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1.
VANETs have been developed to improve the safety and efficiency of transportation systems (V2V communications) and to enable various mobile services for the traveling public (V2I communications). For VANET technologies to be widely available, security issues concerning several essential requirements should be addressed. The existing security architectures and mechanisms have been studied separately in V2V and V2I networks, which results in duplicated efforts, security modules, and more complex security architectures. In this paper, we propose a unified security architecture and its corresponding security protocols that achieve essential security requirements such as authentication, conditional privacy, non‐repudiation, and confidentiality. To the best of our knowledge, this paper is the first study that deals with the security protocol in V2V as well as the handover authentication in V2I communications. Our proposal is characterized by a low‐complexity security framework, owing to the design and unification of the security architectures and modules. Furthermore, the evaluation of the proposed protocols proves them to be more secure and efficient than existing schemes. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   

2.
激光耦合同步及其在光纤混沌保密通信中的应用   总被引:3,自引:0,他引:3       下载免费PDF全文
本文建立了光纤混沌保密通信耦合同步系统模型,实现了外部光注入分布反馈半导体激光器激光混沌在长距离光纤传输中的耦合同步,证明了光纤的交叉相位调制是限制激光混沌在光纤传输中同步的主要原因,导出了这种传输的极限.该同步系统在长距离光纤混沌模拟和数字保密通信中的数值模拟表明,该系统确有较高的保密性能和反破译能力.光纤混沌保密通信是可以实现的.  相似文献   

3.
针对D2D蜂窝系统通信安全性受资源限制的问题,考虑到蜂窝链路和D2D链路的同频干扰能够为两者带来安全增益,基于此,提出一种基于安全中断概率的D2D用户接入策略。首先理论分析了蜂窝用户和D2D用户的安全中断概率,并给出了基于安全中断概率最小化的D2D用户功率优化算法。在上述分析的基础上,选择安全中断概率最小的D2D用户接入复用蜂窝用户的无线资源,同时提高D2D通信链路和蜂窝上行链路的安全性。最后,仿真结果证明了所提算法的有效性。  相似文献   

4.
A growing application area in mobile communications is mobile teleconference in which a group of mobile users collaborate in an interactive procedure, such as a board meeting, a task force, a scientific discussion, or even a virtual classroom. Wireless communications transmit conversations via radio, making them more susceptible to eavesdropping and unauthorized access than are conversations carried via wires. Therefore, it is crucial to ensure confidentiality and authenticity in a mobile teleconference. The authors design a new secure conference scheme for mobile communications. Based on a modular square root technique, this scheme is secure against eavesdropping, impersonating, and tracking attacks and allows a participant to join or quit a mobile teleconference dynamically.  相似文献   

5.
EPON and WiMAX are two promising broadband access technologies for new-generation wired and wireless access. Their complementary features motivate interest in using EPON as a backhaul to connect multiple dispersed WiMAX base stations. In this article we propose four broadband access architectures to integrate EPON and WiMAX technologies. The integrated architectures can take advantage of the bandwidth benefit of fiber communications, and the mobile and non-line-of-sight features of wireless communications. Based on these integrated architectures, we elaborate on related control and operation issues to address the benefits gained by this integration. Integration of EPON and WiMAX enables fixed mobile convergence, and is expected to significantly reduce overall design and operational costs for new-generation broadband access networks.  相似文献   

6.
Daoud  F. 《IEEE network》1998,12(4):28-38
Future universal broadband mobile services present a challenge for telecommunications architectures, control, and management. The focus of the future mobile (fourth) generation vision is turned from capacity to services, from radio to network-wide issues. New types of applications will evolve that should be supported by an adequate programmable intelligent telecommunications infrastructure. A convergence between telecom and datacom networks will happen based on the communications middleware concept, which will provide universal secure connectivity between mobile users and their applications. Actual specifications of TINA-C do not address all such necessary issues. There is a need for technology evolution, enhancement, and integration to meet these new requirements at different levels. The author the concept of the universal broadband mobile telecommunications systems (UBMTS, or simply UBM) described as fourth-generation mobile systems. The UBMTS objective is both to extend mobile user access to the range of broadband services that will exist for broadband integrated services digital network (B-ISDN) users, and to extend the customization of new services related to personal communications systems (PCS) users  相似文献   

7.
A secure and efficient conference scheme for mobile communications   总被引:3,自引:0,他引:3  
A growing application area in mobile communications is mobile teleconferencing, in which a group of mobile users collaborate in an interactive procedure, such as a board meeting, a task force, a scientific discussion, or even a virtual classroom. Wireless communications transmit conversations via radio, making them more susceptible to eavesdropping and unauthorized access than are conversations carried via wires. Therefore, it is crucial to ensure confidentiality and authenticity in mobile teleconferencing. When deploying secure services in mobile teleconferences, it has to be taken into account that the mobility of users is usually built on portable devices with limited computing capability. A secure conference scheme for mobile communications needs to be executed efficiently on portable devices. We propose a new secure and efficient conference scheme for mobile communications. Based on a modular square root technique, this scheme is secure against eavesdropping, impersonating, and tracking attacks and allows a participant to join or quit a mobile teleconference dynamically. In addition, the scheme is particularly efficient on the mobile user's portable device because the mobile user needs to perform only single modular multiplication plus encryptions and decryptions of a secret key cryptosystem.  相似文献   

