[rrg] Fundamental objections to a host-based scalable routing solution

[Christian Vogt]

Dino Farinacci wrote:

> The hosts do not have visibility of the path. They only know the other
> end is sending them packets. And you get this as well from a
> router-based approach.

Dino,

in both host-based and network based solutions, the availability status
of a path needs to be measured through the delivery, or the lack of
delivery, of packets.  My point is that the faithfulness of such
measurements differs between host-based and network-based solutions:

For host-based solutions, delivery of a packet is reliable evidence
that a path is available because the packet has traveled the entire
end-to-end path.  For network-based solutions, delivery of a packet is
less reliable evidence, because it doesn't account for path failures
downstream of the router receiving the packet.

- Christian