Class 2

Class 2 – Introduction to Cyber Security and Kali Linux

Class Material: Day2

This lecture focuses on the fundamentals of computer networking, the importance of scanning in cybersecurity, and best practices for ethical and safe usage of network tools in Kali Linux.

Key Topics Covered:

1. Basic Network Terminologies

   • A network is a system where devices communicate using IP addresses and transfer data in packets.

   • Devices like routers direct these data packets, much like a post office directs mail.

   • Firewalls serve as security guards, and VPNs act like secure tunnels for safe data travel.

   • The IP address uniquely identifies a device, and data packets carry information across the network.

2. Understanding Scanning and Ports

   • A network scanner detects devices, known as hosts, and identifies the services they run through open ports.

   • Each service (e.g., HTTP, SSH, printer sharing) operates on a specific port.

   • Open ports can be entry points for attackers, which is why port scanning is a crucial skill — and also a potential risk.

3. Safe Cybersecurity Practices

   • Scanning without permission can be illegal or cause damage.

   • Only scan systems you own or have explicit permission to test.

   • Use virtual environments or approved public targets like scanme.nmap.org.

   • Keep firewalls enabled, close unused ports, update tools, and avoid default passwords.

4. Networking & Scanning Tools in Kali Linux

   • Kali Linux includes tools to analyze devices, open ports, and network services.

   • Common tools include ping, traceroute, and nmap, which are used to discover and assess network configurations.

   • These tools must always be used ethically and with permission.

This session emphasizes responsible network scanning, foundational network concepts, and safe tool usage. It introduces students to both the technical and ethical responsibilities of working in cybersecurity, laying the groundwork for more advanced network assessments in the upcoming sessions.