The technique to prevent this loop is requiring that home routers do not forward traffic before the address acquisition is complete. This will force the home router to treat the IPv6 traffic as unrecognized and transmit ICMPv6 Destination Unreachable message to alert the host to the problem. This behavior will prevent such loops from occurring in the network.

* DHCPv6 IA_PD & IA_NA Interactions. One issue that was uncovered during a previous test event was due to interactions with DHCPv6 Clients and Servers around multiple stateful DHCPv6 options being included in a DHCP message. This issue has not been addressed and was again observed during the April test event. The IETF has started a draft called "Issues with multiple stateful DHCPv6 options," which is aimed at addressing the issues as documented below.

According to RFC 3315, a DHCPv6 server must do the following: "If the server will not assign any addresses to any IAs in a subsequent Request from the client, the server MUST send an Advertise message to the client that includes only a Status Code option with code NoAddrsAvail and a status message for the user, a Server Identifier option with the server's DUID, and a Client Identifier option with the client's DUID."

Also, a client must react according to the following text from RFC 3315: "The client MUST ignore any Advertise message that includes a Status Code option containing the value NoAddrsAvail, with the exception that the client MAY display the associated status message to the user."

The IETF issued errata in August 2010 that change the behavior described in RFC 3315. The RFC has been updated to state the following for a DHCPv6 server: "If the server will not assign any addresses to an IA in a subsequent Request from the client, the server MUST send an Advertise message to the client that includes the IA containing a Status Code option with status code NoAddrsAvail and a status message for the user, a Server Identifier option with the server's DUID, and a Client Identifier option with the client's DUID. The server SHOULD include other stateful IA options (like IA_PD) and other configuration options in the Advertise message."