Method and nodes for handling a GTP-U direct tunnel

1. A method in a Core Network, CN, node for handling a General packet radio service Tunnelling Protocol-User plane, GTP-U, tunnel, the method comprising:

when the GTP-U tunnel is to be set up, the CN node transmitting a first message to a Radio Access Network, RAN, gateway, which first message comprises a request for information identifying the RAN gateway, wherein the CN node is one of a Serving General packet radio service Support Node, SGSN, and a Serving GateWay, SGW;

the CN node receiving a second message from the RAN gateway, which second message comprises the requested information identifying the RAN gateway; and

the CN node determining a first endpoint node and a second endpoint node of the GTP-U tunnel, wherein the first endpoint node is the RAN node and the second endpoint node is the RAN gateway, and wherein the GTP-U tunnel is a direct GTP-U tunnel between the first endpoint node and the second endpoint node.

2. The method according to claim 1 , further comprising:

transmitting a third message to the RAN gateway, which third message comprises information confirming that the RAN gateway is the second endpoint node for the GTP-U tunnel.

3. The method according to claim 1 , wherein the information identifying the RAN gateway is at least a part of a Fully qualified-Tunnel Endpoint Identifier, F-TEID.

4. The method according to claim 1 , wherein the GTP-U tunnel is a direct tunnel between the RAN node and the RAN gateway.

5. The method according to claim 1 , wherein the first message is a create bearer request message and the second and third messages are each a create bearer response message; or wherein the first message is a Network Requested Secondary Packet data protocol Context, NRSPC, request message and the second and third messages are each a NRSPC response message.

6. The method according to claim 5 , wherein the create bearer request message is a GTP-Control plane, GTP-C, create bearer request message and the create bearer response message is a GTP-C create bearer response message.

7. The method according to claim 1 , wherein the RAN node is one of a Radio Network Controller, RNC, a NodeB, NB, and an evolved Node B, eNB.

8. The method according to claim 1 , wherein the RAN node and the RAN gateway are each standalone nodes located in proximity of each other; or wherein the RAN gateway is co-located with the RAN node.

9. A computer program comprising instructions which, when executed on at least one processor, cause the at least one processor to carry out the method according to claim 1 .

10. A method in a Radio Access Network, RAN, gateway for handling a General packet radio service Tunnelling Protocol-User plane, GTP-U, tunnel, the method comprising:

when the GTP-U tunnel is to be set up, the RAN gateway receiving a first message from a Core Network, CN, node, which first message comprises a request for information identifying the RAN gateway, wherein the CN node is one of a Serving General packet radio service Support Node, SGSN, and a Serving GateWay, SGW;

the RAN gateway transmitting a second message to the CN node, which second message comprises the requested information identifying the RAN gateway; and

the RAN gateway directly tunneling user plane data via the GTP-U tunnel, wherein a RAN node is a first endpoint node of the GTP-U tunnel and the RAN gateway is a second endpoint node of the GTP-U tunnel, and wherein the GTP-U tunnel is a direct GTP-U tunnel between the first endpoint node and the second endpoint node.

11. The method according to claim 10 , further comprising:

receiving a third message from the CN node, which third message comprises information confirming that the RAN gateway is the second endpoint node for the GTP-U tunnel.

12. The method according to claim 10 , wherein the user plane data is directly tunneled via the GTP-U tunnel when the RAN node is without CN connection.

13. The method according to claim 10 , wherein the user plane data is directly tunneled via the GTP-U tunnel when the user plane data fulfills a criterion.

14. The method according to claim 10 , wherein the information identifying the RAN gateway is at least a part of a Fully qualified-Tunnel Endpoint Identifier, F-TEID.

15. The method according to claim 10 , wherein the GTP-U tunnel is a direct tunnel between the RAN node and the RAN gateway.

16. The method according to claim 10 , wherein the first message is a create bearer request message and the second and third messages are each a create bearer response message; or wherein the first message is a Network Requested Secondary Packet data protocol Context, NRSPC, request message and the second and third messages are each a NRSPC response message.

17. The method according to claim 16 , wherein the create bearer request message is a GTP-Control plane, GTP-C, create bearer request message and the create bearer response message is a GTP-C create bearer response message.

18. The method according to claim 10 , wherein the RAN node is one of a Radio Network Controller, RNC, a NodeB, NB, and an evolved Node B, eNB.

19. The method according to claim 10 , wherein the RAN node and the RAN gateway are each standalone nodes located in proximity of each other; or wherein the RAN gateway is co-located with the RAN node.

20. A computer program comprising instructions which, when executed on at least one processor, cause the at least one processor to carry out the method according to claim 10 .

