Abstract: A system and method for intelligently detecting a duplicate address attack is described. The system and method comprise transferring a first address conflict check message; receiving a first address conflict check response message; performing intelligent Duplicate Address Detection (DAD) to determine if the duplicate address attack is valid; and if the duplicate address attack is valid, then reporting the duplicate address attack to a monitoring server. An intelligent switch that detects the DAD attack blocks further address conflict check response messages from the attacker's MAC address.