Method and apparatus for routing calls

• US 20060083193A1
• Filed: 10/18/2004
• Published: 04/20/2006
• Est. Priority Date: 10/18/2004
• Status: Active Grant

• Current Assignee: Motorola Solutions, Inc.
• Original Assignee: Motorola, Inc. (Motorola Solutions, Inc.)
• Inventors: Dorenbosch, Jheroen P., Womack, James E., Segal, Niranjan N.
• Granted Patent: US 7,397,775 B2
• Time in Patent Office: Days
• US Class Current: 370/328
• CPC Class Codes: H04W 48/18 Selecting a network or a communication service
• CPC Class Codes: H04W 76/10 Connection setup
• CPC Class Codes: H04W 84/04 Large scale networks; Deep hierarchical networks
• CPC Class Codes: H04W 84/12 WLAN [Wireless Local Area Networks]
• CPC Class Codes: H04W 88/06 adapted for operation in multiple networks or having at least two operational modes, e.g. multi-mode terminals

Abstract

A communication unit (CU) (109, 111) network controller (113) and corresponding methods (603-609) are described that facilitate selectively routing calls. The CU includes a transceiver (403) suitable to support an air interface with a local area network (LAN) (101) and with a wide area network (WAN) (105) and a controller (405) that is coupled to and controlling the transceiver. These are each and collectively configured to determine when a bearer leg within the WLAN will not support a call attempt over the bearer leg and responsive to so determining, initiate the call over another bearer leg, e.g. within the LAN or the WAN. The determining includes, for example, receiving a message (703, 707, 713) that indicates or implies that the call can not be supported.

Claims

1. A wireless communication unit configured to facilitate routing calls, the communication unit comprising:

a transceiver suitable to support an air interface with a wireless local area network (WLAN) and with a wide area network (WAN); and

a controller coupled to and controlling the transceiver and configured to;

determine during a call setup process that a bearer leg within the WLAN will not support a call over the bearer leg at a requested Quality of Service (QoS); and

responsive to determining that the bearer leg will not support the call, initiate the call over the WAN.

2. The wireless communication unit of claim 1, wherein the controller with the transceiver is further configured to receive a message indicating the bearer leg will not support the call.

3. The wireless communication unit of claim 2, wherein the controller with the transceiver is further operable to receive the message comprising at least one of:

a SIP 5XX message, a precondition failure message, a call not acceptable message, a message indicating when the call can be retried, and a message indicating acceptable parameters for a call that the bearer leg will support.

4. The wireless communication unit of claim 3, wherein the message comprises one of a Session Initiation Protocol message and an H.323 message.

5. The wireless communication unit of claim 3 wherein the message indicating acceptable parameters for a call includes a quality of service (QoS) that is lower than normally used for the call and responsive to receiving this message, the controller with the transceiver initially accepts the call with the QoS, begins registration on the WAN, and then undertakes the initiate the call over the WAN.

6. The wireless communication unit of claim 1, wherein the controller with the transceiver is configured to initiate the call over the WAN by facilitating a routing of the call to the WAN.

7. The wireless communication unit of claim 6, wherein the controller with the transceiver is configured to facilitate the routing of the call to the WAN by at least one of calling a target number terminating on a network controller using the WAN and sending a contact address to the network controller.

8. A network controller for a local area network (LAN) that is loosely coupled to a wide area network (WAN) and arranged to facilitate appropriate routing of calls, the network controller comprising:

a public switched telephone network (PSTN) interface;

a LAN interface; and

a controller configured to;

determine that a bearer leg in the LAN will not support a call over the bearer leg at a requested Quality of Service (QoS); and

responsive to determining that the bearer leg will not support the call, facilitate re-routing the call to the WAN.

9. The network controller of claim 8 wherein the call is inbound to the network controller over the PSTN interface and the controller is further configured to:

determine that LAN resources are not available to support the call over the bearer leg; and

send, in cooperation with the LAN interface, a message to a communication unit that is the intended recipient of the call, the message indicating the call can not be supported.

10. The network controller of claim 9 wherein the message includes a lowered Quality of Service (QoS) parameter for the call and the controller in cooperation with the WLAN interface receives a response message from the communication unit, the response message indicating an alternate route for the call through the WAN.

11. The network controller of claim 9 wherein the message includes a lowered Quality of Service (QoS) parameter for the call and the controller in cooperation with the LAN interface receives a first response message from the communication unit, the first response message accepting the call with the lowered QoS and thereafter a second response message indicating an alternate route for the call through the WAN thereby initiating the re-routing the call through the WAN.

12. The network controller of claim 8 wherein the controller cooperatively with the LAN interface;

receives a message from a communication unit, the message attempting to initiate the call; and

sends, responsive to receiving the message, a response message further indicating at least one of a lack of capacity to support the call, a lower Quality of Service (QoS) to support the call, and a message indicating when the call can be retried.

13. The network controller of claim 12 wherein the controller cooperatively with the LAN interface after sending the response message further receives an other message from the communications unit, the other message indicating at least one of an alternate route for the call through the WAN, an acceptance of the call with the lower QoS for the call, and an other attempt to initiate the call.

14. A method in a wireless communication unit operating in a local area network (LAN) of selectively routing calls over alternative bearer paths, the method comprising:

detecting an attempt to initiate a call over the LAN;

determining that a bearer leg within the LAN will not support the call over the LAN at a requested Quality of Service (QoS); and

initiating the call over an other bearer leg, responsive to determining that the bearer leg will not support the call.

15. The method of claim 14, further comprising receiving a message indicating the bearer leg will not support the call.

16. The method of claim 15, wherein the message further comprises at least one of a SIP 5XX message, a precondition failure message, a call not acceptable message, a message indicating when the call can be retried, and a message indicating acceptable parameters for a call that the bearer leg will support.

17. The method of claim 15, wherein the message comprises one of a Session Initiation Protocol message and an H.323 message.

18. The method of claim 16 wherein the message indicating acceptable parameters for a call includes a quality of service (QoS) that is lower than normally used for the call and responsive to receiving this message, the method further comprises initially accepting the call with the QoS and thereafter undertaking the initiating the call over the other bearer leg routed via a WAN.

19. The method of claim 14, wherein the initiating the call over the other bearer leg further comprises at least one of initiating the call over at least one of another LAN bearer leg and facilitating a routing of the call through a WAN.

20. The method of claim 19, wherein the facilitating the routing of the call through the WAN further comprises calling a target number using the WAN, the target number terminating at a controller for the LAN and wherein the initiating the call over another LAN bearer leg further comprises associating with a different access point and sending a contact address to a network controller.