针对典型蜂窝网络LTE-A网络的切换认证问题，本文通过引入SDN（Software Defined Network，软件定义网络），提出了软件定义LTE-A异构网络架构，在中心控制器中共享UE（User Equipment，用户设备）的安全上下文信息，以实现简化切换认证过程，提高认证效率的目标.中心控制器的加入，使蜂窝与核心网通信时需要增加一次信令开销，而LTE-A网络的标准切换认证方法过于复杂，应用在软件定义LTE-A异构网络中，会产生较多的信令开销.基于代理签名的切换认证方法，使UE在验证身份时不用经过核心网，减少了信令开销.在安全性相同的情况下，基于椭圆曲线的加密体系比基于RSA的加密体系计算量更小，有利于减少中心控制器的计算压力.本文采用椭圆曲线代理签名方法，提出了一种新型的切换认证协议，并运用着色Petri网进行建模和仿真分析.仿真结果表明，该协议是有效的，且安全性更高.
Aiming at the handover authentication in the LTE-A,SDN is introduced and a new heterogeneous network framework named Software Defined LTE-A is proposed.This framework simplifies the handover authentication via the sharing of security context information in the Controllers.The use of Controller leads to one more communication overhead when the base station communicates to the core network.The standard handover authentication in LTE-A is a complex system that will generate a lot of communication overhead.The handover authentication based on proxy signature make the UE(User Equipment) need not to communicate to core network when UE is authenticated,which reduces the communication overhead.Compared to RSA Cryptography,the Elliptic Curve Cryptography needs less computation that will decrease the computation overhead in the Controller.Adopted the proxy signature based on the Elliptic Curve,a new handover authentication protocol is proposed,and is modeled,simulated,and analyzed by the Colored Petri Nets.The results of the simulation show that the proposed handover authentication is efficient and more secure.
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2017, Vol. 45 
