On Sun, 2007-09-30 at 11:40 +0930, Mark Smith wrote:
The model we're talking about seems to me to be that old model on it's head. The devices at the edge of the core network are fully aware of the underlying topology of the core network so they can make informed forwarding decisions. The tunnelling encapsulation only serves the purpose of transporting protocols/payloads, that aren't native in the core, from edge-to-edge. The tunnelling function doesn't try to control or have to take responsibility for the selecting paths taken across the core.
This is just is a slight move of the core/edge boundary. Core switching capabilities (MPLS) have been added to edge devices which were pure terminal-devices from an ATM-perspective. The MPLS-cloud is just as obscure as ATM to a non-MPLS-speaking IP-device. //per