长延时非可靠端到端深空网络自主密钥管理研究

Deep space network is an important technology of deep space probe, due to deep space network has characteristics including long distance,long time delay and difficult to maintenance in time, therefore it is against more threaten than ground network. Existed rekeying schemes which based on reliable end-to-end and short time-delay are not suitable for the security and efficiency requirement of deep space network. To solve the question, this topic will find the special threaten of deep space network, study the impaction that long time delay interfere with rekeying efficient and security, analyze the function of one-encryption-key multi-decryption-key encryption/decryption algorithm for rekeying, the algorithm has capability to improve the efficiency of key distribution, key agreement and rekeying by virtue of a secret encrypted by a key can be decrypted with different keys successfully, and build the relationship of trade-off between time-delay and computation cost in rekeying, design the localized rekeying strategy and autonomous key management scheme. In this topic, firstly a autonomous key agreement is put forwarded, which guarantees feasibility and security on rekeying even if a key management center is absent or a reliable end-to-end link is not available; secondly a key management model based on deep space topology structure is issued to improve the efficiency of key agreement because the priori knowledge is reduced including graph topology, energy level, link state and so on; thirdly an anonymous entity authentication protocol is put forward to deal with the question that the member of deep space network could discard package as selfish behavior; finally our proposed key management schemes security is verified with provable security theory, and these schemes are realized to testify the feasibility with simulation experiments. Our research result enrich key management, and deal with the efficient question on key distribution, key agreement and rekeying in long time delay deep space network, so our work provide the theoretical and practical basis for deep space network security protocol...

深空网络是未来深空探索的重要技术之一，具有远距离、长延时和较难实时维护的特点。基于可靠端到端服务和短延时的无线网络密钥更新难以满足深空网络安全和效率要求。针对该问题，本课题研究深空网络长延时对密钥管理效率和安全性的影响，分析单加密密钥多解密密钥加密/解密算法对密钥更新作用，建立密钥更新中延时和计算开销的折中关系，设计本地密钥自主更新策略。研究结果为深空网络设计自主密钥管理方案，在缺失密钥管理中心的情况下，保证密钥更新的可行性和安全性，本地成员通过折中延时和计算开销选择不同的更新策略；设计适合深空拓扑结构的密钥管理方案，提高密钥协议协商性能，减少密钥管理的全局先验知识；设计匿名性实体认证协议，防止深空网络选择丢包的自私行为；最后通过可证明安全性理论和仿真实验证明方案的安全性和可行性。研究结果解决深空网络长延时和非可靠端到端下密钥分发、协商和更新问题，为深空网络安全协议设计奠定理论和实践基础。

研究深空网络背景下的安全问题，从空间属性、拓扑结构、安全协议研究、分析和设计群组密钥管理方案。提出结构化公开加密密钥组织模型和结构，支持密钥管理资源开销的折中策略，满足密钥独立性的群组解密密钥集合成员具有有限修改公开加密密钥的能力，使得群组成员在无可信中心支持下采用自配置方式更新公开加密密钥，更新后的公开加密密钥不会破坏非更新成员解密密钥的合法性。建议的公钥结构丰富了解密密钥和加密密钥之间的关系，扩展了群组密钥操作，适合环境苛刻的网络群组密钥管理。提出一种新颖的安全性更高的单加密多解密组播密钥管理方案，该方案不仅具有单加密密钥加密的信息被多个不同解密密钥解密的性质，而且利用门限密钥中共享秘密乘积机制将成员的主密钥碎片分为两个因子，主密钥更新依赖秘密乘积的部分因子的更新，成员解密密钥因子在密钥更新中保持不变，减少密钥更新时延。在结构化公开加密密钥组织模型基础上，提出一种基于K级门限密钥的自治群组密钥管理方案和基于身份的无交互的动态群组密钥管理方案。在K级门限密钥的自治群组密钥管理方案中，通过多级共享的方式使得高层的密钥碎片被多个解密密钥共享，成员根据自身空间属性选择密钥碎片，满足安全管理的异构性。在群成员加入和退出中，具有密钥独立性的密钥更新操作保证非更新成员密钥碎片的合法性，非更新成员无需与更新成员交互，密钥更新效率与网络规模无关，解决密钥更新扩散问题。在交互的动态群组密钥管理方案中，公开加密密钥对应多个具有密钥独立性的秘密解密密钥，并绑定成员身份，群组密钥操作中只需更新公开加密密钥，非退出或加入成员的私有解密密钥保持不变。在性能上，该方案中非更新成员无需交互，密钥更新消息负载与网络规模无关，解决密钥更新的扩散问题，隐含的身份认证进一步减少延时；在安全性上保证前向和后向安全性。因此建议的方案适合快速移动和拓扑频繁变化的空间飞行器网络。此外，在研究工作中从拓扑动力学角度研究环形拓扑结构下密钥材料发布的优化策略，随机预分配模型下密钥材料管理，以及宽覆盖下空间网络身份认证的区域自治等问题。这些工作进一步丰富了空间网络的安全管理策略和密钥管理手段，为未来空间技术提供新思路、新方法和新技术。