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Marcus Keane
Hi Rich, I'm glad the article was helpful for you. You ask a good question about SD-WAN. Most of our tail-site connectivity is through carrier-provided L3VPNs with centralised internet egress. Having local egress makes this interesting. If we assume about 50% of our internet traffic is IPv6(which is what we see internally), then maintaining a centralised NAT64 reduces the potential benefits of SD-WAN. You bring up a good point about public v4 ranges. Decentralising the NAT64 only makes sense if we can get internet service(and addresses) from a single carrier(assuming they could give us small components out of an aggregate). To be honest, we haven't worked this out fully. But it's an interesting problem. :-) Marcus