Mechanism for wireless access networks to throttle traffic during congestion

• US 20120263036A1
• Filed: 04/14/2011
• Published: 10/18/2012
• Est. Priority Date: 04/14/2011
• Status: Active Grant

• Current Assignee: RPX Corporation
• Original Assignee: Alcatel-Lucent SA (Nokia Corporation)
• Inventors: Barclay, Deborah L., Alfano, Frank M.
• Granted Patent: US 8,787,159 B2
• Time in Patent Office: Days
• US Class Current: 370/230
• CPC Class Codes: H04L 47/245 using preemption
• CPC Class Codes: H04W 28/0247 based on conditions of the access network or the infrastructure network central resource management H04W28/16
• CPC Class Codes: H04W 28/16 Central resource management; Negotiation of resources or communication parameters, e.g. negotiating bandwidth or QoS [Quality of Service]

Abstract

Exemplary methods and apparatuses are provided for throttling wireless traffic during congestion in radio access networks. Embodiments are provided that may assist service providers to reduce new requests for network resources during congestion and allow existing lower priority traffic to be pre-empted with a backoff time to allow a new request with higher priority traffic to be served. In response to a request for an additional connection to a radio access network from a terminal device that has one or more existing connections in the radio access network, an access network controller will compare a priority level of a requested connection to a priority level of other existing connections in the radio access network. The access network controller may reject or grant the request based on the comparison and send the terminal device a backoff time value and a congestion indicator.

Claims

1. A method comprising:

receiving at an access network controller a request from a core network component to provide an additional connection to a mobile communications device that has one or more existing connections to a radio access network managed by the access network controller;

determining at the access network controller whether at least a portion of the radio access network is in an overload condition; and

sending at the access network controller a first message to the core network component that comprises a congestion indicator and a time value during which congestion control is in effect.

2. The method of claim 1 further comprising generating the first message when a difference exists between a priority level of the requested additional connection and a priority level of existing connections in the radio access network.

3. The method of claim 2 wherein the generating the first message when a difference exists between the priority level of the requested additional connection and the priority level of the existing connections in the radio access network comprises:

retrieving a record of the priority level of at least one existing connection in the radio access network;

extracting the priority level of the requested additional connection from the request;

comparing the priority level of the requested additional connection to the priority level of the at least one existing connection in the radio access network; and

generating the first message to comprise a grant or a rejection indicator based on an outcome of the comparison.

4. The method of claim 3 wherein the first message comprises a rejection of the request when the priority level of the requested additional connection is lower than the priority level of the at least one existing connection in the radio access network.

5. The method of claim 3 wherein the first message comprises a grant of the request and a release of a lower priority pre-emptable bearer of the mobile communications device when the priority level of the requested additional connection is higher than the priority level of one of the one or more existing connections of the mobile communications device.

6. The method of claim 5 further comprising assigning the requested additional connection to the pre-empted bearer to activate the requested additional connection.

7. The method of claim 2 further comprising sending at the access network controller a second message to the core network component that comprises the time value during which congestion control is in effect and a release of a lower priority pre-emptable bearer of another mobile communications device when the priority level of the requested additional connection is higher than the priority level of at least one existing connection of the another mobile communications device in the radio access network.

8. The method of claim 1 wherein the first message comprises a grant of the request when the mobile communications device is not in an area impacted by congestion.

9. The method of claim 8 wherein the area impacted by the congestion is identified by an identifier selected from the group consisting of a location of the cell sites represented by a global position, a location area code and a MacroCell identity.

10. The method of claim 1 wherein the first message comprises a priority level under congestion control indicator.

11. An access network controller configured to manage one or more radio access networks, monitor the one or more radio access networks for overload conditions, and receive requests via a core network component initiated by one or more mobile communications devices for connections to the one or more radio access networks, the access network controller comprising:

a processor configured to compare a priority level of a connection requested by a mobile communications device having at least one existing connection in one of the one or more radio access networks to a priority level for connections in a set of one or more existing connections in the one of the one or more radio access networks when the access network controller determines that at least a portion of the one of the one or more radio access networks is in an overload condition, and configured to generate a first message when the comparison results in a determination that the priority level of the connection requested is not equal to the priority level of connections in the set of the one or more existing connections, wherein the first message comprises a congestion indicator and a time value during which congestion control is in effect; and

a transmitter configured to send the first message to the core network component.

12. The access network controller of claim 11 wherein the processor is further configured to retrieve a record of the priority level for the connections in the set of the one or more existing connections, extract the priority level of the connection requested from a received request, determine at least one difference between the priority level of the connection requested and the priority level of the connections of the set of the one or more existing connections, and generate the first message to comprise a grant or a rejection indicator based on an outcome of the comparison.

13. The access network controller of claim 11 further comprising a storage component connected to the processor, the storage component being configured to store at least one record of the priority level of the connections of the set of the one or more existing connections in the one or more radio access networks.

14. The access network controller of claim 11 wherein the first message comprises an identifier of an area impacted by congestion.

15. The access network controller of claim 11 wherein the first message comprises a priority level under congestion control indicator.

16. An access network controller comprising a non-transitory computer-readable storage medium having computer executable instructions for performing steps, comprising:

means for receiving a request from a core network component to provide an additional connection to a mobile communications device that has one or more existing connections to the radio access network;

means for determining that at least a portion of the radio access network is in an overload condition; and

means for sending a message to the core network component that comprises a congestion indicator and a time value during which congestion control is in effect.

17. A communications device comprising:

a processor configured to

generate, while having one or more connections to a radio access network, a first request to a core network for an additional connection to the radio access network,

initialize a timer to a time value received in a response to the first request, wherein the time value represents a duration of time during which congestion control is in effect for an area impacted by congestion, and

store a priority level under congestion control indicator received in the response to the first request; and

a memory component associated with the processor for storing the time value of the timer and the priority level under congestion control indicator.

18. The communications device of claim 17, wherein the processor is configured to generate a second request to the core network for another connection when a priority level of the second request is higher than the priority level under congestion control indicator.

19. The communications device of claim 17, wherein the processor is configured to clear the timer in response to a determination that the communications device has left the area impacted by congestion and to generate a renewed first request to the core network for the additional connection to the radio access network after the timer is cleared.

20. The communications device of claim 17, wherein the processor is configured to prevent another request to the core network for the additional connection to the radio access network while the timer has a non-zero value.