Method and apparatus for reducing successive pre-registration attempts by access terminals

• US 9,883,477 B2
• Filed: 06/22/2015
• Issued: 01/30/2018
• Est. Priority Date: 09/23/2008
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Ramachandran, Shyamal, Klingenbrunn, Thomas, Balasubramanian, Srinivasan, Swaminathan, Arvind
• Primary Examiner(s): Pham, Chi H
• Assistant Examiner(s): Agureyev, Vladislav
• Application Number:
  US14/746,218
• Publication Number:
  US 20150296472A1
• Time in Patent Office: 953 Days
• Field of Search: None
• CPC Class Codes: H04W 36/0005 Control or signalling for completing the 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 60/04 using triggered events

Abstract

An access terminal pre-registers with a second access network via a first access network to ensure a quick handover in the future. Frequent pre-registration attempts are avoided by implementing a hysteresis timer that restricts when a pre-registration process can be initiated. The hysteresis timer is started when pre-registration is initiated by the access terminal. No new pre-registration attempts are permitted if the hysteresis timer has not expired. An abort condition can cause the hysteresis timer to be aborted early, and a new pre-registration can be initiated. Access points in the first access network may be grouped into one or more pre-registration zones. If the access terminal moves from a first access point to a second access point, a new pre-registration is skipped if the first and second access points have the same pre-registration zone or the second access point is aware of the pre-registration zone for the first access point.

Claims

1. A method operational in an access point of a first access network, comprising:

obtaining a pre-registration indicator from the first access network, wherein the pre-registration indicator indicates whether the first access network allows pre-registration with a second access network via the first access network;

obtaining a first pre-registration zone identifier, where the first pre-registration zone identifier identifies a group of access points within the first access network;

obtaining a secondary pre-registration zone list that includes zone identifiers associated with the first pre-registration zone identifier; and

advertising the pre-registration indicator, the first pre-registration zone identifier, and the secondary pre-registration zone list to one or more access terminals in a cell covered by the access point.

2. The method of claim 1, further comprising:

receiving a pre-registration request for the second access network from an access terminal operating within a cell covered by the access point; and

routing the pre-registration request to the second access network if the pre-registration indicator indicates that such pre-registration is allowed.

3. The method of claim 1, wherein the first pre-registration zone identifier and the secondary pre-registration zone list is utilized by receiving access terminals in a cell covered by the access point to determine whether a new pre-registration is needed with a second access network via the access point of the first access network.

4. An access point, comprising:

a wireless network interface to communicate with access terminals in a cell within a first access network;

a network interface to communicate with a second access network; and

a processing circuit coupled to the wireless network interface and the network interface, the processing circuit adapted to;

obtain a pre-registration indicator from the first access network, wherein the pre-registration indicator indicates whether the first access network allows pre-registration with a second access network via the first access network;

obtain a first pre-registration zone identifier, where the pre-registration zone identifier identifies a group of access points within the first access network;

obtain a secondary pre-registration zone list that includes zone identifiers associated with the first pre-registration zone identifier; and

advertise the pre-registration indicator, the first pre-registration zone identifier, and the secondary pre-registration zone list to one or more access terminals in a cell covered by the access point.

5. The access point of claim 4, wherein the processing circuit is further adapted to:

receive a pre-registration request for the second access network from an access terminal operating within a cell covered by the access point; and

route the pre-registration request to the second access network if the pre-registration indicator indicates that such pre-registration is allowed.

6. A method operational in a network server of a first access network, comprising:

generating a pre-registration indicator based on whether the first access network allows access terminals to pre-register with a second access network via the first access network;

grouping a plurality of cells in a first access network into one or more cell groups;

associating a first cell group with a first pre-registration zone;

generating a secondary zone list for the first pre-registration zone, where the secondary zone list excludes the first pre-registration zone; and

distributing the pre-registration indicator, the first pre-registration zone and the secondary zone list to access points within the cells for the first cell group.

7. The method of claim 6, wherein the first pre-registration zone and the secondary zone list is utilized by receiving access terminals to determine whether a new pre-registration is needed with a second access network via the first access network.

8. A method for deploying access points and pre-registration zones within a first access network, comprising:

advertising a first pre-registration zone identifier from a first group of access points;

advertising a second pre-registration zone identifier from a second group of access points;

deploying a third group of access points to form a boundary zone between the first group of access points and the second group of access points;

advertising a third pre-registration zone identifier from the third group of access points; and

advertising the first pre-registration zone identifier and second pre-registration zone identifier in a secondary pre-registration zone list from the third group of access points.

9. The method of claim 8, wherein the secondary pre-registration zone list excludes the third pre-registration zone identifier.

10. The method of claim 8, further comprising:

assigning the first pre-registration zone identifier to the first group of access points;

assigning the second pre-registration zone identifier to the second group of access points; and

assigning the third pre-registration zone identifier to the third group of access points.

11. The method of claim 8, wherein the first pre-registration zone identifier, second pre-registration zone identifier, and the third pre-registration zone identifier are the same zone identifier.