Method and apparatus for efficiently performing congestion control in mobile communication system network

1. A method performed by a network apparatus, the method comprising:

detecting a congestion;

selecting a first internet protocol (IP) flow among a plurality of IP flows for a congestion control based on counter values of each of the plurality of IP flows;

determining whether the congestion control is supported for the first IP flow based on a first downlink packet of the first IP flow;

identifying a first uplink packet of a second IP flow in case that the congestion control is supported for the first IP flow;

updating a congestion-related field of a header of the first uplink packet from a first value to a second value, wherein the congestion-related field of the header of the first uplink packet indicates a reduction of a transmission window related to the first IP flow;

transmitting the first uplink packet including the congestion-related field with the second value;

identifying whether a congestion window reduced flag is set to 1 in a second downlink packet of the first IP flow after transmitting the first uplink packet including the congestion-related field with the second value; and

transmitting a second uplink packet including the congestion-related field with the second value, in case that the congestion window reduced flag is not set to 1 in the second downlink packet of the first IP flow.

2. The method of claim 1 , wherein the congestion control is supported in case that an explicit congestion notification (ECN) field of an IP header of the first downlink packet of the first IP flow is 01 or 10.

3. The method of claim 1 , further comprising:

updating an ECN field of the first downlink packet of the first IP flow from 01 or 10 to 11 in case that the congestion control is supported for the first IP flow.

4. The method of claim 1 ,

wherein the congestion-related field comprises an ECN-echo (ECE) field of a transmission control protocol (TCP) header, and

wherein an ECE flag is set in the ECE field to indicate that the congestion is detected.

5. The method of claim 2 , further comprising:

determining that congestion is detected in an upper node in case that the ECN field of the IP header of the first downlink packet received from the upper node is 11,

wherein the congestion-related field is updated based on a detection of the congestion in the upper node.

6. The method of claim 1 , wherein an ECN field of the first downlink packet is identified only in case that the congestion is detected.

7. The method of claim 1 , wherein the first uplink packet is selected based on at least one of a quality of service (QoS) policy.

8. The method of claim 1 , wherein the network apparatus comprises at least one of a base station, a router, or a gateway.

9. A network apparatus comprising:

a transceiver configured to transmit and receive a signal; and

a controller configured to:

detect a congestion,

select a first internet protocol (IP) flow among a plurality of IP flows for a congestion control based on counter values of each of the plurality of IP flows,

determine whether the congestion control is supported for the first IP flow based on a first downlink packet of the first IP flow,

identify a first uplink packet of a second IP flow in case that the congestion control is supported for the first IP flow,

update a congestion-related field of a header of the first uplink packet from a first value to a second value, wherein the congestion-related field of the header of the first uplink packet indicates a reduction of a transmission window related to the first IP flow,

transmit the first uplink packet including the congestion-related field with the second value,

identify whether a congestion window reduced flag is set to 1 in a second downlink packet of the first IP flow after transmitting the first uplink packet including the congestion-related field with the second value, and

transmit a second uplink packet including the congestion-related field with the second value, in case that the congestion window reduced flag is not set to 1 in the second downlink packet of the first IP flow.

10. The network apparatus of claim 9 , wherein the congestion control is supported in case that an explicit congestion notification (ECN) field of an IP header of the first downlink packet of the first IP flow is 01 or 10.

11. The network apparatus of claim 9 , wherein the controller is further configured to update an ECN field of the first downlink packet of the first IP flow from 01 or 10 to 11 in case that the congestion control is supported for the first IP flow.

12. The network apparatus of claim 9 ,

wherein the congestion-related field comprises an ECN-echo (ECE) field of a transmission control protocol (TCP) header, and

wherein an ECE flag is set in the ECE field to indicate that the congestion is detected.

13. The network apparatus of claim 10 , wherein the controller is further configured to:

determine that congestion is detected in an upper node in case that the ECN field of the IP header of the first downlink packet received from the upper node is 11; and

update the congestion-related field based on a detection of the congestion in the upper node.

14. The network apparatus of claim 9 , wherein the controller is further configured to identify an ECN field of the first downlink packet only in case that the congestion is detected.

15. The network apparatus of claim 9 ,

wherein the first uplink packet is selected based on at least one of a quality of service (QoS) policy.

16. The network apparatus of claim 9 , wherein the network apparatus comprises at least one of a base station, a router, or a gateway.