Key Distribution Mechanism and hierarchical Protection

Key Distribution Mechanism and hierarchical Protection

Zhang Shuai

Currently, key management systems used by mainstream IC card application systems mainly include key management based on public key infrastructure and key management based on symmetric algorithms.

PKI is a unified key Publishing, management, and use system based on public key algorithms. It is not a single object or software, but a set of services provided by the collaboration of many interconnected components, these services allow users to easily and easily use the public key system to solve existing security problems.

The basic idea of generating keys hierarchically is to use keys to protect keys. That is, the key ki at the I layer is used to protect the key Ki + 1 at the I + 1 layer, and I is protected by the key I-1 at the Ki-1 layer. This hierarchical method can greatly improve the system security. Because the underlying keys can be designed as a protocol constantly changing, the entire key management system becomes a dynamic feature.

The key dispersion algorithm is fixed, and there is a corresponding algorithm flow chart in the construction or PBOC standards. The key dispersion mechanism is an effective means to protect key security. Key dispersion makes keys used in each IC card transaction different, achieving "one card, one password ", it is also required to work with the control key during key operation to improve the security of key usage.

Symmetric Key Management Algorithms Based on symmetric algorithms require communication parties to share a secret data as an encryption key, and the management and exchange of keys becomes a little complicated. Symmetric algorithms are often used in identity authentication protocols. In this process, key management is also based on symmetric algorithms. In the Key Management System Based on symmetric algorithms, the IC card can generate hardware random numbers and other features, you can use the changed Pw for each user ID during identity authentication, this invalidates replay attacks.

Compared with public key algorithms, symmetric algorithms have the advantages of high computing speed and low resource usage. Therefore, they are widely used in IC card application systems. The key dispersion mechanism and the idea of hierarchical protection are also derived from symmetric key management.