UEs IPv4, IPv6, and IPv4v6 Support

The UPF supports UE's IPv4, IPv6, and IPv4v6 sessions.

The N4 Session Establishment and Modification procedure for IPv6 sessions is the same as for IPv4 sessions. After the session is established, the SMF sends Router Advertisement (RA) message to UE announcing the IPv6 prefix to be used for traffic. Optionally, to get the IPv6 parameter from SMF faster, the UE can also initiate IPv6 Router Solicitation (RS).

The N4 Session Establishment and Modification procedure for IPv4v6 Session are similar to the IPv4 or IPv6 sessions except for the allocation of two UE IP addresses - one for IPv4 and the other for IPv6. The SMF sends the Router Advertisement message to the UE announcing the IPv6 prefix used for traffic after the session is established. Optionally, the UE can also initiate the IPv6 Router Solicitation to receive the IPv6 parameter from the SMF quickly.