Service apparatus, method of controlling switching of connection destination of client apparatus by service apparatus, and storage medium readable by machine

• US 8,014,355 B2
• Filed: 09/30/2005
• Issued: 09/06/2011
• Est. Priority Date: 03/31/2005
• Status: Active Grant

• Current Assignee: Fujitsu Client Computing Limited (Lenovo Group Ltd.)
• Original Assignee: Fujitsu Limited
• Inventors: Koga, Kifumi
• Primary Examiner(s): Yao; Kwang B
• Assistant Examiner(s): Bokhari; Syed M
• Application Number:
  US11/239,065
• Publication Number:
  US 20060251104A1
• Time in Patent Office: 2,167 Days
• Field of Search: 370/331, 370/321, 370/229, 370/314, 370/335, 370/352, 455/33, 455/426, 455/103, 455/436, 455/411, 375/132
• US Class Current: 370/331
• CPC Class Codes: H04W 48/20 Selecting an access point
• CPC Class Codes: H04W 74/004 in the uplink, i.e. towards network
• CPC Class Codes: H04W 84/12 WLAN [Wireless Local Area Networks]

Abstract

When a service apparatus detects a predetermined state, the service apparatus selects one of a plurality of client apparatuses connected to the service apparatus and selects a client apparatus to which a connection should be cut. The service apparatus determines another service apparatus to be a redirection destination of the client through communication with other service apparatuses which are capable of establishing a connection with the client. The service apparatus gives control information to the other service apparatuses and inhibits transmission of a response, which indicates that connection with the client is possible, corresponding to a probe request from the client apparatus for a given period of time.

Claims

1. A service apparatus providing a radio connection service to client apparatuses by returning a response in response to a probe request from an unconnected client apparatus to execute a radio connection procedure with the client apparatus, and by returning a response in response to a probe request from a connected client apparatus to continue a connected state with the client apparatus, the service apparatus comprising:

a selecting unit to select a client apparatus to which connection should be disconnected when a predetermined state is detected;

a requesting unit to request other service apparatuses connected through a network to return a response, which indicates that connection is possible, in response to a probe request from the selected client apparatus; and

a unit to receive the probe request from the selected client apparatus and to inhibit transmission of the response that indicates that continuing the connected state with the selected client apparatus is possible, in answer to the probe request from the service apparatus to the selected client apparatus for a given period of time to disconnect the connection with the selected client apparatus.

2. The service apparatus according to claim 1, wherein the requesting unit includes:

a unit to transmit an inquiry to inquire states of the other service apparatuses;

a receiving unit to receive, from the other service apparatuses responding to the inquiry, replies that include state information indicating the states of the other service apparatuses through a network;

a determining unit to determine, as a new connection destination of the selected client apparatus, one of the other service apparatuses as transmission sources of the replies based on the state information included in the received replies; and

a unit to transmit to the other service apparatuses, through a network, control information for the determined one of the other service apparatuses to respond to the probe request from the selected client apparatus and the other service apparatuses other than the determined one of the other service apparatuses to inhibit transmission of the response, which indicates that connection is possible, corresponding to the probe request from the selected client apparatus, for the given period of time, the control information including identification information of the determined one of the other service apparatuses and identification information of the selected client apparatus.

3. The service apparatus according to claim 2, wherein the state information includes intensities of reception signals from the selected client apparatus in the other service apparatuses, and

the determining unit determines the one of the other service apparatuses with the best reception signal intensity as a connection destination of the client apparatus.

4. The service apparatus according to claim 3, wherein the state information further includes information indicating processing loads in the other service apparatuses, and the determining unit determines the one of the other service apparatuses to be a connection destination of the client apparatus, based on the reception signal intensities and the processing loads.

5. The service apparatus according to claim 2, further comprising:

a unit to inhibit, when the identification information of the service apparatus included in the control information received from the other service apparatuses does not coincide with identification information of the own service apparatus, the transmission of the response which indicates that connection is possible corresponding to the probe request from the selected client apparatus for the predetermined period.

6. The service apparatus according to claim 2, further comprising:

a unit to judge whether a client apparatus as a transmission source of the probe request is unconnected to the own service apparatus; and

a unit to judge, when the client apparatus is unconnected, whether it is possible to connect the client apparatus to the own service apparatus, wherein when the client apparatus cannot be connected, the inquiry is executed on the other service apparatuses.

7. The service apparatus according to claim 1, wherein the selecting unit selects a client apparatus with a lowest reception signal intensity from plural client apparatuses connected to the own service apparatus.

8. The service apparatus according to claim 1, wherein the selecting unit executing the selection of the client apparatus, when it is detected that a load on the own service apparatus is equal to or larger than a predetermined value.

9. The service apparatus according to claim 1, wherein the selecting unit executing the selection of the client apparatus, when it is detected that the number of client apparatuses to be connected to the own service apparatus is equal to or larger than a predetermined value.

10. A method of controlling switching of a connection destination of a client apparatus by a service apparatus included in a group of service apparatuses providing a radio connection service to client apparatuses by returning a response in response to a probe request from an unconnected client apparatus to execute a radio connection procedure with the client apparatus, and by returning a response in response to a probe request from a connected client apparatus to continue a connected state with the client apparatus,

selecting a client apparatus to which connection should be disconnected when a predetermined state is detected,

requesting other service apparatuses connected through a network to return a response, which indicates that connection is possible, in response to a probe request from the selected client apparatus;

receiving the probe request from the selected client apparatus; and

inhibiting transmission of the response that indicates that continuing the connected state with the selected client apparatus is possible, in answer to the probe request from the service apparatus to the selected client apparatus for a given period of time to disconnect the connection with the selected client apparatus.

11. A non-transitory storage medium readable by a service apparatus, storing a program for causing the service apparatus included in a group of service apparatuses providing a radio connection service to client apparatuses by returning a response in response to a probe request from an unconnected client apparatus to execute a radio connection procedure with the client apparatus, and by returning a response in response to a probe request from a connected client apparatus to continue a connected state with the client apparatus, to perform control for switching a connection destination of the client apparatus,

the program causing the service apparatus to perform:

selecting a client apparatus to which connection should be disconnected when a predetermined state is detected,

requesting other service apparatuses connected through a network to return a response, which indicates that connection is possible, corresponding to the probe request from the selected client apparatus,

receiving the probe request from the selected client apparatus; and

inhibiting transmission of the response that indicates that continuing the connected state with the selected client apparatus is possible, in answer to the probe request from the service apparatus to the selected client apparatus for a given period of time to disconnect the connection with the selected client apparatus.