REDUCING DATA LOSS DURING HANDOFFS IN WIRELESS COMMUNICATION

• US 20070091848A1
• Filed: 10/02/2006
• Published: 04/26/2007
• Est. Priority Date: 10/03/2005
• Status: Abandoned Application

• Current Assignee: Divitas Networks, Inc.
• Original Assignee: Divitas Networks, Inc.
• Inventors: Rao, Prasad, Mittal, Ajay, Marder, Josh, Karia, Snehal, Solsona-Palomar, Marc, Palakkal, Rajesh, Athuluru, Srinivasa, Wang, Derek, Seshadri, Varad
• Application Number:
  US11/537,980
• Publication Number:
  US 20070091848A1
• Time in Patent Office: Days
• US Class Current: 370/331
• CPC Class Codes: H04L 61/2564 for a higher-layer protocol, e.g. for session initiation protocol [SIP]
• CPC Class Codes: H04L 61/2575 using address mapping retrieval, e.g. simple traversal of user datagram protocol through session traversal utilities for NAT [STUN]
• CPC Class Codes: H04L 61/2578 without involvement of the NAT server
• CPC Class Codes: H04L 63/029 Firewall traversal, e.g. tunnelling or, creating pinholes
• CPC Class Codes: H04L 63/20 for managing network security; network security policies in general filtering policies H04L63/0227
• CPC Class Codes: H04L 65/1069 Session establishment or de-establishment
• CPC Class Codes: H04L 65/1083 In-session procedures
• CPC Class Codes: H04L 65/1095 Inter-network session transfer or sharing
• CPC Class Codes: H04L 65/1101 Session protocols
• CPC Class Codes: H04L 65/401 wherein the services involve a main real-time session and one or more additional parallel real-time or time sensitive sessions, e.g. white board sharing or spawning of a subconference
• CPC Class Codes: H04L 65/403 Arrangements for multi-party communication, e.g. for conferences data switching systems for conference H04L12/18; arrangements for connecting several subscribers to a common circuit, i.e. affording conference facilities H04M3/56; television conferencing systems H04N7/15
• CPC Class Codes: H04L 65/70 Media network packetisation
• CPC Class Codes: H04L 69/16 Implementation or adaptation of Internet protocol [IP], of transmission control protocol [TCP] or of user datagram protocol [UDP]
• CPC Class Codes: H04L 69/164 Adaptation or special uses of UDP protocol
• CPC Class Codes: H04L 69/22 Parsing or analysis of headers
• CPC Class Codes: H04W 36/02 Buffering or recovering information during reselection ; Modification of the traffic flow during hand-off
• CPC Class Codes: H04W 36/08 Reselecting an access point
• CPC Class Codes: H04W 36/38 by fixed network equipment
• CPC Class Codes: H04W 4/16 Communication-related supplementary services, e.g. call-transfer or call-hold
• CPC Class Codes: H04W 8/02 Processing of mobility data, e.g. registration information at HLR [Home Location Register] or VLR [Visitor Location Register]; Transfer of mobility data, e.g. between HLR, VLR or external networks
• CPC Class Codes: H04W 8/04 : Registration at HLR or HSS [Home Subscriber Server]
• CPC Class Codes: H04W 8/08 : Mobility data transfer
• CPC Class Codes: H04W 80/04 : Network layer protocols, e.g. mobile IP [Internet Protocol]
• CPC Class Codes: H04W 92/02 : Inter-networking arrangements

Abstract

A method for reducing data loss when a client device performs a handoff from a first radio station to a second radio station. The method includes detecting imminence of the handoff using one or more criteria. The method also includes buffering incoming data upon the imminence of the handoff to generate buffered incoming data, the incoming data being addressed to the client device. The method further includes transmitting the buffered incoming data to the client device through the second radio station if the handoff is completed and if the buffered incoming data is not discarded.

Claims

1. A method for reducing data loss when a client device performs a handoff from a first radio station to a second radio station, the method comprising:

detecting imminence of the handoff using one or more criteria;

buffering incoming data upon the imminence of the handoff to generate buffered incoming data, the incoming data being addressed to the client device; and

transmitting the buffered incoming data to the client device through the second radio station if the handoff is completed and if the buffered incoming data is not discarded.

2. The method of claim 1 wherein the one or more criteria pertain to at least one of signal strength, channel loading, and communication quality.

