[Optional] FN-RG sends an IP address/prefix request to the W-AGF via the L2 connection established in clause 126.96.36.199
This IP address/prefix request can also be sent by FN-RG later in this procedure; the W-AGF may store this and complete the address allocation via 5GC after the PDU session setup. The means of carrying the IP address/prefix request/response between FN-BRG and W-AGF is defined in BBF WT-456 , WT-457  and between FN-CRG and W-AGF is defined in CableLabes WR-TR-5WWC-ARCH .
After the registration procedure is completed, the W-AGF may establish PDU session(s) on behalf of the FN-RG. The trigger for W-AGF to initiate a PDU establishment process is defined in BBF WT-456 , WT-457  and CableLabs WR-TR-5WWC-ARCH .
The W-AGF generates a PDU session ID and derives the parameters for the PDU Session (PDU Session type, S-NSSAI, DNN, SSC mode, etc.) based on signalling received from the FN-RG (DHCP, IPv6 RS, etc.), on local configuration, and on information received from the 5GC (e.g. during the Registration procedure or when received URSP rules) and stored on the W-AGF.
If W-AGF has received a DHCPv4/DHCPv6 request from the FN-RG, it may request a PDU Session with deferred IP address allocation.
The W-AGF sends a NAS PDU Establishment Request to the AMF. This request contains the PDU Session ID, and may contain a Requested PDU Session Type, a Requested SSC mode, 5GSM Capability PCO, SM PDU DN Request Container, Number of Packet Filters.
The W-AGF sends NAS PDU Establishment Request in a N2 Uplink NAS transport message (NAS message, User location information, W-AGF identities).
The W-AGF identities contains a list of Identifiers (i.e. FQDN or IP address) of N3 terminations at W-AGF and can be used by SMF in step 8 in TS 23.502, clause 188.8.131.52.1
as input to select an UPF.
The PDU session request is processed in the 5GC as per steps 2-11 of TS 23.502, clause 184.108.40.206.1
. These steps are for UPF selection and resource reservation/allocation in the UPF. With regard to TS 23.502
, an additional parameter is sent from AMF to SMF i.e. the list of Identifiers (i.e. FQDN or IP address) of N3 terminations at W-AGF received by the AMF from the W-AGF. The SMF can use it in step 8 for UPF selection as per TS 23.502, clause 220.127.116.11.1
The SMF responds via AMF as defined in step 11 of clause 18.104.22.168.1 of TS 23.502
with an N2 PDU Session Request that includes QoS profile(s), PDU Session ID, PDU Session Establishment Accept and the N3 tunnel endpoint information for the UPF. The differences with step 11/12 of TS 23.502, clause 22.214.171.124.1
The W-AGF shall ignore RSN if received from 5GC.
Based on its own policies, configuration and based on the QoS flows, QoS parameters received in the previous step, the W-AGF shall determine what W-UP resources are needed for the PDU session.
The W-AGF may, as defined in BBF WT-456 , WT-457  and CableLabs WR-TR-5WWC-ARCH , perform Access specific resource reservation with the AN, that is, it sets up the W-UP resources for the PDU session.
The W-AGF allocates AN N3 tunnel information for the PDU Session and includes the AN N3 tunnel endpoint information in the N2 PDU Session Setup Response message to the AMF.
The PDU session setup procedure is completed in 5GC. All steps after step 13 as specified in TS 23.502
figure 126.96.36.199.1 are executed.
If W-AGF requested deferred IP address allocation in step 1 and this was accepted by the network, the W-AGF sends on the user Plane of the PDU Session any DHCP or RS message received beforehand from the FN-RG to the 5GC to obtain the IP address/prefix.
W-AGF completes the IP address/prefix allocation with the FN-RG via the established L2 connection. If W-AGF did not request deferred IP address allocation in step 1a, the IP address/prefix sent back to the FN-RG is the UE IP address/prefix delivered in NAS message in step 2b. If W-AGF requested deferred IP address allocation in step 1a, the IP address/prefix sent back to the FN-RG is the UE IP address/prefix delivered via deferred IP address allocation procedures in step 6a.