Method and apparatus for reducing latency during wireless connectivity changes

• US 9,344,934 B2
• Filed: 06/19/2006
• Issued: 05/17/2016
• Est. Priority Date: 06/21/2005
• Status: Active Grant

• Current Assignee: Google Technology Holdings LLC (Alphabet Inc.)
• Original Assignee: Google Technology Holdings LLC (Alphabet Inc.)
• Inventors: Bedekar, Anand S., Agrawal, Rajeev, Gopikanth, Venkat, Kalyanasundaram, Suresh, Ram OV, Vishnu
• Primary Examiner(s): CASCA, FRED A
• Application Number:
  US11/913,936
• Publication Number:
  US 20080167037A1
• Time in Patent Office: 3,620 Days
• Field of Search: 455/435.1, 455/435.2, 455/436, 455/433, 455/445, 455/432.1, 455/517, 455/422.1, 455/453, 455/502, 370/338, 370/331, 709/230, 709/238, 709/223, 709/228, 709/232, 380/270
• US Class Current: 1/1
• CPC Class Codes: H04W 36/0016 Hand-off preparation specially adapted for end-to-end data sessions
• CPC Class Codes: H04W 36/005 involving radio access media independent information, e.g. MIH [Media independent Hand-off]
• CPC Class Codes: H04W 36/02 Buffering or recovering information during reselection ; Modification of the traffic flow during hand-off
• CPC Class Codes: H04W 60/00 Affiliation to network, e.g. registration; Terminating affiliation with the network, e.g. de-registration
• CPC Class Codes: H04W 60/005 Multiple registrations, e.g. multihoming
• CPC Class Codes: H04W 80/00 Wireless network protocols or protocol adaptations to wireless operation
• CPC Class Codes: H04W 80/04 Network layer protocols, e.g. mobile IP [Internet Protocol]
• CPC Class Codes: H04W 92/20 between access points

Abstract

A wireless access point (102) detects an indicia of a change in wireless connectivity of a mobile station (101) with respect to itself and another wireless access point (103). The wireless access point then automatically effects at least one of establishing a communication between itself and the second wireless access point regarding the change in wireless connectivity and/or establishing a temporary data tunnel as between itself and the second wireless access point. These network elements can also act to automatically establish a data flow path for the mobile station as between the second wireless access point and a network element (such as a mobility management agent (105)) that is external to the common subnet. In a preferred approach this comprises, at least in part, automatically sending a registration request to the network element other than in response to a specific request from the mobile station to send such a registration request.

Claims

1. A method for effecting a handover of a data flow for a mobile station from a first wireless access point to a second wireless access point, the method comprising:

detecting, by a processor, indicia of a change in wireless connectivity of the mobile station with respect to the first wireless access point and the second wireless access point, wherein the first wireless access point and the second wireless access point share a common subnet and wherein the change in wireless connectivity is associated with a handover of the data flow for the mobile station to the second wireless access point from the first wireless access point;

establishing a temporary data tunnel between the first and second wireless access point; and

automatically establishing a path for the data flow for the mobile station between the second wireless access point and a network element that is hierarchically differentiated from the second wireless access point, wherein automatically establishing comprises, at least in part, automatically sending a registration request from the second wireless access point to the network element other than in response to a specific request from the mobile station to send the registration request, wherein automatically sending the registration request from the second wireless access point to the network element comprises automatically sending, prior to completion of the change in wireless connectivity, the registration request from the second wireless access point to the network element in response to a specific message having been received by the second wireless access point as transmitted by the first wireless access point.

2. The method of claim 1 wherein detecting indicia of a change in wireless connectivity comprises detecting indicia of a change in wireless connectivity prior to completion of the change in wireless connectivity.

3. The method of claim 2 wherein automatically sending a registration request from the second wireless access point to the network element comprises automatically sending a registration request from the second wireless access point to the network element in response to a specific message having been received by the second wireless access point as transmitted by the first wireless access point.

4. The method of claim 3 wherein automatically sending a registration request from the second wireless access point to the network element further comprises automatically sending the registration request prior to completion of the change in wireless connectivity.

5. The method of claim 4 wherein automatically establishing a data flow path further comprises automatically establishing the data flow path prior to completion of the change in wireless connectivity.

