Mobile Station Mobility Key Derivation and Route Optimization

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Solution Overview

Problem

Existing techniques for facilitating mobility in mobile stations are not efficient, particularly in situations where communication sessions need to be maintained across different networks, leading to suboptimal authentication and key management processes.

Innovation Solution

A mobility key is derived from a master key generated at an authentication server, which is used for authenticating mobility signaling in communication sessions, and a route optimization method is implemented to bypass the home agent, enhancing communication efficiency.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If traditional authentication and key management techniques are used for mobile station mobility, then security procedures can be established, but the process becomes inefficient and complex when mobile stations move between different communication networks

Engineering Contradiction:
Improvemobility management efficiencyVSAvoidauthentication and key management complexity
Core Design Contradiction:
ProductivityVSDevice complexity

Solution Approach 1:

The patent segments the authentication and key management process into distinct phases: initial authentication phase (establishing master key) and mobility phase (deriving mobility keys). This segmentation allows efficient handling of mobility events by reusing the initial authentication results rather than repeating full authentication procedures.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The patent performs preliminary authentication and master key establishment before mobility events occur. The home authentication server pre-establishes the master key, which can then be quickly derived into mobility keys when needed, avoiding the complexity of real-time authentication during mobility events.

Inventive Principle:
Principle #10Preliminary action

2Productivity

If home agent routing is used for mobile IP communication, then mobility support is provided, but communication routes are suboptimal and efficiency is reduced

Engineering Contradiction:
Improvecommunication efficiencyVSAvoidrouting delay
Core Design Contradiction:
ProductivityVSLoss of time

Solution Approach 1:

The patent implements dynamic route optimization by allowing the mobile station to directly communicate with the home authentication server and correspondent nodes when possible, rather than forcing all traffic through the home agent. The system dynamically selects between home agent routing and direct routing based on current network conditions and mobility state.

Inventive Principle:
Principle #15Dynamics

3Productivity

If mobility keys are not readily available, then security may be maintained, but authentication processes become slower and less efficient

Engineering Contradiction:
Improveauthentication speedVSAvoidkey availability
Core Design Contradiction:
ProductivityVSReliability

Solution Approach 1:

The patent changes the parameter of key derivation by introducing a deterministic algorithm that generates mobility keys from the master key using specific inputs (such as visitor network identifier and sequence numbers). This ensures that the same inputs always produce the same mobility key, providing both rapid generation and reliable reproduction of keys.

Inventive Principle:
Principle #35Parameter changes

Data Source

PatentEP1899839B1Method and devices for facilitating mobility for a mobile station
Publication Date: 2019.01.09 CISCO TECHNOLOGY INC
  • EP1899839B1 patent drawingFigure 1
  • EP1899839B1 patent drawingFigure 2
  • EP1899839B1 patent drawingFigure 3

AI summary

Providing a mobility key for a communication session for a mobile station includes facilitating initiation of the communication session. A master key for the communication session is established, where the master key is generated at an authentication server in response to authenticating the mobile station. A mobility key is derived from the authentication key at an access node, where the mobility key is operable to authenticate mobility signaling for the communication session.