Mark Tinka wrote:
MPLS with nested labels, which is claimed to scale because nesting represents route hierarchy, just does not scale because source hosts are required to provide nested labels, which means the source hosts have the current most routing table at destinations, which requires flat routing without hierarchy or on demand, that is, flow driven, look up of detailed routing tables of destinations at a distance.
This detail is limited to PE devices (ingress/egress).
As it requires
flat routing without hierarchy or on demand, that is, flow driven, look up of detailed routing tables of destinations at a distance.
MPLS is just broken.
You don't need to carry a BGP table in the P devices (core), as only label swapping is required.
So?
Fair point, it is a little heavy for an edge box,
Requiring
flat routing without hierarchy
means it is fatally heavy for intermediate boxes.
or on demand, that is, flow driven, look up of detailed routing tables of destinations at a distance.
means it is fatally heavy for edge boxes.
In the end, having a flat L2 domain was just simpler.
That's totally against the CATENET model. Why, do you think, NHRP was abandoned?
we've never ran into an issue carrying thousands of IS-IS IPv4/IPv6 routes this way.
Thousands of? Today with so powerful CPUs, that is a small network. So? Masataka Ohta