8.
Due to the increasing demand for wireless communications, spectral efficiency of transmission schemes has gained a great concern recently. Also, achieving secure wireless communications is of high importance. Recently, physical layer security has been intensively investigated as an extra layer of protection for wireless communications. Directional modulation (DM) has been proposed as a mean to implement physical layer security. Antenna subset modulation (ASM) is a low complexity single beam DM technique suitable for millimeter-wave communications. The small wavelengths nature of millimeter-wave band is exploited to equip a transmitter with a large antenna array, and by randomly choosing few elements of this array for transmitting a symbol, secure communication in a single direction is obtained. This paper provides a study for the performance of broadcasting multi-beams antenna subset modulation (MASM) in which it is desirable to broadcast data streams to different receivers. A statistical model has been driven, and the symbol error rate of MASM using QPSK and secrecy capacity are obtained. Simulation results show that ASM can be used efficiently for multidirectional broadcasting communication, while maintaining its inherent security.  相似文献   

9.
光纤混沌双向保密通信系统研究   总被引:7,自引:0,他引:7       下载免费PDF全文
颜森林 《电子学报》2005,33(2):266-270
本文提出光纤混沌双向保密通信设想,通过耦合光注入半导体激光器激光混沌全光耦合反馈同步系统和光纤传输信道,建立了光纤混沌双向通信系统模型,数值实现了该系统在长距离光纤传输中的同步,详细地分析了系统同步时间随光纤传输长度的关系.证明了光纤的交叉相位调制是限制激光混沌在光纤传输中同步的主要原因,导出了系统传输的非线性相移.数值模拟了具有正弦调制信号的调制频率0.5GHz混沌模拟通信和数字信号调制速率0.4Gbit/s以及20Gbit/s的混沌数字通信以及调制速率0.05Gbit/s 混沌键控通信的应用,计算出光纤混沌数字通信速率和同步误差等关系,还特别分析了系统解码特性和调制带宽,表明系统具有非常好的保密性能和具有高速率通信的能力.光纤混沌双向保密通信是可以实现的.  相似文献   

10.
Secure communications for vehicular ad hoc networks (VANETs) have become an important research issue these years. Many protocols for secure vehicle-to-vehicle communications and vehicle-to-infrastructure communications have been proposed, yet fewer protocols are concerned with secure group communications for VANETs. Of those existing protocols for group communications, some of them form a group of vehicles based on geographical regions and provide broadcasting to the group members with or without message confidentiality. The others allow secure vehicle-to-vehicle communications within a group with session keys, but they do not preserve user privacy for communicating parties within the group. In this paper, we propose a novel group communication scheme for vehicular networks, in which a group is formed by a set of related vehicles of the same purpose, such as a platoon of recreational vehicles targeted for the same tourist spot. The scheme not only offers efficient and secure group communications but also provides privacy preservation for vehicle-to-vehicle communications within a group. Security analysis is given to demonstrate the robustness of the proposed scheme.  相似文献   

11.
12.
文中提出了几种安全的面向服务的Wimax的网络控制架构。为了设计这样的架构,笔者侧重考虑通信安全和满足Wimax潜在的业务需求这两个方面因素。提出的构架里包含两个基本元素:有服务意识,统一的路由配置。另外研究了Wimax建设的关键性技术。通过理论研究,可以为建立更安全更实际可靠的Wimax网络提供一些实际可行的指导意见。  相似文献   

13.
Chaotic synchronization of injected multiple-quantum-well lasers of optical fiber system and a theoretical model of optical fiber chaotic secure communication system are presented by coupling a chaotic multiple-quantum-well laser synchroniza- tion system and a fiber channel. A new chaotic encoding method of chaos phase shift keying On/Off is proposed for optical fiber secure communications. Chaotic synchronization is achieved numerically in long-haul fiber system at wavelength 1.55 μm. The effect of the nonlinear-phase of fiber is analyzed on chaotic signal and synchronization. A sinusoidal signal of 0.2 GHz frequency is simulated numerically with chaos masking in long-haul fiber analog communication at wavelength 1.55 μm while a digital signal of 0.5 Gbit/s bit rate is simulated numerically with c1haos masking and a rate of 0.05 Gbit/s are also simulated numerically with chaos shift keying and chaos phase shift keying On/Off in long-haul fiber digital communica- tions at wavelength 1.55 μm  相似文献   

