Wireless personal area network with automatic detachment

• US 6,314,091 B1
• Filed: 07/02/1998
• Issued: 11/06/2001
• Est. Priority Date: 07/02/1998
• Status: Expired due to Term

• Current Assignee: Raytheon BBN Technlogies Corp. (Rtx Corporation), Verizon Corporate Services Group Incorporated (Verizon Communications Inc.)
• Original Assignee: GTE Service Corporation (Verizon Communications Inc.)
• Inventors: Brand, Thomas, LaRowe, Richard P. Jr., Wacker, David
• Primary Examiner(s): NGO, RICKY QUOC
• Application Number:
  US09/109,438
• Time in Patent Office: 1,223 Days
• Field of Search: 370/338, 370/401, 370/230, 370/475, 370/235, 370/311, 370/313, 370/328, 370/329, 370/331, 455/556, 455/557, 709/223, 709/227, 709/237
• US Class Current: 370/338
• CPC Class Codes: H04W 76/38 triggered by timers
• CPC Class Codes: H04W 84/12 WLAN [Wireless Local Area Networks]

Abstract

A personal area network includes a plurality of peripheral devices attached to the network, at least one attaching peripheral device requesting to attach to the network, and a hub device connected to the network and communicating with the plurality of peripheral devices. The hub device receives the attachment request from the attaching peripheral device, provides the attaching peripheral device with attachment approval and a time-out interval, and detaches the attaching peripheral device when the attaching peripheral device fails to communicate with the hub device for a period of time equal to the time-out interval.

Claims

1. A network comprising:

a plurality of peripheral devices;

a hub device communicating with the peripheral devices; and

at least one attaching peripheral device requesting to communicate with the hub device, the hub device receiving the communication request from the attaching peripheral device, providing the attaching peripheral device with approval and a time-out interval, and detaching the attaching peripheral device when the attaching peripheral device fails to communicate with the hub device for a period of time equal to the time-out interval.

2. The network of claim 1, wherein the hub device includes:

a register with an entry for each of the peripheral devices, each of the entries storing an indication of whether the corresponding peripheral device has communicated with the hub device.

3. The network of claim 2, wherein the hub device further includes:

a timer that counts a period of time equal to the time-out interval and outputs signals indicative of a start and finish of the counting, and

a read/write unit, connected to the timer and the register, that receives the start signal from the timer and resets the entries in the register, that sets the entries in the register when the hub device receives communication from the corresponding peripheral devices, and that receives the finish signal from the timer and determines which of the peripheral devices has failed to communicate with the hub device during the time-out interval by reference to the entries in the register.

4. The network of claim 3, wherein the hub device further includes:

a detach unit that detaches from the network the peripheral devices that have failed to communicate with the hub device during the time-out interval.

5. The network of claim 1, wherein the hub device includes:

hub digital control logic that determines whether to permit the attaching peripheral device to communicate with the hub device in response to the communication request, selects an address for the attaching peripheral device, and transmits a message to the attaching peripheral device including the selected address, an indication of whether the attaching peripheral device is permitted to communicate with the hub device, and the time-out interval.

6. The network of claim 5, wherein the attaching peripheral device includes:

peripheral digital control logic that receives the message from the hub device, records the selected address, and sets a detach interval corresponding to the time-out interval.

7. The network of claim 6, wherein the peripheral digital control logic includes:

means for setting the detach interval to a value less than the time-out interval.

8. The network of claim 1, wherein the attaching peripheral device includes:

means for negotiating with the hub device to determine the time-out interval.

9. The network of claim 1, wherein the time-out interval is an indefinite period.

10. In a personal area network having a plurality of peripheral devices attached to the network, at least one attaching peripheral device unattached from the network, and a hub device connected to the network, a method for attaching and detaching the attaching peripheral device comprising:

transmitting, by the attaching peripheral device, a request to attach to the network;

receiving the attachment request at the hub device;

selecting an address for the attaching peripheral device;

providing the attaching peripheral device with attachment approval, the selected address, and a time-out interval;

failing to receive communication at the hub device from the attaching peripheral device for a period of time equal to the time-out interval; and

detaching the attaching peripheral device in response to the failure to receive communication from the attaching peripheral device for the time period.

11. The method of claim 10, wherein the step of failing to receive communication includes the substep of:

storing, in a register in the hub device, an entry for each of the attached peripheral devices indicating whether the corresponding attached peripheral device has communicated with the hub device.

12. The method of claim 11, wherein the step of failing to receive communication further includes the substeps of:

counting the time period,

outputting signals indicative of a start and finish of the counting,

resetting the entries in the register in response to the start signal,

setting the entries in the register when the hub device receives communication from the corresponding attached peripheral devices, and

determining, in response to the finish signal, which of the attached peripheral devices has failed to communicate with the hub device during the time-out interval by reference to the entries in the register.

