8.2.11 UE local IP address update on S2c over trusted Fixed Broadband Access

23.1393GPP3GPP system - fixed broadband access network interworkingRelease 17Stage 2TS

This clause is related to the case where the UE local IP address, e.g. the CoA in the DSMIP procedure, is updated.

Figure 8.2.11-1: UE local IP address changes on S2c over trusted Fixed Broadband Access

If dynamic policy provisioning over S9a is not deployed, the optional step 4 and 6 do not occur. Instead, the Fixed Broadband Access network may employ local policies.

1. UE attaches to EPC from BBF access network as described in clause 8.2.1. The IPSec tunnel and DSMIP tunnel are established between P-GW and UE.

2. The description of this step is the same as step 2 in clause 7.11.

3. Upon a change of the UE’s CoA, the UE sends the DSMIPv6 Binding Update message to the P-GW. In this step the P-GW gets the updated UE local IP address (i.e. the UE’s CoA if no NAT is deployed or the NATed CoA when NAT is deployed) and optionally the UDP source port number (if NAT is detected) of the DSMIPv6 binding update signalling.

4. The description of this step is the same as step B.2 in clause 7.11.

5. P-GW replies with the DSMIPv6 Binding Acknowledgement message to UE.

6. The description of this step is the same as step B.4 in clause 7.11.