Wi-Fi attach

One of the prime features of the 5G core network is its capability to inter-work with different types of access networks, both 3GPP-based and non-3GPP-based. One such network is Wi-Fi. The 5G radio can coexist with Wi-Fi access to cover coverage gaps. Hence, denser access can be planned with complementing radio access technologies. This is how Wi-Fi and New Radio (5G radio) can complement each other and do not need to be treated as competing technologies.

Figure 7.29 – Wi-Fi attach – part 1

We will now go over the Wi-Fi attach procedure:

Step 1: The UE sends the IKE_SA_AUTH exchange message to ePDG (IWF-interworking function) to create the IPSec tunnel.

Step 2: The UE sends the IKE_SA_AUTH exchange message to the SMF+PGW-C as a GTP Create Session request by including the P-CSCF IPv4 or IPv6 request and DNS IPv4 or IPv6 container identifier in APCO IE options. The ePDG checks the UE capability information to determine whether...