Mark Tinka wrote:
I wouldn't agree.
MPLS is a purely forwarding paradigm, as is hop-by-hop IP.
As the first person to have proposed the forwarding paradigm of label switching, I have been fully aware from the beginning that: https://tools.ietf.org/html/draft-ohta-ip-over-atm-01 Conventional Communication over ATM in a Internetwork Layer The conventional communication, that is communication that does not assume connectivity, is no different from that of the existing IP, of course. special, prioritized forwarding should be done only by special request by end users (by properly designed signaling mechanism, for which RSVP failed to be) or administration does not scale.
Even with hop-by-hop IP, you need the edge to be routing-aware.
The edge to be routing-aware around itself does scale. The edge to be routing-aware at the destinations of all the flows over it does not scale, which is the problem of MPLS. Though the lack of equipment scalability was unnoticed by many, thanks to Moore' law, inscalable administration costs a lot. As a result, administration of MPLS has been costing a lot.
I wasn't at the table when the MPLS spec. was being dreamed up,
I was there before poor MPLS was dreamed up.
If you can tell me how NOT running MPLS affords you a "hierarchical, scalable" routing table, I'm all ears.
Are you saying inter-domain routing table is not "hierarchical, scalable" except for the reason of multihoming? As for multihoming problem, see, for example: https://tools.ietf.org/html/draft-ohta-e2e-multihoming-03
Whether you forward in IP or in MPLS, scaling routing is an ever clear & present concern.
Not. Even without MPLS, fine tuning of BGP does not scale. However, just as using plain IP router costs less than using MPLS capable IP routers, BGP-only administration costs less than BGP and MPLS administration. For better networking infrastructure, extra cost should be spent for L1, not MPLS or very complicated technologies around it. Masataka Ohta