Policy-based security management for large dynamic groups: an overview of the DCCM project

The Dynamic Cryptographic Context Management (DCCM) project efficiently provides security for very large, dynamically changing groups of participants. The DCCM system has two novel distinguishing characteristics. First, policy plays a key role in DCCM. Groups at all levels have policies. These policies are represented; they are negotiated; they are managed; and a cryptographic context-an unambiguous set of mechanisms and configuration-is created to make particular interactions possible subject to these policies. Second, DCCM implements a scalable key management system based on One-way Function Trees (OFT) that can handle group sizes up to 100000 members and can dynamically handle members entering and leaving groups.