针对空间时延容忍网络高延时、连接易中断等特点,提出一种非交互式的密钥交换协议,并在随机预言模型下对其进行安全性证明。该协议无需用户交互即生成一个共享的对称密钥,可消除对传统公钥基础设施中证书的依赖,减少通信与存储开销,同时避免基于身份的公钥加密体制中存在的密钥托管问题。分析结果表明,该协议未使用耗时的双线性对运算,具有较高的计算效率,更适用于计算能力受限、能量资源宝贵的空间环境。 Aiming at the characteristics of high delay of network delay and easy connection interruption, this paper proposes a non-interactive key exchange protocol and proves its security under the random oracle model. The protocol generates a shared symmetric key without user interaction, eliminates reliance on certificates in traditional public key infrastructure, reduces communication and storage overhead, and avoids key escrow problems that exist in identity-based public key cryptosystems. The analysis results show that the proposed protocol does not use time-consuming bilinear pairing and has high computational efficiency. It is more suitable for computing environment with limited computing power and precious energy resources.