On 11/Jun/20 14:43, Gert Doering wrote:

Not "in addition to" but "to throw out the IPv4 part" :-)

That's another view-point, yes. There are plenty of networks that can't afford to keep buying IPv4 on the open market. They want to go single-stack IPv6. Today, you would need to build a 6PE network if you want MPLS support in your IPv6-only network, which still requires IPv4. Private IPv4 address space works, but some people like it, some don't, and more importantly, you still carry around IPv4. You could try the SRv6 gravy, but now you probably need new kit. What's the SRv6 business-case? Well, one would say you save millions of $$ not buying IPv4, but now you've spent money supporting SRv6. LDPv6 can be supported by any platform that supports MPLS today. No money out the door. Cisco would need to develop code for both LDPv6 and SRv6 anyway, so no harm done on that side. As we used to say in Vladivostok, "It's simple physics :-)".

(If I had LDPv6 today, I wouldn't actually change the existing network today. But for the next round of rebuilding things, it would be something to consider...)

Give your favorite Cisco AM a shout-out. I promise, they are probably too young to remember your 6500/7600 tickets :-). Mark.