APPARATUS FOR ETHERNET TRAFFIC AGGREGATION OF RADIO LINKS

• US 20110116443A1
• Filed: 11/13/2009
• Published: 05/19/2011
• Est. Priority Date: 11/13/2009
• Status: Active Grant

• Current Assignee: Exalt Wireless Incorporated
• Original Assignee: Exalt Communications Incorporated
• Inventors: Zhang, Yongmin, Smidth, Peter, Yu, Jungji
• Granted Patent: US 8,611,356 B2
• Time in Patent Office: Days
• US Class Current: 370/328
• CPC Class Codes: H04L 12/413 with random access, e.g. carrier-sense multiple-access with collision detection [CSMA-CD]
• CPC Class Codes: H04L 47/10 Flow control; Congestion control
• CPC Class Codes: H04L 47/125 by balancing the load, e.g. traffic engineering
• CPC Class Codes: H04L 47/34 ensuring sequence integrity, e.g. using sequence numbers

Abstract

A multi-radio device system includes a set of sending radio devices and a set of receiving radio devices. Among the sending radio devices is a load-balancing radio device that receives data packets from an originating network. The load-balancing radio device labels data packets with sequence numbers and distributes the labeled data packets among the sending radio devices based on the relative capacities and statuses of those sending radio devices. The sending radio devices transmit the labeled data packets to the receiving radio devices. The receiving radio devices send the labeled data packets to an aggregating radio device within the set of receiving radio devices. The aggregating radio device uses the sequence numbers to ensure that the data packets are forwarded to a destination network in the correct order, extracting original data packets from the labeled data packets before forwarding the original data packets on toward the destination network.

Claims

1. An aggregating radio device comprising:

a first determiner that determines whether all queues of a plurality of queues contain data packets that do not indicate an expected next sequence number;

a dequeuer which, in response to a determination by the first determiner that all queues of the plurality of queues contain data packets that do not indicate the expected next sequence number, removes, from one queue of the plurality of queues, a particular data packet that contains a particular sequence number that is closest to the expected next sequence number among sequence numbers that are indicated by data packets in the plurality of queues;

a processor that processes the particular data packet; and

a sender that sends at least a portion of the particular data packet toward a destination indicated within the particular data packet.

2. The aggregating radio device of claim 1, wherein the processor decapsulates, from a payload field of the particular data packet, an original data packet that indicates the destination through a destination address field of the original data packet;

wherein the sender sends the original data packet toward a device that is indicated within the destination address field;

wherein the particular sequence number is contained in the payload field of the particular data packet.

3. The aggregating radio device of claim 2, wherein each queue of the plurality of queues corresponds to a separate port of a plurality of ports of the aggregating radio device;

wherein each port of the plurality of ports of the aggregating radio device is connected to a different receiving device of a plurality of receiving devices; and

wherein, for each particular queue of the plurality of queues, the particular queue becomes populated only with data packets that are received by a particular receiving device, of the plurality of receiving devices, which is connected to a particular port, of the plurality of ports, which corresponds to the particular queue.

4. The radio device of claim 2, wherein the radio device receives a particular data packet from a switch to which the radio device is connected;

wherein the radio device determines whether a MAC address specified within the particular data packet matches a particular MAC address, from a set of reserved MAC addresses, that is assigned to the radio device and to no other radio devices that are connected to the switch; and

wherein the radio device only transmits the particular data packet over radio waves if the MAC address specified within the particular data packet matches the particular MAC address that is assigned to the radio device.

5. The load-balancing device of claim 2, wherein the load-balancing radio device encapsulates a particular data packet within an encapsulating data packet that indicates a MAC address of a particular radio device that (a) is connected to a switch that is interposed between the load-balancing radio device and the particular radio device and (b) was selected by the load-balancing radio device to transmit the particular data packet over radio waves;

and wherein the load-balancing radio device sends the encapsulating data packet to said switch.

6. The aggregating radio device of claim 1, wherein each receiving device of a plurality of receiving devices that are connected to the aggregating radio device is a radio device that receives data packets over radio waves.

7. The aggregating radio device of claim 1, further comprising:

a timer which, in response to a determination that (a) no queue of a plurality of queues contains a data packet that indicates an expected next sequence number and (b) at least one empty queue of the plurality of queues of the aggregating radio device does not currently contain any data packet, causes the aggregating radio device to wait for a specified period of time for the data packet that indicates the expected next sequence number to arrive in said empty queue; and

a second determiner that determines, after the aggregating radio device has waited for the specified period of time, whether any queue of the plurality of queues contains a data packet that indicates the expected next sequence number; and

wherein the aggregating radio device, in response to a determination by the second determiner that no queue of the plurality of queues contains a data packet that indicates the expected next sequence number after waiting for the specified period of time, (a) removes a particular data packet from one queue of the plurality of queues, (b) decapsulates an original data packet from within the particular data packet, and (c) sends the original data packet towards a destination indicated by the original data packet.

