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

• US 20060251104A1
• Filed: 09/30/2005
• Published: 11/09/2006
• 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
• Granted Patent: US 8,014,355 B2
• Time in Patent Office: Days
• US Class Current: 370/449
• 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

To decentralize concentration of clients of a wireless LAN to a service apparatus of the wireless LAN. When a service apparatus detects a predetermined state, the service apparatus selects one of plural client apparatuses connected to the own apparatus and selects a client apparatus to which connection should be cut when the predetermined state is detected. 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 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. On the other hand, the determined another service apparatus responds to the probe request and the other services apparatuses inhibit transmission of a response, which indicates that connection with the client is possible, for a given period of time in response to the probe request.

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

a requesting unit 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; and

a unit inhibiting transmission of the response, which indicates that connection is possible, corresponding to the probe request from the selected client, for a given period of time, after the connection with the selected client apparatus is disconnected.

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

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

a receiving unit receiving, 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 determining, 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 transmitting 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. A 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. A 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. A service apparatus according to claim 2, further comprising:

a unit inhibiting, 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. A service apparatus according to claim 2, further comprising:

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

a unit judging, 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. A 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. A 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. A 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, wherein

the service apparatus

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

requests 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

inhibits transmission of the response, which indicates that connection is possible, corresponding to the probe request from the selected client, for a given period of time, after the connection with the selected client apparatus is disconnected.

11. A storage medium readable by a machine, storing a program for

causing 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, to perform control for switching a connection destination of the client apparatus,

the program comprising steps of:

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, and

inhibiting transmission of the response, which indicates that connection is possible, corresponding to a probe request from the selected client, for a given period of time, after the connection with the selected client apparatus is disconnected.