6. The method of claim 2 wherein the establishing of a temporary data tunnel between the first and second wireless access point comprises automatically establishing a temporary data flow path between the first wireless access point and the second wireless access point in response to detection of the indicia of the change in wireless connectivity.

7. The method of claim 6 wherein automatically establishing a temporary data flow path further comprises transporting at least some data as transmitted by the network element and as intended for the mobile station from the first wireless access point to the second wireless access point using the temporary data flow path.

8. The method of claim 6 wherein automatically sending a registration request from the second wireless access point to the network element comprises automatically sending the registration request from the second wireless access point to the network element subsequent to completion of the change in wireless connectivity.

9. The method of claim 7 wherein automatically establishing a temporary data flow path further comprises buffering at least some of the data at the second wireless access point to provide buffered data.

10. The method of claim 9 wherein automatically establishing a temporary data flow path further comprises transmitting at least some of the buffered data to the mobile station subsequent to completion of the change in wireless connectivity.

11. The method of claim 9 wherein automatically establishing a temporary data flow path further comprises automatically discarding at least some of the data in response to detection of at least one predetermined discard criteria.

12. The method of claim 2 wherein:

establishment of a temporary data tunnel between the first and second wireless access point

comprises automatically establishing a temporary data flow path between the first wireless access point and the second wireless access point prior to completion of the change in wireless connectivity.

13. The method of claim 12 wherein automatically establishing a data flow path further comprises automatically initiating establishment of the data flow path prior to completion of the change in wireless connectivity.

14. The method of claim 1 wherein detecting indicia of a handover comprises detecting indicia of a handover subsequent to completion of the handover.

15. The method of claim 14 wherein automatically sending a registration request from the second wireless access point to the network element comprises automatically sending the registration request from the second wireless access point to the network element subsequent to completion of the change in wireless connectivity and in the absence of a specific registration request from the mobile station.

16. The method of claim 15 wherein the establishing of a temporary data tunnel between the first and second wireless access point further comprises transporting at least some data as transmitted by the network element and as intended for the mobile station from the first wireless access point to the second wireless access point using a temporary data flow path between the first wireless access point and the second wireless access point.

17. The method of claim 15 wherein transporting at least some data as transmitted by the network element and as intended for the mobile station from the first wireless access point to the second wireless access point using a temporary data flow path further comprises:

acquiring at the second wireless access point identifying information for the first wireless access point;

using the identifying information to facilitate establishing the temporary data flow path.

18. A wireless access point for use in a communication network comprising a local subnet that comprises a plurality of wireless access points, the wireless access point comprising:

a change in wireless connectivity detector responsive to indicia of a change in wireless connectivity of a mobile station with respect to another wireless access point, wherein the another wireless access point comprises a part of the local subnet and wherein the change in wireless connectivity is associated with a handover of a data flow for the mobile station to the wireless access point from the another wireless access point;

a data flow path establishment unit that is responsive to the change in wireless connectivity detector wherein the data flow path establishment unit is configured and arranged to;

establish a temporary data tunnel between the wireless access point and the another wireless access point; and

automatically establish a path for the data flow for the mobile station between the wireless access point and the another wireless access point;

a registration request module; and

a transmitter operably coupled to the registration request module and being configured and arranged to transmit, as part of the handover of the data flow to the wireless access point from the another wireless access point, a registration request to a network element that is external to the local subnet other than in response to a specific request from the mobile station to send the registration request, wherein transmitting the registration request to the network element comprises automatically transmitting, prior to completion of the change in wireless connectivity, the registration request to the network element in response to a specific message having been received by the wireless access point as transmitted by the another wireless access point.

19. The wireless access point of claim 18 wherein the change in wireless connectivity detector comprises means for at least one of:

detecting the change in wireless connectivity prior to completion of the change in wireless connectivity;

detecting the change in wireless connectivity subsequent to completion of the change in wireless connectivity.

20. The wireless access point of claim 18 wherein the transmitter comprises means for providing the registration request to the network element without specific instructions from the mobile station in this regard to facilitate establishing a data path between the network element and the mobile station via the wireless access point when the wireless access point receives the handed over mobile station whose wireless connectivity has changed.