TLS - Key Management

Key management system

TLS essentially relies on two key management systems:

• Public-key management system: Because TLS is designed for use in open environments, it relies on an external key management system that governs the public-key pairs required by TLS users (which is all users if mutual entity authentication is required, or just users who are servers if only the unilateral entity authentication is required). This key management system is beyond the scope of a TLS specification and is relied on to establish and maintain public-key certificates and information concerning their validity. If this system fails, then the security provided by TLS is undermined.

• Symmetric key management system: Within TLS is a self-contained symmetric key management system. TLS is used to generate symmetric session keys, which are designed to have limited lifetimes.