Abstract: SPKI/SDSI is a flexible and extensible decentralized security model that provides authentication，confidentiality，
and access control.However，SPKI/SDSI certification chains are not suitable for large scale，highly dynamic environments such as computational grids.This paper extends the SPKI/SDSI model by including an opinion model based on subjective logic.
The model can be flexibly applied to computational grid.

摘要： SPKI/SDSI 是一种灵活且可扩展的分散的安全模型，它能够提供认证、保密和访问控制。然而，SPKI/SDSI 证书链并不适合大规模、高动态的环境，比如计算网格。通过观念模型基于主观逻辑对SPKI/SDSI 安全模型进行了扩展，提出了一种扩展的SPKI/SDSI 模型。该扩展模型可以灵活应用于计算网格。