est of the IP configuration. The UE also configures the IPv6 link-local address based on the IID received from the PGW. 8. At this point, the IP connectivity, that is, the PDN Connection and the default EPS Bearer, has been set up for a dual-stack. The PDN Connection appears to the UE IP stack as a dual-stack enabled network interface. The actual 'type' of the interface can be PPP, Ethernet, or something else based on the UE side implementation. The UE joins the all-nodes multicast address multicast group. The UE may join the solicited-node multicast address multicast group for all the present and future configured addresses on its interface (which would imply sending the required Multicast Listener Discovery (MLD) messages). The UE does not need to do a DAD for its link-local address since the address collision is not possible by design (assuming that the UE follows the 3GPP specifications). 9. Once the IP connection (i.e. the PDN Connection) is up, the SLAAC takes place and the UE may solicit the router by sending a Router Solicitation. The PGW sends one or more IPv6 Router Advertisement to the UE. The Router Advertisement carries at minimum the PIO option containing the /64 IPv6 prefix assigned by the network to the UE and the PDN Connection. The lifetimes of the IPv6 prefix have been set to infinite, the 'A'-flag is set to one, and the 'L'-flag is set to zero. The router lifetime setting depends of the PGW configuration but is typically close to the maximum possible value. The 'M' bit is set to zero and the 'O' bit may be set to zero or one. Other possible options in the Router Advertisement may, for example, include the MTU option. After receiving the Router Advertisement, the UE completes the SLAAC and configures a GUA for its interface. The IID of the configured GUA may be anything that the UE thinks is appropriate, for example, using privacy addresses [109]. The UE does not need to do a DAD for its GUAs since address collision is not possible by Deploying IPv6 in 3GPP Networks design (assuming that the UE