Issue 2: DNS Latency


Several content providers expressed the concern that shim6 will require sifting though the DNS looking for viable ULID/locator pairs.

In reality, shim6 doesn't require this. Rather, client connects to the server just like today.
i.e, the application tries connect to each IPv6 address in turn until one succeeds. Nothing new for shim6 here.
At some (later) point in time, shim6 at either end of the communication determines that some heuristic applies (e.g., number of packets between the pair of IP addresses; NOTE: not per TCP connection). 
That point in time could be *never*