如何在安全要求高、节点资源极其有限的情况下提供有效的密钥管理，一直是分布式无线传感网研究的挑战之一。近年来很多研究方案陆续出台，其中著名的方案就是EG。本文在EG方案的基础上，提出了一种新的密钥建立和更新方案UEGS，并分析了该方案的可行性、效率以及安全性。

Key management has long been a challenging problem in distributed wireless sensor networks(DWSN) due to their high security requirements and strict resource constraints. Many schemes have been developed to establish keys in DWSN, including the famous EG scheme. Based on this classic scheme, this paper proposes a new key establishment and rekeying scheme: UEGS. The analysis in this paper demonstrates its feasibility, efficiency and security for key establishment and maintenance in DWSN.