There are two methods of advertising RIPng default routes. You can configure a router to advertise RIPng default routes according to the actual networking. Additionally, you can specify the cost of the default routes to be advertised.
By configuring a RIPng router to advertise the summarized IPv6 address on an interface, you can save the space used by RIPng routes in the routing table. You can also set parameters to prevent an interface from learning the same summarized route.