When searching for all devices using their MAC address, some IPv6 devices do not show up. Why?
Some IPv6 devices do not appear following a search for all devices using the MAC address option because devices such as the Vista IPv6 computer do not report their MAC address in the Solicit message. As a result, they are known only by their DUID. If a device reports its MAC address in the CableLabs Device ID option, then you can locate that device using its DUID or its MAC address.