Timer-Based Mobile IP Re-Registration for Wireless Handoff

Solution Overview

Problem

Wireless devices experience excessive handoffs between access points in a wireless wide area network, leading to frequent Mobile IP re-registrations that consume network resources and battery power, particularly when located at boundaries between areas served by different access points with equal signal strengths, causing oscillation and unnecessary re-registrations.

Innovation Solution

Implementing a timer-based re-registration method where a wireless device receives an identifier and a timer value from an access point, delaying subsequent Mobile IP re-registrations with other network access servers until the timer expires, thereby reducing unnecessary re-registrations during back-and-forth handoffs between access points.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a wireless device performs Mobile IP re-registration every time it hands off between access points, then the device maintains accurate location registration, but network resources and battery power are excessively consumed

Engineering Contradiction:

Improvelocation registration accuracyVSAvoidbattery power consumption

Core Design Contradiction:

ReliabilityVSLoss of energy

Solution Approach 1:

The system performs a preliminary check by comparing the new access point's network access server identifier with the currently registered identifier before executing re-registration. This preliminary comparison action prevents unnecessary re-registration operations when the device is in an oscillation state, thereby conserving battery power while maintaining registration accuracy when actually needed.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The system implements a feedback mechanism where the wireless device continuously monitors access point identifiers and handoff events, using this feedback information to intelligently determine whether re-registration is necessary. This feedback-based decision-making prevents energy-wasting re-registrations during oscillation while ensuring accurate location tracking when the device has genuinely moved to a different network access server.

Inventive Principle:

Principle #23Feedback

2Reliability

If a wireless device performs Mobile IP re-registration every time it hands off between access points, then the device maintains accurate location registration, but network resources are excessively consumed

Engineering Contradiction:

Improvelocation registration accuracyVSAvoidnetwork resource consumption

Core Design Contradiction:

ReliabilityVSQuantity of substance

Solution Approach 1:

The system performs a preliminary check by comparing the new access point's network access server identifier with the currently registered identifier before executing re-registration. This preliminary comparison action prevents unnecessary re-registration operations when the device is in an oscillation state, thereby conserving network resources while maintaining registration accuracy when actually needed.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The system implements a feedback mechanism where the wireless device continuously monitors access point identifiers and handoff events, using this feedback information to intelligently determine whether re-registration is necessary. This feedback-based decision-making prevents energy-wasting re-registrations during oscillation while ensuring accurate location tracking when the device has genuinely moved to a different network access server.

Inventive Principle:

Principle #23Feedback

3Reliability

If a wireless device located at a boundary between access points performs re-registration during signal oscillation, then the device maintains connection, but unnecessary re-registrations occur due to equal signal strengths

Engineering Contradiction:

Improveconnection continuityVSAvoidhandoff efficiency

Core Design Contradiction:

ReliabilityVSProductivity

Solution Approach 1:

The system performs a preliminary check by comparing the new access point's network access server identifier with the currently registered identifier before executing re-registration. This preliminary comparison action prevents unnecessary re-registration operations when the device is in an oscillation state, thereby conserving network resources while maintaining registration accuracy when actually needed.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The system implements a feedback mechanism where the wireless device continuously monitors access point identifiers and handoff events, using this feedback information to intelligently determine whether re-registration is necessary. This feedback-based decision-making prevents energy-wasting re-registrations during oscillation while ensuring accurate location tracking when the device has genuinely moved to a different network access server.

Inventive Principle:

Principle #23Feedback

Data Source

PatentUS7697489B1Method and system for timer-based mobile IP re-registration in a wireless wide area network

Publication Date: 2010.04.13 SPRINT SPECTRUM LP

AI summary

A network access server, such as a PDSN, might provide Mobile IP services to one or more access points for a wireless wide area network. A wireless device might handoff to an access point served by the network access server, and the wireless device might receive from the access point an identifier, such as a Packet Zone ID, that identifies the network access server. The wireless device might then register with the access server but delay making any subsequent Mobile IP re-registrations until after a predetermined amount of time.