The Internet and Its uses CURR

The Internet and World Wide Web (WWW)

Internet

  • Definition: "internet" derives from "INTERconnected NETwork" and represents a global collection of interconnected computer networks.

  • Infrastructure: Relies on physical infrastructure for connectivity between networks and individual devices.

World Wide Web (WWW)

  • Definition: A subset of the internet, the World Wide Web consists of a vast collection of multimedia web pages and is accessible via web browsers.

  • Technology: Based on Hypertext Transfer Protocol (HTTP).

Differences Between Internet and WWW

Internet

  • A worldwide network of interconnected computers.

  • Utilizes Transmission Control Protocol (TCP) and Internet Protocol (IP) for data transmission.

  • Supports email communications and online chatting (text, audio, video).

WWW

  • A compilation of multimedia web pages and other resources accessible through browsers.

  • Uses HTTP(S) and HTML for formatting.

  • URLs serve as addresses for locating web pages.

Uniform Resource Locators (URL)

  • Definition: Text addresses that identify the location of files on the internet, such as websites and images.

  • Structure:

    • Protocol: Typically HTTP or HTTPS.

    • Website Address: Comprises domain host, domain name, and domain type (e.g., .com, .org).

    • Path: Represents the specific page, often omitted.

    • File Name: Represents the specific resource (e.g., image or page).

HTTP and HTTPS

  • HTTP: A protocol governing file transfer across the web.

  • HTTPS: An extension of HTTP that incorporates encryption for secure data transmission.

  • Importance of SSL: Secures the connection and encrypts data sent between the client and server.

Domain Name System (DNS)

  • Function: Resolves URLs to IP addresses enabling browsers to locate web servers.

  • Operation:

    1. User types a URL in a browser.

    2. The browser queries a DNS server for the corresponding IP address.

    3. If unresolved, a request is sent to other DNS servers until resolved.

    4. The IP address is cached for future use and used to access web content.

    5. . The computer now sets up a communication with the website server and the required pages are downloaded.

Web Browsers

  • Definition: Software that enables users to access and view web pages.

  • Examples: Mozilla Firefox, Safari, Edge, Google Chrome.

  • Key Features:

    • Homepage and bookmark capabilities.

    • History tracking of visited websites.

    • Multi-tab browsing.

    • Navigation through hyperlinks.

Cookies

Cookies: Small files saved on a user's computer that track internet usage, browsing activity, IP address, and remember user preferences.

  • Types:

    • Session Cookies: Temporary and deleted after the browser is closed.

    • Persistent Cookies: Remain on the computer until a set expiry date.

  • Purpose: Enhance user experience by remembering login details and preferences.

Digital Currency and Cryptocurrency

  • Digital Currency: This exists only in digital form and is used for online transactions (e.g., PayPal, Apple Pay).

  • Cryptocurrency: A decentralized form of digital currency using cryptography for secure transactions, typically tracked on blockchain technology.

Blockchain

  • Definition: A decentralized database that stores transaction records in a secure and tamper-resistant manner.

  • How it Works: New transactions create a block with a unique hash value that links to the previous block; attempts to alter it invalidate subsequent blocks.

Cybersecurity Threats

  • Common threats include brute force attacks, data interception, hacking, malware, and social engineering.

  • Preventive Measures:

    • Use of firewalls, malware checkers, strong password policies, and regular software updates.

Security Protocols

  • SSL and HTTPS: Ensure secure communications over the internet by encrypting data exchanged between servers and clients.

  • Firewalls and Proxy Servers: Act as barriers to protect networks from unauthorized access and manage traffic.

Authentication and Access Control

  • Authentication Methods:

    • Something you know (passwords).

    • Something you have (mobile devices).

    • Biometric verification (fingerprints, facial recognition).

  • Access Levels: Determine permissions for users based on their roles (e.g., teacher vs. student).

Malware Types

  • Viruses: Self-replicating programs that damage system files.

  • Worms: Stand-alone malware that spreads across networks.

  • Trojan Horses: Disguised malicious software that harms the computer system once executed.

  • Spyware: Monitors user activities and collects personal data.

  • Adware: Generates unwanted advertisements on the user’s device.

  • Ransomware: Restricts access to the system until a ransom is paid.

Preventive Strategies Against Cyber Threats

  • Regularly update software, use strong and varied passwords, enable encryption, conduct security training, and utilize reputable security software.

EXTRA:

DDoS Attack: Overwhelms a targeted server or network with traffic from multiple devices, causing service disruptions.

Brute Force Attack: Attempts to gain unauthorized access by trying all password combinations until the correct one is found.

Data Interception: Unauthorized capture of data in transit, allowing attackers to access sensitive information through methods like packet sniffing or man-in-the-middle attacks.

  • Hacking: Unauthorized access to computer systems or networks to steal, modify, or delete data. Includes ethical hacking (testing security) and malicious hacking (exploiting vulnerabilities).

  • Malware: Malicious software designed to harm or exploit devices and networks, including viruses, worms, ransomware, spyware, and adware.

  • Phishing: A fraudulent attempt to obtain sensitive information (like usernames, and passwords) by disguising as a trustworthy entity in electronic communications, often through emails or messages that appear legitimate.

  • Pharming: A cyber attack intended to redirect users from legitimate websites to fraudulent ones without their knowledge, manipulating DNS settings or exploiting vulnerabilities to redirect traffic.

  • Social Engineering: Psychological manipulation to trick individuals into divulging confidential information, using techniques such as phishing, pretexting, bait

Cybersecurity Threats Overview

Emails/Phishing Scams

  • Definition: Fraudulent emails designed to trick recipients into providing sensitive information, posing as a legitimate source.

Scareware

  • Definition: Malicious software that uses fear tactics to lure users into purchasing potentially harmful software through false alerts.

Instant Messaging

  • Definition: Cyber threats that exploit messaging platforms to deliver malicious links or scams directly to users.

Baiting

  • Definition: A tactic that entices users with the promise of free items or services to manipulate them into compromising their security.

Phone Calls

  • Definition: Scams where attackers impersonate trustworthy entities over the phone to extract confidential information from victims.