TryHackMe LAN Topologies and Networking Concepts

Introduction

• Presenter: John
• Topic: Introduction to LAN (Local Area Network) topologies and basic networking concepts.

LAN Topologies

• Topology Definition: Design or layout of a network.

Star Topology

• Description: Devices are connected to a central networking device (switch/hub).
• Advantages:
  • Reliability and scalability.
  • Easy to add more devices.
• Disadvantages:
  • Costly due to more cabling and equipment.
  • Increased maintenance and troubleshooting complexity.
  • Single point of failure if central device fails.

Bus Topology

• Description: Devices are connected to a single backbone cable.
• Advantages:
  • Cost-effective and easy to set up.
• Disadvantages:
  • Prone to slowdowns and bottlenecks.
  • Difficult troubleshooting.
  • Single point of failure if backbone cable breaks.

Ring Topology

• Description: Devices are connected in a loop or ring.
• Advantages:
  • Less cabling required.
  • Easy to troubleshoot faults due to sequential connection.
• Disadvantages:
  • Inefficient data travel due to single-direction flow.
  • Entire network fails if cable breaks.

Networking Devices

Routers

• Function: Connect networks and route data between them.
• Use Case: Translates and directs data across different networks (e.g., internet connections between homes).

Switches

• Function: Aggregates multiple devices within a network using Ethernet.
• Features:
  • Connects various devices using ports (4, 8, 16, etc.).
  • Uses packet switching to efficiently transmit data.
  • Doesn't perform routing.

Subnetting

• Definition: Dividing a network into smaller sections (subnets).
• Purpose: Improves efficiency, security, and control of networks.
• Uses: Splits networks into departments or use cases (e.g., public vs. employee networks).
• Subnet Mask: A 32-bit number representing network size.

Key Terms

• Network Address: Identifies the start of a network.
• Host Address: Identifies a device within a network.
• Default Gateway: Device for sending data outside the network.

Protocols

ARP (Address Resolution Protocol)

• Purpose: Associates MAC addresses with IP addresses.
• Functionality: Sends ARP requests to find device MAC addresses, stores mappings in ARP cache.

DHCP (Dynamic Host Configuration Protocol)

• Function: Automatically assigns IP addresses to devices on a network.
• Process:
  • Device sends a DHCP Discover request.
  • Server offers an IP address.
  • Device requests offered address.
  • Server acknowledges assignment.

Additional Learning

• Recommended to study the OSI Model for further understanding of network protocols and layers.

These notes cover the key points of the TryHackMe session on LAN topologies and basic networking concepts. They provide an overview of different network designs, how routers and switches function, and how subnetting and protocols like ARP and DHCP facilitate network communication. For further details, refer to practical examples or interactive tasks in TryHackMe.