-We shall use `fe80::/64` addresses to indicate the remote end point, with
-the following additional information:
-
- * **TODO:** how; specifically, IPv6 addresses don't fit in here!
-
-Kademlia uses a number of messages:
+The link-local addresses used to convey Kademlia peers are not the usual
+`fe80::/64` addresses, but they are 6bed4 address. Depending on the
+[prefix and its promises](PREFIXES.MD), there may be a globally routable
+IPv6 address or not; there may or may not be an IPv4 address in the top
+half address. In any case, the lower half of the address can be interpreted
+for 6bed4 peering, so this will lead to an IPv4 address and an UDP port.
+It is not important if this lower half information points to an end user
+or a Kademlia node; as long as it is usable for routing purposes.
+
+This is perhaps the vital part of peer-to-peer routing, the ability of
+end users to perform routing. To this end, they should be clear about
+their reachability, which usually hinges on either local port forwarding
+or a fallback server that is reachable under an IPv4 address.
+
+Note how the routability of an IPv6 prefix is not dependent on the
+actual presence of a native IPv6 route to the Kademlia node; we created
+6bed4 precisely to overcome that obstacle. And `fc64::/16` is also
+usable for the same purposes, as this clearly defines a local network
+to be used. When a routable IPv6 prefix is provided, especially when it
+is a native one, then connectivity over IPv6 is also arranged, which
+is desirable as an alternative to IPv4-based routing (using 6bed4).
+
+At some point in the future, we may not be able to rely on IPv4 as a
+routing layer; by then, the address 0.0.0.0 will be used in the lower
+half of the address to indicate that situation.
+
+Kademlia uses a limited number of
+[protocol messages](https://en.wikipedia.org/wiki/Kademlia#Protocol_messages):