問題文
A team runs OSPFv3 for IPv6 unicast and wants the same deployment to carry IPv4 unicast prefixes over the same links rather than adding a second OSPFv2 deployment beside it. They configure the extra address family, which the software maps onto a realm. What does that mapping mean for the way the deployment runs?
選択肢
- Both families are carried in one link-state database and by one set of neighbors, and the instance identifier that is added merely tells the far end which of the two families any prefix belongs to.
- Each realm holds a set of neighbors and a link-state database of its own, and each one is configured on its own with an area and at least one interface.
- The realms share their neighbors but not their databases, so an adjacency that comes up for one family brings every other family up with it.
- The IPv4 prefixes ride inside the advertisements of the IPv6 family as one more kind of prefix, so only the border device needs the extra family.