Smart Card Chip Personalization via Master Key Segmentation

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Solution Overview

Problem

Existing methods for personalizing security elements in mobile terminal devices, such as smart card chips, face challenges in securely pre-personalizing chips in an insecure environment without transmitting personal data to the manufacturer, and require significant administrative effort from both network operators and chip manufacturers.

Innovation Solution

A method that involves pre-personalizing the security element during production by determining a unique master key, which is then transmitted to a trust center, and finalizing personalization when the device is used for the first time by linking the user's personal data with the master key to personalize the security element, eliminating the need for conventional methods that require secure production sites and reducing administrative burdens.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of manufacture

If personalization data is transmitted to the chip manufacturer during pre-personalization, then the personalization process can be completed, but security is compromised because personal data is handled in an insecure environment

Engineering Contradiction:
Improvepersonalization processVSAvoidsecurity
Core Design Contradiction:
Ease of manufactureVSReliability

Solution Approach 1:

The personalization data is segmented into two parts: a first part is transmitted to the chip manufacturer during pre-personalization, while a second part remains at the network operator. This segmentation allows pre-personalization to proceed without compromising security, as the complete personalization data never resides in the insecure manufacturing environment.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The chip acts as an intermediary that receives the first part of personalization data during manufacturing and later combines it with the second part provided by the user during final personalization. This intermediary role enables the chip to facilitate personalization without requiring the manufacturer to handle complete personalization data.

Inventive Principle:
Principle #24Intermediary (Mediator)

2Extent of automation

If the chip manufacturer manages all personalization data, then pre-personalization can be fully automated, but administrative effort and complexity increase significantly

Engineering Contradiction:
Improvepre-personalizationVSAvoidadministrative effort
Core Design Contradiction:
Extent of automationVSDevice complexity

Solution Approach 1:

The second part of the personalization data is extracted from the manufacturer's responsibility and kept at the network operator. This extraction reduces the administrative burden on the manufacturer, as they only need to manage the first part of the data and the pre-personalization process, while final personalization is completed by the user with assistance from the network operator.

Inventive Principle:
Principle #2Taking out (Extraction)

3Reliability

If secure production sites are used for personalization, then security is maintained, but manufacturing flexibility and cost-effectiveness are reduced

Engineering Contradiction:
ImprovesecurityVSAvoidmanufacturing flexibility
Core Design Contradiction:
ReliabilityVSEase of manufacture

Solution Approach 1:

The chip is pre-personalized with the first part of personalization data during standard manufacturing processes at regular production sites, not secure facilities. This preliminary action allows the chip to be prepared in advance without requiring secure production sites, while final personalization occurs later in a secure manner through the trust center.

Inventive Principle:
Principle #10Preliminary action

Data Source

PatentEP2289225B1Method for personalizing a safety element of a mobile terminal device
Publication Date: 2015.03.18 GIESECKEDEVRIENT IP
  • EP2289225B1 patent drawingFigure 1
  • EP2289225B1 patent drawingFigure 2
  • EP2289225B1 patent drawingFigure 3

AI summary

The invention relates to a method for personalizing a safety element (SE) of a mobile terminal device (EG), particularly in the form of a smart card chip of a communication terminal device. The invention comprises the pre-personalizing of the safety element (SE) within the course of the production process thereof, and the final personalizing of the safety element (SE) upon the initial use of the terminal device (EG) by the user (N), wherein a communication connection is established between the terminal device (EG) and a trust center (TC) of a communication network operator. Within the course of the pre-personalizing of the safety element (SE), a unique main key (MK) is determined for the safety element (SE) and transferred to the trust center (TC). Within the course of the final personalizing of the safety element (SE), personal data of the user are transmitted to the trust center (TC) upon the initial use of the terminal device (EG), and linked at the trust center together with the main key (MK) to form a modified main key (MK). The safety element (SE) is personalized using the modified main key (MK).