14.9.11 Packet Tracer - Layer 2 Vlan Security Site

On the access ports connecting to end devices (Fa0/1, Fa0/2, etc.), you need to lock down the MAC addresses.

interface g0/1 switchport mode trunk switchport nonegotiate If a port is for a user, it should be an access port, period. Don't let devices negotiate their way into privilege. Step 3: Changing the Native VLAN (Double Tagging Defense) The Threat: In a double-tagging attack, the attacker sends a frame with two 802.1Q tags. The first tag (native VLAN) is stripped off by the first switch. The second tag (say, VLAN 10) is then visible to the next switch, potentially letting the attacker hop into a restricted VLAN. 14.9.11 packet tracer - layer 2 vlan security

Take the time to run this lab. Break it on purpose. Watch the show port-security , show dhcp snooping binding , and show interfaces status err-disabled outputs. On the access ports connecting to end devices

Cisco’s Packet Tracer activity is an excellent, hands-on lab that forces you to think like both a network admin and a hacker. It focuses on three critical Layer 2 vulnerabilities and their mitigations: MAC Flooding , VLAN Hopping (Switch Spoofing) , and DHCP Starvation . Step 3: Changing the Native VLAN (Double Tagging

By default, switches are trusting. And trust, in security, is a vulnerability.

Layer 2 security is invisible when done right. But when it's missing, the whole network crumbles. What other Layer 2 attacks worry you most—CDP/LLDP recon, STP manipulation, or ARP poisoning? Drop a comment below.