
On 19/Jun/20 17:13, Robert Raszuk wrote:
So I think Ohta-san's point is about scalability services not flat underlay RIB and FIB sizes. Many years ago we had requests to support 5M L3VPN routes while underlay was just 500K IPv4.
Ah, if the context, then, was l3vpn scaling, yes, that is a known issue. Apart from the global table vs. VRF parity concerns I've always had (one of which was illustrated earlier this week, on this list, with RPKI in a VRF), the other reason I don't do Internet in a VRF is because it was always a trade-off: - More routes per VRF = fewer VRF's. - More VRF's = fewer routes per VRF. Going forward, I believe the l3vpn pressures (for pure VPN services, not Internet in a VRF) should begin to subside as businesses move on-prem workloads to the cloud, bite into the SD-WAN train, and generally, do more stuff over the public Internet than via inter-branch WAN links formerly driven by l3vpn. Time will tell, but in Africa, bar South Africa, l3vpn's were never a big thing, mostly because Internet connectivity was best served from one or two major cities, where most businesses had a branch that warranted connectivity. But even in South Africa (as the rest of our African market), 98% of our business is plain IP. The other 2% is mostly l2vpn. l3vpn's don't really feature, except for some in-house enterprise VoIP carriage + some high-speed in-band management. Even with the older South African operators that made a killing off l3vpn's, these are falling away as their customers either move to the cloud and/or accept SD-WAN thingies.
Last - when I originally discussed just plain MPLS with customers with single application of hierarchical routing (no BGP in the core) frankly no one was interested. Till L3VPN arrived which was game changer and run for new revenue streams ...
The BGP-free core has always sounded like a dark art. More so in the days when hardware was precious, core routers doubled as inline route reflectors and the size of the IPv4 DFZ wasn't rapidly exploding like it is today, and no one was even talking about the IPv6 DFZ. Might be useful speaking with them again, in 2020 :-). Mark.