Method and System for Decrementing Account Balance Based on Air-Interface Resource Information

1. A method comprising: at a gateway that provides connectivity between an access network and a transport network, receiving a message that was originated by a wireless communication device (WCD) being served by the access network; the gateway identifying a given air-interface resource on which the access network is serving the WCD, wherein the given air-interface resource is selected from the group consisting of a frequency band, at least one frequency channel, and at least one Orthogonal Frequency Division Multiple Access (OFDMA) resource block; after receiving the message, the gateway using the given air-interface resource to determine one or more rules for decrementing an account balance associated with the WCD; and the gateway decrementing the account balance associated with the WCD in accordance with the determined one or more rules.

2. The method of claim 1 , wherein the message includes an indication of the given air-interface resource, and wherein identifying the given air-interface resource on which the access network is serving the WCD comprises identifying the given air-interface resource based on the indication.

3. The method of claim 2 , wherein the indication of the given air-interface resource is located in a header of the message.

4. The method of claim 3 , wherein the header of the message comprises a general packet radio service tunneling protocol (GTP-U) extension header.

5. The method of claim 1 , wherein the given air-interface resource comprises a given frequency band, wherein the one or more rules comprise a respective rule corresponding to each of one or more frequency bands, and wherein determining the one or more rules for decrementing the account balance associated with the WCD comprises matching the given frequency band with one of the one or more frequency bands.

6. The method of claim 1 , wherein determining the one or more rules for decrementing the account balance associated with the WCD comprises using the given air-interface resource to obtain the one or more rules from a database of rules maintained by the gateway.

7. A method comprising: at a gateway that provides connectivity between an access network and a transport network, receiving a message that was originated by a wireless communication device (WCD) being served by the access network; the gateway identifying a given air-interface resource on which the access network is serving the WCD; after receiving the message, the gateway using the given air-interface resource to determine one or more rules for decrementing an account balance associated with the WCD, wherein determining the one or more rules for decrementing the account balance associated with the WCD comprises (i) sending a request for the one or more rules to a policy charging and rules function (PCRF), wherein the request includes an indication of the given air-interface resource, and (ii) as a result of sending the request, receiving the one or more rules from the PCRF; and the gateway decrementing the account balance associated with the WCD in accordance with the determined one or more rules.

8. The method of claim 1 , further comprising: the gateway detecting a change in the given air-interface resource on which the access network is serving the WCD from the given air-interface resource to a second air-interface resource; and the gateway adjusting the one or more rules for decrementing the account balance of the WCD from a first set of rules associated with the given air-interface resource to a second set of rules associated with the second air-interface resource.

9. A method comprising: at an access network, serving a wireless communication device (WCD) with telecommunication service, wherein the access network maintains an account balance associated with the WCD; the access network identifying a given air-interface resource on which the access network is serving the WCD; the access network using the given air-interface resource to determine one or more rules for decrementing the account balance associated with the WCD; the access network decrementing the account balance associated with the WCD in accordance with the determined one or more rules; the access network detecting a change in the given air-interface resource on which the access network is serving the WCD from the given air-interface resource to a second air-interface resource; and the access network adjusting the one or more rules for decrementing the account balance of the WCD from a first set of rules associated with the given air-interface resource to a second set of rules associated with the second air-interface resource.

10. The method of claim 9 , wherein the given air-interface resource comprises a frequency band.

11. The method of claim 9 , wherein the given air-interface resource comprises at least one frequency channel on which the access network is serving the WCD.

12. A gateway comprising: a network communication interface configured to provide connectivity with an access network; a processing unit; data storage; and program instructions stored in the data storage and executable by the processing unit to carry out functions comprising: receiving a message that was originated by a wireless communication device (WCD) being served by the access network, wherein the message includes an indication of the given air-interface resource located in a header of the message; identifying a given air-interface resource on which the access network is serving the WCD, wherein identifying the given air-interface resource on which the access network is serving the WCD comprises identifying the given air-interface resource based on the indication; after receiving the message, using the given air-interface resource to determine one or more rules for decrementing an account balance associated with the WCD; and decrementing the account balance associated with the WCD in accordance with the determined one or more rules.

13. The gateway of claim 12 , wherein the given air-interface resource comprises a given frequency band, wherein the one or more rules comprise a respective rule corresponding to each of one or more frequency bands, and wherein determining the one or more rules for decrementing the account balance associated with the WCD comprises matching the given frequency band with one of the one or more frequency bands.

14. The gateway of claim 12 , wherein determining the one or more rules for decrementing the account balance associated with the WCD comprises using the given air-interface resource to obtain the one or more rules from a database of rules maintained by the gateway.

15. The gateway of claim 12 , wherein determining the one or more rules for decrementing the account balance associated with the WCD comprises: sending a request for the one or more rules to a policy charging and rules function (PCRF), wherein the request includes an indication of the given air-interface resource; and as a result of sending the request, receiving the one or more rules from the PCRF.