端到端语音加密通信的同步信号设计

在语音加密通信过程中,接收方需要通过信号同步来实现精确的解密并恢复出语音信号,而现有方法精确度低且运算量大。为了解决端到端语音加密、解密过程中的同步问题,设计了一种新的基于线性调频信号的同步信号结构。该同步信号是基于带宽经过筛选的线性调频信号产生,避免了因为添加同步信号而使带宽扩展的问题。同步信号结构由两种不同长度的线性调频信号组合而成,不同的组合形式又会产生不同的同步效果。这种结构设计大大提高了同步的精确度和减少了同步运算量。理论和实验证明：该方法可以实现对接收信号帧起始位置进行精确地定位;不会展宽和影响语音信号的频谱;可以透过语音编解码器传输;具有一定的抗噪声性能;运算量比原始结构的同步信号大大减少。     

公众移动通信网络加密语音通信技术研究

公众移动通信网络在给人们日常生活带来便利的同时,开放的网络使得在其上传输的个人隐私和重要商业信息存在泄露的隐患。文中从公众移动通信网络最常使用的传递信息方式——语音通信入手,对基于CS域语音信道和PS域数据信道进行加密语音通信存在的问题进行了分析。同时结合实际测试情况,提出了在这两种信道上实现加密语音通信的方案。     

DCGAN信道下的端到端通信系统设计

针对通信系统中长序列建模存在维度诅咒的问题,提出了一种基于深度卷积生成对抗网络(Deep Convolutional Generative Adversarial Networks, DCGAN)信道建模的端到端通信系统改进方案。该方案将卷积神经网络(Convolutional Neural Network, CNN)和条件生成对抗网络(Conditional Generative Adversarial Network, CGAN)结合,利用CNN与全连接层(Fully Connected Layer, FC)的局部连接特性对传输长序列的信道进行建模。通过对参数重新设计及网络结构调整,获得了适应不同调制方式和信道类型的学习网络,将其应用端到端通信系统中,作为收发机之间梯度反向传播的桥梁。仿真实验表明,改进的DCGAN能够以减小的网络规模以及计算量成功地实现长序列建模,并且表现出良好的泛化能力。此外,将建模结果运用到端到端通信系统设计中,可以获得与传统数字调制系统相近的误比特率性能。     

基于端到端信令的大数据分析系统在VoLTE网络运维中的应用

VoLTE相比于传统的语音业务,具有接续时间短、语音清晰、终端能耗低、平滑回落切换等众多优点,是LTE网络时代语音业务的发展趋势。内蒙移动自Vo LTE商用以来,活跃用户已经超过400万,为了解决新业务的发展和运维分析手段欠缺之间的矛盾,内蒙移动在全区部署了基于端到端信令的大数据分析系统,本文阐述了内蒙移动依托其对VoLTE端到端信令的大数据聚合分析,实现了VoLTE用户网络指标管理、投诉管理、专题分析、VIP用户管理等功能,该系统有效的对Vo LTE业务进行了集中管控、实时保障,实现了对投诉处理的快速定界和全流程端到端业务质量分析。该工具在内蒙移动部署使用后,运维人员的KPI/KQI指标分析能力显著提升,各项指标均达到了集团考核要求,部分指标名列全国前列,内蒙移动的VoLTE网络运维效率得到了很好的提高,通过该系统对终端、用户数、用户画像的精准分析,为市场制定政策提供了强有力的依据,有效支撑了市场发展。     

TETRA系统端到端加密方式中的密钥管理

虽然标准的TETRA系统采用了一些安全方面的措施,但在系统内部信息仍然是以明文方式传输的,当遇上那些对信息传送的安全性非常敏感的用户必须进行端到端的加密时,标准的TETRA系统就不能满足安全的需求.文章对TETRA系统中端到端的加密中密钥管理进行了深入的分析和研究.     

