# RFC8950 Published articles for RFC8950. This is one page of public article previews, not the complete archive. Follow Next page to continue. Summaries are not the original full articles. ## RFC8950: Announce IPv4 with an IPv6 next-hop DevFeed: [RFC8950: Announce IPv4 with an IPv6 next-hop]() Original publisher: [Read original article]() Published: 2026-06-22T08:34:09Z Content type: tutorial Language: en Sources: [Personal blog of Anurag Bhatia]() Topics: [BGP]() Tags: [bgp](), [frr](), [ipv4](), [ipv6](), [rfc8950]() ### AI overview A tutorial-style explanation of RFC8950, which enables IPv4 routes to use IPv6 next hops over MP-BGP sessions. It describes IPv6-only backbone use cases, explains that the change affects the control plane while IPv4 remains unchanged on the wire, and outlines a Container Lab demonstration using FRR. ### Source excerpt For the last few days I have been playing with RFC8950 setup, which allows routing of IPv4 on top of IPv6. While logically it's quite simple, it has a very powerful application towards making "IPv4 an optional" feature riding on top of an IPv6 network (but without any tunnels!) Some of the interesting use cases: A large network can run IPv6 only everywhere on its core and leave IPv4 only on edge devices. This can work without customers doing any tweaking at their end. They still do things the old way but Backbone can run IPv6 only at its core. An IP transit backbone can run IPv6 only while exchanging IPv4 routes with its customers/peers/upstream over IPv6 sessions. So IPv4 as a "feature" stays but the network in itself is IPv6 only without the overhead of IPv4 interface config, BGP session config, firewall config, etc. An IXP can offer services without IPv4 essentually by using a (unique) IPv6 at the IX LAN & running route server to exchange both IPv4 & IPv6 routes over the IPv6 only session. Thus what 464XLAT did to the mobile networks - this has the potential to do that for the backbone networks. How does it work? Multi-protocol BGP (MP-BGP) supports announcement of IPv4 routes over IPv6 sessions with IPv4 next-hops and IPv6 routes over IPv4 sessions with IPv6 next-hops. RFC8950 extends this feature for IPv4 to have IPv6 next-hops. So for IPv4 address, next hop is IPv6, IPv6 reach works via usual NDP and IPv4 rides on ethernet frames to the same MAC as discovered by the NDP. Technically RFC8950 only impacts control plane decisions by using IPv6 as the control plane but keeps the data plane as it is. IPv4 stays IPv4 & goes as IPv4 over the wire unlike say some tunnel or 464xLAT etc. Hardware support As of now it's quite widely supported by a lot of routing platforms like Juniper JunOS, Cisco IOS XR, Nokia SR OS, Mikrotik, Huawei, BIRD, FRR etc. So, it is very likely supported if you are running a recent version of the OS. Demo lab Here's a fun lab with two customer