13. The method of claim 10, wherein the step of providing the attaching peripheral device with attachment approval includes the substeps of:

determining, at the hub device, whether to permit the attaching peripheral device to attach to the network in response to the attachment request, and

transmitting a message to the attaching peripheral device including the selected address, an indication of whether the attaching peripheral device is permitted to attach to the network, and the time-out interval.

14. The method of claim 13, further comprising the steps of:

receiving, at the attaching peripheral device, the message from the hub device,

recording the selected address in the attaching peripheral device, and

setting a detach interval in the attaching peripheral device corresponding to the time-out interval.

15. The method of claim 14, wherein the step of setting a detach interval includes the substep of:

setting the detach interval to a value less than the time-out interval.

16. The method of claim 10, wherein the step of providing the attaching peripheral device with attachment approval includes the substep of:

negotiating between the hub device and the attaching peripheral device to determine the time-out interval.

17. In a network having a plurality of peripheral devices connected to a hub device, the hub device comprising:

a register with an entry for each of the peripheral devices, each of the entries storing an indication of whether the corresponding peripheral device has communicated with the hub device;

a timer that counts a period of time equal to a time-out interval and outputs signals indicative of a start and finish of the counting;

a read/write unit, connected to the timer and the register, that receives the start signal from the timer and resets the entries in the register, that sets the entries in the register when the hub device receives communication from the corresponding peripheral devices, and that receives the finish signal from the timer and determines which of the peripheral devices has failed to communicate with the hub device during the time-out interval by reference to the entries in the register; and

a detach unit that detaches from the network the peripheral devices that have failed to communicate with the hub device during the time-out interval.

18. The hub device of claim 17, further comprising:

means for receiving a request from an attaching peripheral device to connect to the network; and

means for providing the attaching peripheral device with attachment approval and the time-out interval.

19. The hub device of claim 18, wherein the means for providing the attaching peripheral device with attachment approval includes:

means for determining whether to permit the attaching peripheral device to connect to the network in response to the attachment request,

means for selecting an address for the attaching peripheral device, and

means for transmitting a message to the attaching peripheral device including the selected address, an indication of whether the attaching peripheral device is permitted to connect to the network, and the time-out interval.

20. The hub device of claim 18, wherein the means for providing the attaching peripheral device with attachment approval includes:

means for negotiating with the attaching peripheral device to determine the time-out interval.

21. In a network having a plurality of peripheral devices and a hub device, each of the peripheral devices comprising:

a register having a single entry that stores an indication of whether the peripheral device has communicated with the hub device;

a timer that counts a period of time equal to a detach interval and outputs signals indicative of a start and finish of the counting;

a read/write unit, connected to the timer and the register, that receives the start signal from the timer and resets the register entry, that sets the register entry when the peripheral device communicates with the hub device, and that receives the finish signal from the timer and determines whether the peripheral device failed to communicate with the hub device during the detach interval by reference to the register entry; and

a detach unit that prepares the peripheral device for detaching from the network when the peripheral device fails to communicate with the hub device during the detach interval.

22. The peripheral device of claim 21, further comprising:

means for transmitting to the hub device a request to attach to the network.

23. The peripheral device of claim 22, further comprising:

means for receiving attachment approval and a time-out interval from the hub device; and

means for setting the detach interval based on the time-out interval.

24. The peripheral device of claim 23, wherein the means for receiving attachment approval includes:

means for negotiating with the hub device to determine the time-out interval.

25. The peripheral device of claim 23, wherein the means for setting the detach interval includes:

means for assigning a value to the detach interval that is less than the time-out interval received from the hub device.

26. A wireless network, comprising:

a plurality of peripheral devices; and

a hub device communicating with the peripheral devices, the hub device including

means for counting for a predetermined period of time,

means for storing data for each of the peripheral devices in response to a start of the counting,

means for changing the data for each of the peripheral devices that has communicated with the hub device during the predetermined time period,

means for determining which of the peripheral devices failed to communicate with the hub device during the predetermined time period based on the changed data, and

means for disconnecting, from the network, the peripheral devices that have failed to communicate with the hub device during the predetermined time period.

27. In a wireless network having a plurality of peripheral devices and a hub device communicating with the peripheral devices, a method, executed by the hub device, comprising the steps of:

counting for a predetermined period of time;

storing first data for each of the peripheral devices in response to a start of the counting;

storing second data for each of the peripheral devices that has communicated with the hub device during the predetermined time period;

determining which of the peripheral devices failed to communicate with the hub device during the predetermined time period based on the second data; and

disconnecting, from the network, the peripheral devices that have failed to communicate with the hub device during the predetermined time period.