网络安全与加密方案

实现网络安全最有效的办法是加密。数据加密是所有通信安全依赖的基础。本文叙述了在链路、节点和端－端三个通信层次上加密的特点和方法。     

宽带数字集群通信系统端端加密方案研究

文中分析了宽带数字集群通信系统的安全威胁和加密机制,以国产GoTa 4G宽带多媒体集群系统为参考,提出宽带数字集群通信系统的通用端端加密结构模型,设计了一套完整的端端加密方案,并描述了设计思路及实施方法。     

基于信道接入的通信端到端传输时延分析

文中利用信道接入技术对通信端到端的传输时延进行计算,首先将时延分为传输设备传输时延、数据帧长度时延、线路时延,然后计算通信端到端的传输时延,以获得整个通信信号时序序列的计算方法。利用信道接入技术,采用计算模型,计算时延序列中单组信号的出现概率,在此基础上计算出通信端到端的传输时延。最后开展仿真实验,实验结果表明信道接入能够减少计算误差。     

支持移动多媒体的安全中间件

安全以其复杂性和高计算性成为移动通信和移动Internet、特别是移动电子商务发展的瓶颈。根据中间件屏蔽复杂性的特性,设计了一种支持移动多媒体通信的安全中间件模型。该模型主要实现2大安全性服务:基于3GPP标准建议实现移动终端和移动网络的安全通信,在此基础上基于WAP2.0标准实现移动终端与Internet等第3方服务提供商之间的安全通信。主要描述和分析了这个安全中间件模型,并在此基础上提出了一种实现移动终端到移动终端的端到端通信安全的方法。     

随机移动模型下移动自组网无序传输端到端延迟闭解分析

针对移动自组网端到端延迟在封闭形式分析方面的局限性,该文提出一种有效的针对无序传输,单副本两跳中继算法的网络延迟建模方案,并给出其严格的理论延迟上界。首先针对多种随机移动模型,证明了移动节点的相遇间隔时间可归纳为统一表达式。然后,综合分析了媒介竞争、流量竞争、排队延迟等问题,合理划分并精确求解出了各延迟关键时间段,从而构造了数据包排队服务模型。最后推导出移动自组网端到端延迟的封闭形式理论上界。仿真结果表明,该理论延迟与实验数据紧密吻合。     

A heterogeneous‐network aided public‐key management scheme for mobile ad hoc networks

A mobile ad hoc network does not require fixed infrastructure to construct connections among nodes. Due to the particular characteristics of mobile ad hoc networks, most existing secure protocols in wired networks do not meet the security requirements for mobile ad hoc networks. Most secure protocols in mobile ad hoc networks, such as secure routing, key agreement and secure group communication protocols, assume that all nodes must have pre‐shared a secret, or pre‐obtained public‐key certificates before joining the network. However, this assumption has a practical weakness for some emergency applications, because some nodes without pre‐obtained certificates will be unable to join the network. In this paper, a heterogeneous‐network aided public‐key management scheme for mobile ad hoc networks is proposed to remedy this weakness. Several heterogeneous networks (such as satellite, unmanned aerial vehicle, or cellular networks) provide wider service areas and ubiquitous connectivity. We adopt these wide‐covered heterogeneous networks to design a secure certificate distribution scheme that allows a mobile node without a pre‐obtained certificate to instantly get a certificate using the communication channel constructed by these wide‐covered heterogeneous networks. Therefore, this scheme enhances the security infrastructure of public key management for mobile ad hoc networks. Copyright © 2006 John Wiley & Sons, Ltd.     

安全控制管理中心实现GSM安全通信

安全控制管理中心通过蜂窝移动通信网络,可构建蜂窝移动通信安全服务系统,为专用手机提供安全信息自动产生和分配、被动式和主动式安全信息销毁、安全数据控制以及失控专用手机追踪等安全通信管理服务,确保专用手机的使用、操作安全。论文提出专用手机利用在GSM提供的数据信道上建立的虚拟专网(VPN)来实现数字安全话音和安全数据通信,适合在国内外现有的GSM蜂窝移动通信系统上使用。     

移动通信网中端端认证方案的研究

现有的数字移动通信网中提供移动用户与基地地间的保密通信服务,移动用户的间的端端保密通信在移动通信网中还是一个新问题。本文分析了已有端端认证方案的安全性,提出了一种单钥体制域内端端认证方案和一种单钥／双钥混合体制域间端端认证方案。分析结果结果：新方案不仅安全性很高,而且利用于移动端的实现,也便于网络端的密钥管理。     

移动IP的安全隧道实现

在当前的安全机制中，移动IP遇到了一些挑战。在利用网络进行通讯时IPSec协议提供了一个强加密的标准协议（RFC2002）的安全、快速的移动网络。     

基于TFO的移动话音安全传输应用研究

如何在移动通信系统中建立语音业务的安全数据流透明传输通道,是移动通信系统安全语音方案设计的关键技术。移动通信标准中的TFO技术可以避免核心网侧设备的语音编解码功能,实现语音数据流的端到端透明传输通道。研究了GSM、CDMA等移动通信系统中的TFO协商流程、协商原则,重点分析和研究如何基于TFO实现移动通信安全语音业务的技术,为实现高音质的移动通信安全语音业务打下了良好基础。     

