Access network device for managing queue corresponding to real time multimedia traffic characteristics and method thereof

• US 20050232154A1
• Filed: 01/05/2005
• Published: 10/20/2005
• Est. Priority Date: 01/05/2004
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Lee, Ji-hoon, Jeong, Seong-ho, Bang, Jong-ho, Oh, Se-Jong, Lee, Sung-hyuck
• Granted Patent: US 7,633,880 B2
• Time in Patent Office: Days
• US Class Current: 370/235
• CPC Class Codes: H04L 47/10 Flow control; Congestion control
• CPC Class Codes: H04L 47/28 in relation to timing considerations
• CPC Class Codes: H04L 47/32 by discarding or delaying data units, e.g. packets or frames
• CPC Class Codes: H04L 49/90 Buffering arrangements
• CPC Class Codes: H04L 49/9078 using an external memory or storage device

Abstract

A queue management method of an access network device includes receiving a packet, determining feasibility of a packet transmission within a delivery deadline allowed from a destination if the received packet is for real-time transmission, storing the packet in the transmission queue and transmitting the packet in sequential order of the storage when the packet transmission within the delivery deadline is feasible, and dropping the packet instead of storing the packet in the transmission queue when the packet transmission is determined infeasible. Accordingly, resources required for the packet transmission are saved.

Claims

1. A queue management method of an access network device storing a received packet in a transmission queue and transmitting the stored packet to a destination node in a storage order, the method comprising:

determining whether the packet is transmittable within a delivery deadline allowed for real-time traffic to the destination node; and

dropping the packet instead of storing the packet in the transmission queue when determined that the packet is not transmittable within the delivery deadline.

2. The queue management method of claim 1, wherein the determining of whether the packet is transmittable comprises:

calculating a maximum allowable queue length of the access network device for the transmission within the delivery deadline;

comparing the maximum allowable queue length with a current queue length of the transmission queue; and

determining the packet transmission infeasibility within the delivery deadline if the current queue length is greater than or equal to the maximum queue length.

3. The queue management method of claim 2, wherein the maximum allowable queue length is calculated using the delivery deadline, a total delay time from the packet transmission until the packet reception, and a transmission rate of the packet.

4. The queue management method of claim 2, further comprising:

storing the packet in the transmission queue when determined that the packet transmission is feasible within the delivery deadline;

storing a duplicate of the packet in a retransmission queue separately provided; and

transmitting the duplicate stored in the retransmission queue when a response packet indicating the destination node normally receives the packet is not received within a certain time after the packet transmission.

5. The queue management method of claim 4, wherein the maximum allowable queue length is calculated by waiting a predetermined period of time before the retransmission.

6. A queue management method of an access network device providing a mobile node with access to a network and, in which if a packet destined for the mobile node is received, the access network stores the packet in a transmission queue and transmitting the stored packet to the mobile node in a storage order, the method comprising:

the access network device receiving from the mobile node a handover initiation packet indicating a beginning of a handover when the handover of the mobile node initiates;

the access network device transmitting the packet to a new access network device when the packet destined for the mobile node is received after the reception of the handover initiation packet;

determining whether the packet is transmittable within a delivery deadline allowed for real-time transmission at the mobile node when the packet is for real-time transmission; and

dropping the packet instead of storing the packet in the transmission queue when determined that the packet transmission is infeasible within the delivery deadline.

7. The queue management method of claim 6, wherein the determining of whether the packet is transmittable comprises:

calculating a maximum queue length allowed of the access network device for the transmission within the delivery deadline;

comparing the maximum queue length with a current queue length of the transmission queue; and

determining the packet transmission within the delivery deadline to be infeasible if the current queue length is greater than or equal to the maximum queue length.

8. The queue management method of claim 7, further comprising:

the access network device receiving from the mobile node a handover completion packet indicating the handover is completed; and

dropping a packet instead of storing the packet in the transmission queue when the packet destined for the mobile node is received after the reception of the handover completion packet.

9. The queue management method of claim 8, wherein the maximum queue length is calculated using the delivery deadline, a total delay time from the packet transmission until the packet reception, and a transmission rate of the packet.

