❦ 29 juillet 2020 12:13 +03, Saku Ytti:
This is the solution Cumulus is advocating to its users, so I suppose they have some real users behind that. Juniper also supports RFC 5549 but, from the documentation, the forwarding part is done using lightweight tunnels.
I'm not sure if you claim otherwise, but no real 'tunneling' takes place, as far as I know, it's internal implementation detail having IPV6 next-hop for IPV4. I don't think there is any additional headers or any additional lookup or cost.
I didn't test, but the documentation states:
Starting in Release 17.3R1, Junos OS devices can forward IPv4 traffic over an IPv6-only network, which generally cannot forward IPv4 traffic. As described in RFC 5549, IPv4 traffic is tunneled from CPE devices to IPv4-over-IPv6 gateways. These gateways are announced to CPE devices through anycast addresses. The gateway devices then create dynamic IPv4-over-IPv6 tunnels to remote customer premises equipment and advertise IPv4 aggregate routes to steer traffic. Route reflectors with programmable interfaces inject the tunnel information into the network. The route reflectors are connected through IBGP to gateway routers, which advertise the IPv4 addresses of host routes with IPv6 addresses as the next hop.
https://www.juniper.net/documentation/en_US/junos/topics/topic-map/multiprot... If you have a pointer around the subject on Juniper, I would be quite interested! Thanks. -- Write and test a big program in small pieces. - The Elements of Programming Style (Kernighan & Plauger)