Method of communicating in wireless network
The present invention relates to a handover method that a current coordinator transfers a coordinating function of controlling a network to a different device configuring the network. The present invention relates to a method of selecting an optimal device as a coordinator in selecting the different device using priority information decided by a prescribed evaluation reference. And, the present invention relates to a method of simplifying a procedure in a manner of transmitting relevant information together with a handover request message. In a wireless network including a coordinator, a secondary coordinator is decided in advance. If the coordinator is suddenly unable to perform a function, the present invention relates to a method of enabling the function of the coordinator to be performed by the decided secondary coordinator. Thus, a process for transferring the coordinating function without the handover process is called a recovery process. The present invention relates to the recovery method and a method of deciding a secondary coordinator to perform a recovery. In the method of deciding the secondary coordinator, a method of deciding a more proper coordinator using information on coordinator priority is provided.
1. A method of performing handover at a coordinator in a wireless network in which a high rate physical channel and a low rate physical channel are used for communication, the wireless network including at least one device, the method comprising:
receiving information associated with a priority of a device from the device when the device joins the wireless network;
transmitting a handover request message to the device if the priority of the device is higher than a priority of the coordinator based on the information received from the device;
receiving a response to the handover request message from the device;
broadcasting a first beacon on the low rate physical channel, the first beacon including identification information indicating that the device will be a new coordinator of the wireless network and number information indicating a number of beacons that the coordinator will broadcast before the handover occurs; and
broadcasting one or more beacons, corresponding to the number indicated by the number information, on the low rate physical channel, each of the one or more beacons including updated number information indicating a number of remaining beacons that the coordinator will send before the handover occurs, wherein the updated number information included in a last beacon among the one or more beacons is set to “0.”
2. The method of claim 1 , wherein the priority of the device has been determined by at least the device or the coordinator based on characteristics of the device.
3. The method of claim 1 , wherein the handover request message comprises handover-related information including at least information associated with reserved channel time blocks or information associated with characteristics of devices which comprise the wireless network.
4. The method of claim 1 , further comprising receiving a second beacon broadcast by the device after broadcasting a last beacon among the number of beacons and the coordinator terminates its coordinating function.
5. The method of claim 1 , wherein the response comprises information indicating that the device is ready to take over as the new coordinator of the wireless network.
6. The method of claim 1 , wherein the number information is included in a field of an information element included in each of the one or more beacons.
7. A method of performing handover at a device in a wireless network in which a high rate physical channel and a low rate physical channel are used for communication, the wireless network including a coordinator and at least one device, the method comprising:
transmitting information associated with a priority of the device to the coordinator when the device joins the wireless network;
receiving a handover request message from the coordinator if the priority of the device is higher than a priority of the coordinator based on the information transmitted to the coordinator;
transmitting a response to the handover request message to the coordinator;
receiving a first beacon on the low rate physical channel, the first beacon including identification information indicating that the device will be a new coordinator of the wireless network and number information indicating a number of beacons that the coordinator will broadcast before the handover occurs; and
receiving one or more beacons broadcast by the coordinator on the low rate physical channel, a number of the one or more beacons corresponding to the number of beacons indicated by the number information, each of the one or more beacons including updated number information indicating a number of remaining beacons that the coordinator will send before the handover occurs, wherein the updated number information included in a last beacon among the one or more beacons is set to “0.”
8. The method of claim 7 , wherein the handover request message comprises handover-related information including at least information associated with reserved channel time blocks or information associated with characteristics of devices which comprises the wireless network.
9. The method of claim 7 , further comprising broadcasting a second beacon after receiving a last beacon among the number of beacons broadcast by the coordinator and the coordinator terminates its coordinating function.
10. The method of claim 7 , wherein the response comprises information indicating that the device is ready to take over as the new coordinator of the wireless network.
11. The method of claim 7 , wherein the number information is included in a field of an information element included in each of the one or more beacons.
12. A coordinator in a wireless network in which a high rate physical channel and a low rate physical channel are used for communication, the wireless network including at least one device, wherein the coordinator is configured to:
receive information associated with a priority of a device from the device when the device joins the wireless network;
transmit a handover request message to the device if the priority of the device is higher than a priority of the coordinator based on the information received from the device;
receive a response to the handover request message from the device;
broadcast a first beacon on the low rate physical channel, the first beacon including identification information indicating that the device will be a new coordinator of the wireless network and number information indicating a number of beacons that the coordinator will broadcast before the handover occurs; and
broadcast one or more beacons, corresponding to the number indicated by the number information, on the low rate physical channel, each of the one or more beacons including updated number information indicating a number of remaining beacons that the coordinator will send before the handover occurs, wherein the updated number information included in a last beacon among the one or more beacons is set to “0.”
13. A device in a wireless network in which a high rate physical channel and a low rate physical channel are used for communication, the wireless network including a coordinator and at least one device, wherein the device is configured to:
transmit information associated with a priority of the device to the coordinator when the device joins the wireless network;
receive a handover request message from the coordinator if the priority of the device is higher than a priority of the coordinator based on the information transmitted to the coordinator;
transmit a response to the handover request message to the coordinator;
receive a first beacon on the low rate physical channel, the first beacon including identification information indicating that the device will be a new coordinator of the wireless network and number information indicating a number of beacons that the coordinator will broadcast before the handover occurs; and
receive one or more beacons broadcast by the coordinator on the low rate physical channel, a number of the one or more beacons corresponding to the number of beacons indicated by the number information, each of the one or more beacons including updated number information indicating a number of remaining beacons that the coordinator will send before the handover occurs, wherein the updated number information included in a last beacon among the one or more beacons is set to “0.”