Method and apparatus of IP flow mobility in 4G wireless communication networks
A method to realize IP flow mobility (IFOM) between 3GPP access and non-3GPP access over GTP based interfaces is proposed. A user equipment is connected to a PDN-GW via a 3GPP access network and a non-3GPP access network. The UE transmits an IFOM triggering message to the PDN-GW, which selects IP flows to be moved based on EPS bearer ID and IP flow description. The PDN-GW sends an Update Bearer Request to a WAG or ePDG, and updates its mapping table if the Update Bearer Request is successful. The UE also updates its mapping table upon receiving an IFOM acknowledgement from the WAG or ePDG. The PDN-GW initiates a 3GPP bearer modification procedure to move the selected IP flows.
1. A method comprising:
receiving an IP flow mobility (IFOM) triggering message by a packet data network gateway (PDN-GW), wherein the IFOM triggering message comprises an IFOM flag, a target radio access technology (RAT) type, an EPS bearer ID, a Quality of Service (QoS) policy, and a traffic aggregation description (TAD);
selecting IP flows based on the IFOM triggering message and transmitting an update bearer request to a wireless access gateway (WAG) or an evolved packet data gateway (ePDG);
updating a mapping table having one or more mapping entries if the update bearer request is successful, wherein each mapping entry is updated to indicate to which RAT type each IP flow is directed; and
initiating a 3GPP bearer modification procedure to move the selected IP flows.
2. The method of claim 1 , wherein the IP flows are selected based on the TAD describing the IP flows to be moved to the target RAT type.
3. The method of claim 1 , wherein the IP flows are selected based on the EPS bearer ID corresponds to a QoS class, and wherein all IP flows carried in the EPS bearer ID are to be moved to the target RAT type.
4. The method of claim 1 , wherein the mapping table comprises IP flow descriptions, and corresponding EPS bearer IDs, GTP tunnel IDs, RAT types and UE IDs.
5. The method of claim 1 , wherein the selected IP flows are moved from 3GPP access to non-3GPP access with GTP-based interface.
6. The method of claim 5 , wherein the update bearer request is a create bearer request to create a new bearer that satisfies the QoS policy defined for the selected IP flows, and wherein the create bearer request comprises the new bearer ID and a corresponding GTP tunnel ID.
7. The method of claim 1 , wherein the selected IP flows are moved from non-3GPP access with GTP-based interface to 3GPP access.
8. The method of claim 7 , wherein the update bearer request is a delete bearer request to delete bearers corresponding to the selected IP flows moved to 3GPP access.
9. A method comprising:
transmitting an IP flow mobility (IFOM) triggering message by a wireless access gateway (WAG), wherein the IFOM triggering message comprises an IFOM flag, a target radio access technology (RAT) type, an EPS bearer ID, a Quality of Service (QoS) policy, and a traffic aggregation description (TAD);
receiving an update bearer request from a packet data network gateway (PDN-GW) to modify S2a bearers for selected IP flows to be moved;
determining mapping traffic flows to the S2a bearers and transmitting an update bearer response to the PDN-GW to acknowledge the S2a bearer modification; and
transmitting an IFOM acknowledgement to a user equipment (UE).
10. The method of claim 9 , wherein the selected IP flows are determined based on the TAD or the EPS bearer ID.
11. The method of claim 9 , wherein the selected IP flows are moved from 3GPP access to non-3GPP access with GTP-based S2a interface.
12. The method of claim 11 , wherein the update bearer request is a create bearer request to create a new S2a bearer that satisfies the QoS policy defined for the selected IP flows, and wherein the create bearer request comprises the new S2a bearer ID and a corresponding GTP tunnel ID.
13. The method of claim 9 , wherein the selected IP flows are moved from non-3GPP access with GTP-based S2a interface to 3GPP access.
14. The method of claim 13 , wherein the update bearer request is a delete bearer request to delete S2a bearers corresponding to the selected IP flows moved to 3GPP access.
15. A method comprising:
connecting to a packet data network gateway (PDN-GW) by a user equipment (UE) via a 3GPP access network and a non-3GPP access network;
transmitting an IP flow mobility (IFOM) triggering message that comprises an IFOM flag, a target radio access technology (RAT) type, an EPS bearer ID, a Quality of Service (QoS) policy, and a traffic aggregation description (TAD);
receiving an IFOM acknowledgement from an evolved packet data gateway (ePDG); and
updating a mapping table having one or more mapping entries, wherein each mapping entry is updated to indicate to which RAT type each IP flow is directed.
16. The method of claim 15 , wherein the UE determines IFOM based on IP flow, and wherein the TAD includes one or more IP flows to be moved to the target RAT type.
17. The method of claim 15 , wherein the UE determines IFOM based on QoS class, and wherein all IP flows carried in the EPS bearer ID are to be moved to the target RAT type.
18. The method of claim 15 , wherein the mapping table comprises IP flow descriptions and corresponding EPS bearer IDs and RAT types.
19. The method of claim 15 , wherein the IFOM triggering message is an IFOM-enhanced IKEv2 message.
20. The method of claim 15 , wherein the IFOM acknowledgement is an IFOM-enhanced IKEv2 message.