Class 3
Class 3 – Networking & Security Fundamentals
Class Material: Week 2
This lecture focuses on the fundamentals of networking, layered communication models, IP addressing, network configurations, and foundational elements needed to understand how devices communicate securely and efficiently in a networked environment.
Key Topics Covered:
OSI and TCP/IP Models
The OSI model breaks down network communication into seven layers, while the TCP/IP model is a simplified, practical version used in real networks.
Each layer has specific functions, such as application, transport, and network communication handling.
Network Topologies
Describes the physical and logical layout of networks, such as star, mesh, and ring topologies.
Each topology has benefits and drawbacks depending on use case and scale.
IP Addressing
Explains the difference between public and private IPs, IPv4 and IPv6, and the concept of subnetting.
Subnet masks help define network boundaries, while gateways serve as the exit point from a local network.
MAC Addressing
Covers the role of MAC (Media Access Control) addresses and how they uniquely identify hardware devices on a network.
Also explains how Organizationally Unique Identifiers (OUI) relate to MACs.
Network Address Translation (NAT)
NAT allows private IP addresses to communicate with the internet using a single public IP.
This improves IP efficiency and adds a layer of security by masking internal IP addresses.
Ports and Protocols
Introduces the concept of TCP and UDP ports used by various services (e.g., HTTP, SSH).
Helps understand how firewalls manage access to these ports for security.
DNS and DHCP
Covers how DNS resolves domain names to IP addresses and DHCP assigns dynamic IPs to devices.
These services are essential for internet communication and automated IP management.
This lecture builds the networking foundation needed to understand more advanced cybersecurity practices. Learn how systems identify, communicate, and secure connections through structured models and standardized protocols.