3. The method of claim 1 further comprising:

measuring a time duration of the buffering the incoming data; and

discarding the buffered incoming data if the time duration reaches an incoming-data buffering duration threshold.

4. The method of claim 1 further comprising:

monitoring the size of the buffered incoming data; and

discarding the buffered incoming data if the size of the buffered incoming data reaches an incoming-data buffering size threshold.

5. The method of claim 1 further comprising:

measuring a time duration before the client device registers information pertaining to the second radio station with an authentication mechanism; and

rejecting connection between the client device and the second radio station if the client device fails to register the information pertaining to the second radio station within an authentication duration threshold.

6. The method of claim 5 wherein the information pertaining to the second radio station includes an IP address provided by the second radio station.

7. The method of claim 1 further comprising buffering outgoing data upon the imminence of the handoff to generate buffered outgoing data, the outgoing data being originated from the client device, the buffering the outgoing data being performed by at least one of the client device and a device connected with the client device.

8. The method of claim 7 further comprising:

measuring a time duration of the buffering the outgoing data; and

discarding the buffered outgoing data if the time duration reaches an outgoing-data buffering duration threshold.

9. The method of claim 7 further comprising:

monitoring the size of the buffered outgoing data; and

discarding the buffered outgoing data if the size of the buffered outgoing data reaches an outgoing-data buffering size threshold.

10. The method of claim 7 further comprising transmitting the buffered outgoing data through the second radio station if the handoff is completed and if the buffered outgoing data is not discarded.

11. The method of claim 1 wherein at least one of the first radio station and the second radio station represents at least one of a wireless access point of a wireless network and a base transceiver station of a cellular network.

12. The method of claim 1 wherein the first radio station and the second radio station are implemented based on different communication standards.

13. A system for reducing data loss when a client device performs a handoff from a first radio station to a second radio station, the system comprising:

a detecting mechanism configured to determine imminence of the handoff; and

a server buffer configured to buffer incoming data to generate buffered incoming data upon the imminence of the handoff, the incoming data being addressed to the client device,

wherein the buffered incoming data is to be transmitted to the client device through the second radio station if the handoff is completed and if the buffered incoming data is not discarded.

14. The system of claim 13 wherein the detecting mechanism is implemented in at least one of the client device and a server and is configured to determine the imminence of the handoff based on one or more criteria pertaining to at least one of signal strength, channel loading, and communication quality.

15. The system of claim 13 further comprising:

a server buffering timer configured to measure a time duration that the incoming data is buffered; and

a deleting mechanism configured to delete the buffered incoming data from the server buffer if the time duration reaches an incoming-data buffering duration threshold.

16. The system of claim 13 further comprising:

a counter configured to monitor the size of the buffered incoming data; and

a deleting mechanism configured to delete the buffered incoming data from the server buffer if the size of the buffered incoming data reaches an incoming-data buffering size threshold.

17. The system of claim 13 further comprising:

an authentication timer configured to measure a time duration before the client device registers information pertaining to the second radio station; and

an authentication mechanism configured to store an authentication duration threshold and to reject connection between the client device and the second radio station if the client device fails to register the information pertaining to the second radio station with the authentication mechanism within the authentication duration threshold.

18. The system of claim 17 wherein the information pertaining to the second radio station includes an IP address provided by the second radio station.

19. The system of claim 13 further comprising a client buffer configured to buffer outgoing data upon the imminence of the handoff to generate buffered outgoing data, the outgoing data being originated from the client device, the client buffer being implemented in at least one of the client device and a device connected with the client device.

20. The system of claim 19 further comprising:

a client buffering timer configured to measure a time duration that the outgoing data is buffered; and

a deleting mechanism configured to delete the buffered outgoing data from the client buffer if the time duration reaches an outgoing-data buffering duration threshold.

21. The system of claim 19 further comprising:

a counter configured to monitor the size of the buffered outgoing data; and

a deleting mechanism configured to delete the buffered outgoing data from the client buffer if the size of the buffered outgoing data reaches an outgoing-data buffering size threshold.

22. The system of claim 19 wherein the buffered outgoing data is to be transmitted through the second radio station if the handoff is completed and if the buffered outgoing data is not discarded.

23. The system of claim 13 wherein at least one of the first radio station and the second radio station represents at least one of a wireless access point of a wireless network and a base transceiver station of a cellular network.

24. The system of claim 13 wherein the first radio station and the second radio station are implemented based on different communication standards.