10. The queue management method of claim 9, further comprising:

storing the packet in the transmission queue when determined that the packet transmission is feasible within the delivery deadline;

storing a duplicate of the packet in a retransmission queue separately provided; and

transmitting the duplicate stored in the retransmission queue when a response packet indicating the destination node normally receiving the packet is not received within a certain time after the packet transmission.

11. The queue management method of claim 10, wherein the maximum allowable queue length is calculated by waiting a predetermined period of time before the retransmission.

12. An access network device comprising:

a packet input part receiving a packet destined for a certain node;

a transmission queue storing the packet received through the packet input part and transmitting the packet in a sequential order of the storage; and

a controller dropping the packet instead of storing the packet in the transmission queue when the received packet is for real-time transmission and a prediction of infeasibility to transmit the packet within a delivery deadline allowed for the real-time transmission packet to a destination node has been made.

13. The access network device of claim 12, wherein the controller calculates a maximum queue length of the packet transmission within the delivery deadline, compares the calculated maximum queue length with a current queue length, and determines the packet transmission within the delivery deadline to be infeasible if the current queue length is greater than or equal to the maximum queue length.

14. The access network device of claim 13, wherein the controller calculates the maximum queue length using the delivery deadline, a total delay time from the packet transmission until the packet reception, and a transmission rate of the packet.

15. The access network device of claim 13, further comprising a retransmission queue storing a duplicate of the packet and retransmitting the duplicate to the destination node when a response packet indicating the destination node normally receiving the packet is not received within a certain time.

16. The access network device of claim 15, wherein the controller calculates the maximum allowable queue length by waiting a predetermined period of time before the packet retransmission of the retransmission queue.

17. An access network device providing a mobile node with access to a certain network, the device comprising:

a packet input part receiving a packet destined for the mobile node and a handover initiation packet indicating a handover initiation of the mobile node;

a transmission queue storing the packet received after the reception of the handover initiation packet and transmitting the packet to a new access network device handover from the mobile node in a storage order; and

a controller dropping the packet instead of storing the packet in the transmission queue when the received packet is for real-time transmission and a prediction of infeasibility to transmit the packet within a delivery deadline allowed for the real-time transmission of the packet from a destination node has been made.

18. The access network device of claim 17, wherein the controller drops the received packet instead of storing the packet in the transmission queue if the packet destined to the mobile node is received after the packet input part receives from the mobile node a handover completion packet indicating that the handover is completed.

19. The access network device of claim 17, wherein the controller calculates a maximum queue length allowed for the packet transmission within the delivery deadline, compares the calculated maximum queue length with a current queue length, and determines the packet transmission within the delivery deadline to be infeasible if the current queue length is greater than or equal to the maximum queue length.

20. The access network device of claim 17, further comprising a retransmission queue storing a duplicate of the packet and retransmitting the duplicate to the destination node when a response packet indicating the destination node normally receiving the packet has not been received within a certain time.

21. An access network device comprising:

a packet input part receiving and/or transmitting packets to and/or from a node; and

a transmission queue storing the packets in a sequential order and dropping the packets after transmitting the packets to the node when the received packets are for real-time transmission and when predicted that the packets are not transmittable to the node within a predetermined time.

22. The access network device of claim 21, further comprising a retransmission queue storing duplicate packets of the packets stored in the transmission queue, wherein the duplicate packets are transmitted to the node if the packets stored in the transmission queue are not received by the node.

23. The access network device of claim 21, further comprising a controller controlling the storing of the packets in the sequential order based on whether the packets are transmittable to the node within the predetermined time.

24. The access network device of claim 21, wherein the transmission queue further includes a real-time transmission buffer storing the packets to be delivered in real-time and a non-real time transmission buffer storing the packets to be delivered in non real-time.

25. The access network device of claim 22, wherein the retransmission queue further includes a real-time transmission buffer and a non-real time transmission buffer storing the duplicate packets.

26. The access network device of claim 23, wherein the controller calculates a maximum queue length of the packets, compares the calculated maximum queue length with a current queue length, and determines whether the packets are transmittable within the predetermined time.