unauthorized access. • Antivirus Software: Detects and removes malware. • Encryption: Converts data into unreadable format for security. • Multi-Factor Authentication (MFA): Adds extra layers of security beyond passwords. Final Thoughts This document covers essential topics related to computer architecture, hardware, memory, networking, and securit

unit 3 part