Network 101: Understanding Switches and LAN Communication

Wednesday 20 May 2026, 16:00 → 18:50 Africa/Mogadishu

Zoom (Virtual)

Abdiwahid Mohamed Ali (JUST)

Network 101: Understanding Switches and LAN Communication

This webinar introduces the fundamentals of switching technology and explains how devices communicate inside a Local Area Network. Participants will learn how switches use MAC addresses, how traffic is forwarded or flooded, and how to verify basic switch operation using Cisco CLI commands.

The session will also include practical LAN demonstrations, common switching issues, and a brief introduction to advanced switching topics such as VLANs, trunking, STP, EtherChannel, inter-VLAN routing, and port security.

Introduction to Switching Technology

o What is a switch?
o Why switches are used in LANs
o Role of switches in enterprise networks

Convener: Mr Abduwahid Darmad

Network Devices Comparison

o Hub vs Switch vs Router
o Layer 1, Layer 2, and Layer 3 devices
o Where switches operate in the OSI model

Convener: Mr Abduwahid Darmad

Ethernet Basics

o What is Ethernet?
o Ethernet frame overview
o Source MAC address and destination MAC address

Convener: Mr Abduwahid Darmad

MAC Addressing

o What is a MAC address?
o Difference between MAC address and IP address
o How devices use MAC addresses in LAN communication

Convener: Mr Abduwahid Darmad

How Switches Learn MAC Addresses

o MAC address table
o Dynamic learning
o MAC address aging

Convener: Abduwahid Darmad

Switch Forwarding Decisions

o Forwarding
o Flooding
o Filtering
o Unknown unicast traffic
o Broadcast traffic

Convener: Mr ABDULLAHI Darmad

Collision Domains and Broadcast Domains

o Meaning of collision domain
o Hub-based collision problem
o Each switch port as a separate collision domain
o Meaning of broadcast domain
o ARP and DHCP broadcast examples
o Broadcast domain in a default VLAN

Convener: Mr Abduwahid Darmad

Basic Switch Ports and Interfaces, Cisco Switch CLI and Switch Verification Commands

o Access ports
o Uplink ports
o Speed and duplex
o Interface status
• Accessing the switch CLI
• Basic show commands
• Viewing MAC address table
• Checking interface status
• show mac address-table
• show interfaces status
• show running-config
• show vlan brief
• show interfaces fa0/1

Convener: Mr ABDULLAHI Darmad

RECAP AND ASSESSMENT