Arista Networks Cisco Ericsson IPv6 Neighbor Discovery relies on periodic multicast Router Advertisement messages to update timer values and to distribute new information (such as new prefixes) to hosts. On some links the use of periodic multicast messages to all host becomes expensive, and in some cases it results in hosts waking up frequently. Many implementations of RFC 4861 also use multicast for solicited Router Advertisement messages, even though that behavior is optional. This specification provides an optional mechanism for hosts and routers where instead of periodic multicast Router Advertisements the hosts are instructed (by the routers) to use Router Solicitations to request refreshed Router Advertisements. This mechanism is enabled by configuring the router to include a new option in the Router Advertisement in order to allow the network administrator to choose host behavior based on whether periodic multicast are more efficient on their link or not. The routers can also tell whether the hosts are capable of the new behavior through a new flag in the Router Solicitations.