It would seem to me that while due to the fact we are tunneling most everything we may have a logical full mesh but far from a physical full mesh. What does a tunneled logical full mesh really accomplish for us other than making things all the more complicated? Wouldn't traditional peering and routing done "the normal way" be much easier? I can see a valid place for nailing up vpn links and various tunnels, i.e. last mile access and tying islands together though something other than IPIP with links negotiated on a peering basis as needed, but what does a full logical mesh of tunnels give us? It seems that since it's built of tunnels and thus virtual rather than physical we just unnecessarily complicate the mess wherein the tunneled traffic and the tunnels themselves end up taking multiple and somewhat changing hops to get from one end to another. IP was designed such that I could hand a packet off and basically go, "ok, now it's your problem to deliver it (on a best effort basis)", thus I shouldn't need to know every conceivable route to every conceivable endpoint. What prevents us from using it that way?
Eric AF6EP