无线电工程

LTE用户切换时的密钥管理在很大程度上关系着用户安全,切换密钥管理包括密钥的生成、分发、更新和撤销。对现有长期演进(Long Term Evolution,LTE)网络切换密钥管理更新机制进行简要介绍,包括X2和S1切换密钥更新方案。针对X1切换仅有两跳前向密钥隔离的安全缺陷,借鉴S1切换方案设计思想,提出一跳前向密钥隔离的X2切换密钥更新方案(OFKS-X2),并对OFKS-X2密钥更新方案进行了安全性和实用性分析。结果表明,OFKS-X2密钥更新方案能够提供一跳前向密钥隔离,对协议有效性影响不大,且用户的消息工作量没有变化,网络侧的消息处理复杂度略有增加,用户侧计算量基本不变,网络侧计算量略有增加。

Key management has a big impact on LTE user security in handover process. Handover key management includes handover key generation,distribution,refresh and revocation. In this paper,we will introduce the handover key refresh mechanism in detail,including X2 handover key refresh scheme and S1 handover key refresh scheme. Finally,with reference to the S1 handover scheme,an enhanced X2 handover key refresh scheme OFKS( One-hop Forward Key Separation) X2 handover key refresh scheme is put forward to over come the disadvantage of the original one in LTE which can only provide two-jump forward security by advancing the time when MME is involved in the agreement.Analysis results show that the OFKS-X2 key update scheme can provide a jump forward to the key and has little effect on the protocol. No changes happen in the user's message workload and side calculation. However the complexity of message processing and calculation in the network side is slightly increased.