Abstract: Because a reliable end-to-end link is not available in deep space DTN (delay tolerant networks), the rekey process is not implemented efficiently by a key management center in key management. In order to deal with the question, this paper puts forward an autonomic group key management scheme, a key management center designs a logical key tree based on one-encryption-key multi-decryption-key key protocol, in which each leaf node corresponds to a network member having a secret decryption key, each non-leaf node corresponds to an encryption key which is computed by the secret decryption keys of leaf nodes that are in the subtree of non-leaf nodes. In proposed scheme, the capability of each member is same to the key management center on rekeying, and the forward security and backward security is guaranteed. With theory analysis, the rekeying message of the proposed scheme is half of LKH (logical key hierarchy) scheme when new node joins, and message cost is constant value when node leaves, so the proposed scheme is suitable to deep space DTN.

Key words: deep space DTN, autonomic group key management, multi-decryption-key key protocol

摘要： 深空DTN（delay tolerant networks）网络难于提供可靠的端到端服务，因此在组密钥管理中密钥管理中心不能及时有效地执行密钥更新过程。针对这一问题，提出了一种自主组密钥管理方案。通过单加密密钥多解密密钥密钥协议设计逻辑密钥树，树中的叶子节点为成员的秘密加密密钥，非叶子节点为公开加密密钥，组成员具有和密钥管理中心相同的能力——更新逻辑密钥树中公钥，并且保证组密钥更新的前向和后向安全性。与LKH（logical key hierarchy）方案对比，建议的组密钥管理方案加入更新消息开销减少一半，退出更新消息开销为常数，与组成员规模无关，无需密钥管理中心支持，满足长延时深空DTN网络安全需求。

关键词: 深空DTN, 自主组密钥管理, 多解密密钥密钥协议