21. A Core Network, CN, node for handling a General packet radio service Tunnelling Protocol-User plane, GTP-U, tunnel, the CN node comprising:

a memory;

processing circuitry coupled to the memory, the processing circuitry configured to:

when the GTP-U tunnel is to be set up, transmit a first message to a Radio Access Network, RAN, gateway, which first message comprises a request for information identifying the RAN gateway, wherein the CN node is one of a Serving General packet radio service Support Node, SGSN, and a Serving GateWay, SGW;

receive a second message from the RAN gateway, which second message comprises the requested information identifying the RAN gateway; and

determine a first endpoint node and a second endpoint node of the GTP-U tunnel, wherein the first endpoint node is the RAN node and the second endpoint node is the RAN gateway, and wherein the GTP-U tunnel is a direct GTP-U tunnel between the first endpoint node and the second endpoint node.

22. The CN node according to claim 21 , wherein the processing circuitry is further configured to:

transmit a third message to the RAN gateway, which third message comprises information confirming that the RAN gateway is the second endpoint node for the GTP-U tunnel.

23. The CN node according to claim 21 , wherein the information identifying the RAN gateway is at least a part of a Fully qualified-Tunnel Endpoint Identifier, F-TEID.

24. The CN node according to claim 21 , wherein the GTP-U tunnel is a direct tunnel between the RAN node and the RAN gateway.

25. The CN node according to claim 21 , wherein the first message is a create bearer request message and the second and third messages are each a create bearer response message; or wherein the first message is a Network Requested Secondary Packet data protocol Context, NRSPC, request message and the second and third messages are each a NRSPC response message.

26. The CN node according to claim 25 , wherein the create bearer request message is a GTP-Control plane, GTP-C, create bearer request message and the create bearer response message is a GTP-C create bearer response message.

27. The CN node according to claim 21 , wherein the RAN node is one of a Radio Network Controller, RNC, a NodeB, NB, and an evolved Node B, eNB.

28. The CN node according to claim 21 , wherein the RAN node and the RAN gateway are each standalone nodes located in proximity of each other; or wherein the RAN gateway is co-located with the RAN node.

29. A Radio Access Network, RAN, gateway for handling a General packet radio service Tunnelling Protocol-User plane, GTP-U, tunnel, the RAN gateway comprising:

a memory;

processing circuitry coupled to the memory, the processing circuitry configured to:

when the GTP-U tunnel is to be set up, receive a first from a Core Network, CN, node, which first message comprises a request for information identifying the RAN gateway, wherein the CN node is one of a Serving General packet radio service Support Node, SGSN, and a Serving GateWay, SGW;

transmit a second message to the CN node, which second message comprises the requested information identifying the RAN gateway; and

directly tunnel user plane data via the GTP-U tunnel, wherein a RAN node is a first endpoint node of the GTP-U tunnel and the RAN gateway is a second endpoint node of the GTP-U tunnel, and wherein the GTP-U tunnel is a direct GTP-U tunnel between the first endpoint node and the second endpoint node.

30. The RAN gateway according to claim 29 , wherein the processing circuitry is further configured to:

receive a third message to from the CN node, which third message comprises information confirming that the RAN gateway is the second endpoint node for the GTP-U tunnel.

31. The RAN gateway according to claim 29 , wherein the user plane data is directly tunneled via the GTP-U tunnel when the RAN node is without CN connection.

32. The RAN gateway according to claim 29 , wherein the user plane data is directly tunneled via the GTP-U tunnel when the user plane data fulfills a criterion.

33. The RAN gateway according to claim 29 , wherein the information identifying the RAN gateway is at least a part of a Fully qualified-Tunnel Endpoint Identifier, F-TEID.

34. The RAN gateway according to claim 29 , wherein the GTP-U tunnel is a direct tunnel between the RAN node and the RAN gateway.

35. The RAN gateway according to claim 29 , wherein the first message is a create bearer request message and the second and third messages are each a create bearer response message; or wherein the first message is a Network Requested Secondary Packet data protocol Context, NRSPC, request message and the second and third messages are each a NRSPC response message.

36. The RAN gateway according to claim 35 , wherein the create bearer request message is a GTP-Control plane, GTP-C, create bearer request message and the create bearer response message is a GTP-C create bearer response message.

37. The RAN gateway according to claim 29 , wherein the RAN node is one of a Radio Network Controller, RNC, a NodeB, NB, and an evolved Node B, eNB.

38. The RAN gateway according to claim 29 , wherein the RAN node and the RAN gateway are each standalone nodes located in proximity of each other; or wherein the RAN gateway is co-located with the RAN node.