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LTE网络非接入层安全机制研究摘要随着个人通信的迅猛发展，个人需求对于通信网络提出了更高的要求。为了适应业务带宽、服务质量以及网络覆盖等多方面需求，以及应对各种新的宽带无线接入技术对3G系统形成的挑战，3GPP（第三代合作伙伴计划）组织于2004年12月启动了无线接入网LTE(LongTermEvolution，长期演进)研究项目。目前，LTE正迅速展开规模试验和国际化部署，而我国三大运营商的LTE网络亦是已经或即将投入商用。由于移动通信信道的特殊性，信息传递是通过无线信道进行，比其他网络更容易遭受攻击，从而在制定下一代移动通信系统LTE/SAE标准的过程中，安全性是一个需要着重考虑的因素。本论文从LTE的网络架构着手，主要对LTE网络非接入层安全机制进行讨论、研究。由于NAS信令安全包括加密和完整性保护两个方面，所以理论方面，本论文分别从NAS完整性保护和NAS加密解密机制两方面展开进行讨论。完整性方面，以EPS安全上下文为切入点进行了详细的研究，然后对其中的密钥以及NAS的认证过程进行了讨论。加密机制方面对于加密、解密原理进行了详细的介绍。实践方面，对其中的加密解密机制使用C语言编程实现加密NAS信令的解密工作（只针对使用EEA2算法加密的NAS信令）。从理论和实践两个方面研究LTENAS的安全机制。关键词LTE非接入层安全机制EEA2算法ResearchonNASSecurityMechanismofLTENetworkABSTRACTASaresultofthefastdevelopingofpersonalcommunication，peoplehavehigherrequirementforthenetwork.Tosatisfytherequirementofservicebandwidth，qualityofservice，coverofnetwork，andcopewiththechallengeofotherwirelessaccesstechnologyagainst3G,3GPPorganizationstartupthewirelessaccessnetworkLongTermEvolution(LTE)project.Atpresent,LTEisrapidlyexpandedscaletestandinternationaldeployment,whiletheLTEnetworksofChina'sthreeoperatorsarealsohasbeenorwillbeputintocommercial.Becauseoftheparticularityofmobilecommunicationchannel，messagesaretransferredthroughwirelesschannel．ItCanbeattackedmorethanothernetworks．SosecurityisakeyfactormustbeconsiderationwhenmakingthenextgenerationmobilecommunicationstandardLTE/SAE．ThispaperintroducestheLTEnetworkarchitectureofLTEnetworkfirstandthenresearchestheNASsecuritymechanisms.BecauseNASsignalingsecurityincludesencryptionandintegrityprotection,inthispapertheorydiscussionisdividedintotwoparts.Integrity,theEPSsecuritycontextisdiscussedfirstly，thenthekeysandauthenticationareintroduced.AndthenEncryptionmechanismisintroducedindetail.Besides，aprogramwhichcandeciphertheEncryptedNASsignaling（onlytalkingaboutthoseEncryptedbyEEA2）iswritteninClanguage.So，theNASsecuritymechanismsisintroducedintwowaysofacademicandpractical.KEYWORDSLTENASsecuritymechanismsEEA2I目录摘要...........................................................0第一章绪论.....................................................11.1引言.........................................................................................................11.2选题背景及意义.....................................................................................11.3研究内容.................................................................................................21.4论文组织与结构.....................................................................................2第二章LTE网络与LTENAS层.....................................42.1LTE网络体系架构..................................................................................42.2安全层次.................................................................................................42.2.1AS信令安全.................................................................................52.2.2用户安全......................................................................................52.3LTENAS层及NAS信令安全...............................................................52.3.1LTENAS层..................................................................................52.3.2NAS信令安全..............................................................................6第三章NAS完整性保护...........................................73.1NAS信令完整性保护.............................................................................73.2EPS安全上下文及其处理......................................................................73.2.1EPS安全上下文的分类...............................................................73.2.2EPS安全上下文的建立...............................................................83.2.3EPS安全上下文的数量...............................................................93.3密钥体系...............................................................................................103.4GUTI重分配过程.................................................................................113.5EPS认证及安全协商............................................................................123.5.1AKA过程...................................................................................133.5.2NASSMC过程..........................................................................14第四章NAS加密解密机制........................................154.1加密、解密方法...................................................................................154.2解密过程...............................................................................................154.3解密的输入参数及密钥.......................................................................164.4NAS信令加密算法...............................................................................164.5NAS信令消息加密情况.......................................................................17第五章程序实现及结果分析......................................19II5.1程序实现内容.......................................................................................195.2128-EEA2算法.....................................................................................195.3AES算法...............................................................................................195.4程序分析.....................