A secure group key management scheme for hierarchical mobile ad hoc networks

In this paper, we present a secure group key management scheme for hierarchical mobile ad hoc networks. Our approach aims to improve both scalability and survivability of group key management for large-scale wireless ad hoc networks. To achieve our goal, we propose the following approaches: (1) a multi-level security model, which follows a modified Bell-La Padula security model that is suitable in a hierarchical mobile ad hoc networking environment, and (2) a decentralized group key management infrastructure to achieve such a multi-level security model. Our approaches reduce the key management overhead and improve resilience to any single point failure problem. In addition, we have developed a roaming protocol that is able to provide secure group communication involving group members from different groups without requiring new keys; an advantage of this protocol is that it is able to provide continuous group communication even when the group manager fails.     

NATIONAL SECURITY/EMERGENCY PREPAREDNESS AND DISASTER RECOVERY COMMUNICATIONS VIA ACTS

During the period from early 1993 to 1994, the U.S. National Communication System (NCS), a government agency, sponsored the development and execution of several fixed and mobile experiments using the advanced communications technology satellite (ACTS). The purpose of these experiments was to evaluate the feasibility of integrating an ACTS-like communications system into national security/emergency preparedness (NS/EP) operational scenarios. These experiments focused on clear and secure voice communications in both the fixed and mobile environment. For the mobile experiments, the focus was on the performance of both clear and secure voice in the land-mobile satellite communications channel. For the fixed experiments, the focus was on the use of a T1 terminal for restoration of communication services in the event of a disaster and for remote user communications. The results of these experiments are described in this paper.     

基于WSN的移动Agent安全分析与建模

移动Agent分布计算的加入使得无线传感器网络WSN在低带宽、高容错的条件下实现了其自组织及资源受限等特性。但Agent自身面临的安全威胁及WSN开放的环境成为两技术结合大规模发展的瓶颈。论文详细分析了此方式工作过程及环境特点,并为之选取构造了一种Agent安全框架—ECC密码体制模型,经验证可有效减少网络通信时间、提高通信效率及可靠性,最终使得基于Agent方式的WSN通信更加安全、高效地工作。     

Hexagonal Clustered Trust Based Distributed Group Key Agreement Scheme in Mobile Ad Hoc Networks

Secure and efficient group communication among mobile nodes is one of the significant aspects in mobile ad hoc networks (MANETs). The group key management (GKM) is a well established cryptographic technique to authorise and to maintain group key in a multicast communication, through secured channels. In a secure group communication, a one-time session key is required to be shared between the participants by using distributed group key agreement (GKA) schemes. Due to the resource constraints of ad hoc networks, the security protocols should be communication efficient with less overhead as possible. The GKM solutions from various researches lacks in considering the mobility features of ad hoc networks. In this paper, we propose a hexagonal clustered one round distributed group key agreement scheme with trust (HT-DGKA) in a public key infrastructure based MANET environment. The proposed HT-DGKA scheme guarantees an access control with key authentication and secrecy. The performance of HT-DGKA is evaluated by simulation analysis in terms of key agreement time and overhead for different number of nodes. Simulation results reveal that the proposed scheme guarantees better performance to secure mobile ad hoc network. It is demonstrated that the proposed scheme possesses a maximum of 2250 ms of key agreement time for the higher node velocity of 25 m/s and lower key agreement overhead. Also, the HT-DGKA scheme outperforms the existing schemes in terms of successful message rate, packet delivery ratio, level of security, computation complexity, number of round, number of exponentiations and number of message sent and received that contribute to the network performance.

     

移动通信网络安全发展前景分析

移动通信技术的飞速发展,日益丰富的数据增值业务诸如微博邮件、数据传输、手机支付、多媒体业务等得以应用。而用户更多的个人信息将在移动通信网络中传送,移动通信网络的安全也随之成为移动通信行业界重要的课题。笔者针对移动通信网络中所面临的各种安全威胁和攻击,重点从鉴权认证、用户身份保护、数据加密等方面对移动通信安全现有解决措施的发展情况进行了阐述,并结合移动通信技术的发展分析了其安全措施并提出一些改进方向,最后对移动通信网络安全的前景进行了展望。