In a switch spoofing attack, the network attacker configures a system to spoof itself as a switch. Typically, this is achieved by connecting an unauthorized Cisco switch to the switch port. The authorized switch can send DTP frames and form a trunk. The attacker again has access to all the VLANs through the trunk. In Figure 6-8, an unauthorized switch can form a trunk with the Cisco switch. The attacker device connects to the unauthorized switch and can attack a victim in another VLAN.