Although the IPv6 address space within a single /64 subnet is very
large, the typical distribution of the addresses in this space is
very non-uniform. This non-uniformity, together with the dictionary-
based DNS brute-force enumeration, allows practical remote mapping of
the IPv6 addresses in these subnets. This document proposes a
technique which can be used to decrease the exposure of the server
subnets to trivial scanning. As a side effect, the proposed
technique allows to drastically simplify the address management.