14.
This paper extends previous research efforts related to the simulation performance modelling and analysis of satellite communication networks. Specifically, the use of low earth orbit (LEO) satellite networks for personal communications is examined. Six different satellite constellation configurations are investigated in a packet‐switched operating environment. Performance metrics examined are the end‐to‐end packet delay and the utilization of satellite channels in the dynamic environment. Realistic and accurate models of the physical satellite network and its terrestrial transmitters require that numerous operating characteristics and assumptions be specified. These are based on proposed design requirements of commercial systems, such as Iridium. Via the use of simulation, we show the relative delay and utilization performance of differing satellite network architectures. From these simulation models, mathematical metamodels are derived for the system delays. These innovative models are used to predict the delay performance of different network architectures not previously simulated. Comparison of these metamodels with simulation results show that metamodels provide an accurate means for performance prediction. Copyright © 1999 John Wiley & Sons, Ltd.  相似文献   

15.
基于固网移动网融合(FMC)的宽带接入网系统   总被引:4,自引:1,他引:3  
文章提出了3种WiMAX无线网络与EPON系统融合架构,融合系统同时具有光网络的高带宽和无线网络的灵活性.根据融合系统的具体架构,讨论了带宽分配,数据转发等系统控制和操作的优化处理.WiMAX与EPON的融合实现了固网移动网在接入网系统中的融合,为新一代宽带接入网技术提供了一个可行方案.  相似文献   

16.
We present parallel algorithms and array architectures for pyramid vector quantization (PVQ) [1] for use in image coding in low-power wireless systems. PVQ presents an alternative to other quantization methods which is especially suitable for symmetric peer-to-peer communications like video-conferencing. But, both the encoding and decoding algorithms have data-dependent iteration bounds and data-dependent dependencies which prevent efficient parallelization of the algorithms for either hardware or software implementations. We perform an algorithmic transformation [2] to convert the data-dependent regular algorithms to equivalent data-independent algorithms. The resulting regular algorithms exhibit modular and regular structures with minimal control overhead; hence, they are well suited for VLSI array implementation in ASIC or FPGA technologies. Based on our parallel algorithms and systematic design methodologies [3], we develop linear array architectures. Both encoder and decoder architectures consist of L identical processors with local interconnections and provide O(L) speed-up over a sequential implementation, where L is the dimension of a vector. The architectures achieve 100% processor utilization and permit power savings through early completion. A combined encoder-decoder architecture is also presented.  相似文献   

17.
Personal communications services (PCS) require low-power radio technologies. One such transceiver architecture employing frequency-hopped spread-spectrum techniques is presented. System features such as antenna diversity with equal-gain combining and sequential hop combining are incorporated into the transceiver design to achieve robust wireless digital data transmission over fading channels. A direct-conversion architecture from radio frequency (RF) to baseband reduces the overall power consumption by eliminating intermediate frequency (IF) components. High-rate frequency hopping with frequency-shift keying (FSK) modulation is implemented using a direct digital frequency synthesis technique. A multiplierless correlation FSK detector, suitable for direct-conversion receivers, has been designed for quadrature noncoherent detection. Robust acquisition algorithms based on energy detection and pattern matching and tracking architectures using digital phase-locked loops are also described for system synchronization. The proposed transceiver is well-suited for low-power PCS applications and other portable wireless communications  相似文献   

18.
嵌入式Linux中安全文件传输系统的设计与实现   总被引:1,自引:0,他引:1  
以Linux操作系统的安全通信为研究方向,介绍了Linux平台下安全文件传输系统的软件设计框架。重点介绍了服务端与客户端的软件设计框架,同时说明了通过使用SSL加密协议为系统加密的方法与流程。该系统作为一款企业级嵌入式智能PDA的子模块,成功应用于企业产品中,效果良好。  相似文献   

19.
The design of Fast Fourier Transform (FFT) integrated architectures for System-on-Chip (SoC) telecom applications is addressed in this paper. After reviewing the FFT processing requirements of wireless and wired Orthogonal Frequency Division Multiplexing (OFDM) standards, including the emerging Multiple Input Multiple Output (MIMO) and OFDM Access (OFDMA) schemes, three FFT architectures are proposed: a fully parallel, a pipelined cascade and an in-place variable-size architecture, which offer different trade-offs among flexibility, processing speed and complexity. Silicon implementation results and comparisons with the state-of-the-art prove that each macrocell outperforms the known works for a target application. The fully parallel is optimized for throughput requirements up to several GSamples/s enabling Ultra-wideband (UWB) communications by using all channels foreseen in the standard. The pipelined cascade macrocell minimizes complexity for large size FFTs sustaining throughput up to 100 MSamples/s. The in-place variable-size FFT macrocell stands for its flexibility by allowing run-time reconfigurability required in OFDMA schemes while attaining the required throughput to support MIMO communications. The three architectures are also compared with common case-studies and target technology.  相似文献   

20.
This paper contrasts the system requirements in the three major applications of fiber optics: digital telecommunications, analog, and local data communications. These comparisons reveal how differing system requirements result in very different architectural design for the fiber optics components, particularly the receiver design. Some alternative receiver architectures are discussed along with performance tradeoffs.  相似文献   

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