Learn how to protect your Ethernet network from unauthorized access by configuring port security on a Cisco switch! In this free CCNA course segment, we cover: • Why Ethernet ports lack built-in authentication and common attack methods (e.g., Shark Jack, rogue switches, rogue Wi-Fi APs) • Port security basics: MAC-based filtering, default limits, and violation modes (shutdown, restrict, protect) • Step-by-step CLI demo: enabling port security on GigabitEthernet1/0/1, observing learned MACs, and simulating violations with extra devices • Understanding MAC address tables vs. port-security tables, and advanced options (static MAC entries, sticky MAC) • Limitations of dynamic learning and tips for persistent, enterprise-grade security Whether you’re studying for CCNA or hardening your corporate LAN, this tutorial will empower you to prevent unauthorized plugs and unwanted traffic. // Playlist to CCNA Course REFERENCE // // David's SOCIAL // Discord: X: Instagram: LinkedIn: Facebook: TikTok: @davidbombal YouTube: @davidbombal Spotify: SoundCloud: Apple Podcast: // MY STUFF // // SPONSORS // Interested in sponsoring my videos? Reach out to my team here: sponsors@ // MENU // 00:00 – Ethernet Bypass Explained 00:42 – Accessing the Switch via Ethernet Port 03:03 – Unauthorised Devices on the Network 03:35 – CCNA Course Overview with Real Examples 06:48 – How to Enable Port Security 07:56 – Port Security Demo 10:28 – Understanding MAC Addresses 12:55 – Fixing “Err-Disabled” Port State 15:35 – Using ‘shutdown’ and ‘no shutdown’ Commands 15:59 – Testing Port Security in Action 17:47 – Final Thoughts & Key Takeaways Please note that links listed may be affiliate links and provide me with a small percentage/kickback should you use them to purchase any of the items listed or recommended. Thank you for supporting me and this channel! Disclaimer: This video is for educational purposes only. #ccna #networking #security