8. The aggregating radio device of claim 7, wherein, after the aggregating radio device has removed the particular data packet from a queue, and in response to the aggregating radio device determining that no queue of the plurality of queues contains a subsequent data packet indicating a subsequent expected next sequence number, the aggregating radio device determines whether said empty queue has contained any data packet since said aggregating device waited for said specified period of time;

and

in response to determining that said empty queue has not contained any data packet since said aggregating device waited for said specified period of time, said aggregating device (1) does not wait for said subsequent data packet to arrive in any queue of the plurality of queues and (2) removes a data packet other than said subsequent data packet from one queue of the plurality of queues.

9. The aggregating radio device of claim 1, further comprising:

a receiver that receives a particular data packet at the aggregating device;

wherein the determiner determines whether a priority level indicated by the particular data packet is a specified priority level; and

wherein the aggregating radio device, in response to a determination that the priority level is the specified priority level, places the particular data packet into a particular queue of the plurality of queues;

wherein the particular queue does not contain any data packets that are not of the specified priority level.

10. The aggregating radio device of claim 1, further comprising:

a receiver that receives a particular data packet at the aggregating device;

wherein the first determiner determines whether a priority level indicated by the particular data packet is a specified priority level; and

wherein the aggregating radio device, in response to determining that the priority level is not the specified priority level, sends at least a portion of the particular data packet toward a destination indicated within the particular data packet without placing the data packet into any queue of the plurality of queues at any time.

11. The load-balancing device of claim 1, wherein the load-balancing device stores a mapping between (a) a particular quality of service priority level and (b) at least one of:

(1) a MAC address, (2) a port identifier, and (3) a VLAN priority;

wherein the load-balancing device is configured to load-balance only the particular quality of service priority level; and

wherein the particular quality of service priority level is one of a plurality of different quality of service priority levels, each level of which is mapped to a different set of characteristics.

12. A radio device system comprising:

A load balancing device and an aggregating radio device. The load balancing device periodically sends a message to the aggregating radio device. The aggregating radio device monitors this message and computes the radio link status. The aggregating radio device periodically sends, through at least one port of a plurality of ports of the aggregating radio device, a status message that informs a load-balancing device that a particular pair of communicating radio devices, which transmit and receive the status message, is functional; and

wherein the particular pair is associated with said at least one port.

13. The radio device system of claim 12, wherein the load-balancing device determines an error rate of a particular radio device of a plurality of radio devices;

wherein, in response to a determination that the error rate exceeds a specified threshold, the load-balancing device at least temporarily stops sending data packets to the particular radio device; and

wherein the load-balancing device determines the error rate of the particular radio device based at least in part on a count of status messages that the particular radio device transmitted over the air and that were also received by the aggregating radio device.

14. The radio device system of claim 12, wherein the load-balancing device determines an error rate of a particular radio device of a plurality of radio devices;

wherein, in response to a determination that the error rate exceeds a specified threshold, the load-balancing device determines whether error rates of all of the radio devices of the plurality of radio devices exceed the specified threshold; and

in response to determining that the error rates of all of the radio devices of the plurality of radio devices exceed the specified threshold, the load-balancing radio device continues to send data packets through the particular radio device even though the error rate of the particular radio device exceeds the specified threshold.

15. A radio device system comprising a radio device that comprises:

a queue that receives data packets that are sent to the radio device from a load-balancing device;

a determiner that determines (a) whether current queue depth is at least as great as a specified upper threshold and (b) whether current queue depth is at least as small as a specified lower threshold;

wherein, in response to the determiner determining that current queue depth is at least as great as the upper threshold, the radio device sends, to the load-balancing device, a message that instructs the load-balancing device to at least temporarily stop sending packets to the radio device; and

wherein, in response to the determiner determining that current queue depth is at least as small as the lower threshold, the radio device sends, to the load-balancing device, a message that instructs the load-balancing device to resume sending packets to the radio device.

16. The radio device system of claim 15, wherein:

the load-balancing device comprises a plurality of ports through which the load-balancing device (a) sends data packets to a plurality of radio devices connected with the ports and (b) receives flow control messages from the plurality of radio devices; and

a separate timeout clock for each port of the plurality of ports;

wherein, in response to receiving a “

stop”

flow control message through a particular port of the plurality of ports, the load-balancing device stops sending data packets through the particular port and starts a particular timeout clock that is associated with the particular port;

wherein, after receiving the “

stop”

flow control messages through the particular port, the load-balancing device does not send any further data packets through the particular port until either (a) the load-balancing device receives, through the particular port, a “

resume”

flow control message or (b) the particular timeout clock expires; and

wherein, in response to either (a) receiving, through the particular port, the “

resume”

flow control message or (b) the particular timeout clock expiring, the load-balancing device resumes sending data packets through the particular port.

17. The radio device system of claim 16, wherein, in response to receiving another “

stop”

flow control message through the particular port, the load-balancing device determines whether the load-balancing device has already stopped sending data packets over all ports of the plurality of ports other than the particular port; and

, in response to the load-balancing device determining that the load-balancing device has already stopped sending data packets over all ports of the plurality of ports other than the particular port, the load-balancing device resumes sending data packets over all ports of the plurality of ports.