What is the primary purpose of Duplicate Address Detection (DAD)?

The primary purpose of Duplicate Address Detection (DAD) is to ensure no other devices are using the same IPv6 address. This mechanism is a crucial part of the IPv6 address allocation process. When a device wants to use a specific IPv6 address, it sends out a Neighbor Solicitation message to check if that address is already in use by any other device on the local link. If no other device responds, it confirms the address is unique, allowing the device to configure itself with that address. This process is important because it prevents address conflicts, which can lead to communication issues within the network.

In contrast, the other options relate to different aspects of network management and address configuration. For example, configuring static addresses is not the primary function of DAD, and neither is identifying rogue devices or managing address changes in DHCP, which are handled by different protocols and methodologies. Thus, the focus of DAD remains solely on ensuring the uniqueness of IPv6 addresses to maintain reliable network communication.