• Title, Summary, Keyword: Broadband Wireless Access

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A Coordinated Ciphertext Policy Attribute-based PHR Access Control with User Accountability

  • Lin, Guofeng;You, Lirong;Hu, Bing;Hong, Hanshu;Sun, Zhixin
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.12 no.4
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    • pp.1832-1853
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    • 2018
  • The personal health record (PHR) system is a promising application that provides precise information and customized services for health care. To flexibly protect sensitive data, attribute-based encryption has been widely applied for PHR access control. However, escrow, exposure and abuse of private keys still hinder its practical application in the PHR system. In this paper, we propose a coordinated ciphertext policy attribute-based access control with user accountability (CCP-ABAC-UA) for the PHR system. Its coordinated mechanism not only effectively prevents the escrow and exposure of private keys but also accurately detects whether key abuse is taking place and identifies the traitor. We claim that CCP-ABAC-UA is a user-side lightweight scheme. Especially for PHR receivers, no bilinear pairing computation is needed to access health records, so the practical mobile PHR system can be realized. By introducing a novel provably secure construction, we prove that it is secure against selectively chosen plaintext attacks. The analysis indicates that CCP-ABAC-UA achieves better performance in terms of security and user-side computational efficiency for a PHR system.

Design and Implementation of the subscriber MAC protocol in the BWA system

  • Hwang, You-Sun;Kim, Eung-bae
    • Proceedings of the IEEK Conference
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    • pp.569-572
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    • 2003
  • The broadband wireless access industry, which provides high-tate network connections to stationary sites, has matured to the point at which it now has a standard for second-generation wireless metropolitan area networks. IEEE Standard 802.16, with its WirelessMAN air interface, set the stage for widespread and effective deployments worldwide. This paper presents an implementation of media access control that can be applied to BWA (Broadband Wireless Access) system. Medium access control (MAC) is a key issue in multi-access networks where a common channel is shared by many users. The designed MAC prototype roughly consists of MAC Hardware and MAC Software. The MAC Hardware part includes timing process, MAC transmission control, MAC reception control, and CRC/HCS process. The MAC Software part includes control of MAC signaling, network interface, and Physical (PHY) control. The designed MAC protocol will be integrated with the PHY of BWA in future and we can test overall system performance of MAC and PHY.

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Analysis of Traffic Characteristics in Broadband Wireless Access (광대역 무선 액세스 환경에서의 트래픽 특성분석)

  • Koo Hye-Ryun;Lim Seog-Ku
    • Proceedings of the Korea Contents Association Conference
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    • pp.346-351
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    • 2005
  • 인터넷의 급속한 보급과 대용량 멀티미디어 서비스에 대한 요구 증가로 댁내 또는 중소사업장에 대한 광대역 무선 액세스(Broadband Wireless Access) 수요가 증가하고 있다. 기존의 무선랜은 도달거리가 짧아서 이동 중일 때나 AP(Access Point)에서 멀어지면 통화품질이 저하되고, 무선인터넷은 사용 비용이 높다. 이를 보안한 광대역 무선 인터넷 시스템인 와이브로(WiBro: Wireless Broadband Internet)는 휴대폰과 무선랜의 중간 영역에 위치한 이동초고속인터넷서비스이다. 본 논문에서는 IEEE 802.16 BWA을 기반으로 멀티미디어 서비스를 제공하기 위해서 서비스별 트래픽 모델과 특성을 분석하고, 다양한 트래픽 혼합 비율에 따라 시뮬레이션을 수행하였으며, 이를 토대로 최종적으로는 WiBro 시스템에서 수용 가능한 최대 가입자 수를 산출하였다.

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Multimedia Ad Hoc Wireless LAMs with Distributed Channel Allocation Based on OFDM-CDMA (OFDM-CDMA에 기반을 둔 분산 채널 할당 구조를 갖는 멀티미디어 Ad Hoc 무선 LAM에 관한 연구)

  • Yang, Hyun-Ho
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.9 no.5
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    • pp.965-972
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    • 2005
  • We propose a new resource management scheme, Distributed Channel Allocation Protocol (DCAP), for multimedia Ad Hoc Wireless LANs (AWLANS). This scheme implements a Qualify-of-Service (QoS) providing distributed resource management on the Orthogonal Frequency Division Multiplexing-Code Division Multiple Access (OFDM-CDMA) channel architecture. According to the performance evaluation results for MPEG traffic sources, DCAP can be a good choice of resource management scheme for AWLANs supporting multimedia services on the Broadband Wireless Access(BWA)-type physical layer.

Analysis of Termination Capacity in IEEE 802.16 Broadband Wireless Access Environments (IEEE 802.16 BWA 환경에서의 가입자 수용용량 분석)

  • Lim Seog-Ku
    • The Journal of the Korea Contents Association
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    • v.5 no.6
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    • pp.65-73
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    • 2005
  • Request about fast diffusion of internet and high-capacity multimedia service is increasing day after day. Because existent wireless LAN is short range, if subscriber is far away in base station transceiver system(Base Station), subscriber's quality of service becomes low, and wileless internet is expensive. Lately, WiBro(Wireless Broadband Internet) system that is developed in domestic by world first, is high-speed portable internet service that is situated in middle area of mobile phone and wireless LAN. In this paper, service traffic model and characteristics are analyzed to provide multimedia service based on IEEE 802.16 BWA accomplishes base of WiBro and simulation is conducted according to various traffic mixing ratio. Finally, on the basis of these simulation results, maximum allowable number of subscriber per cell is calculated.

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Low-complexity implementation of OFDMA timing delay detector with multiple receive antennas for broadband wireless access (광대역 무선 액세스를 위한 다중 수신안테나를 갖는 OFDMA 시스템의 낮은 복잡도의 타이밍 딜레이 추정기 구현)

  • Won, Hui-Chul
    • Journal of the Korea Industrial Information Systems Research
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    • v.12 no.3
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    • pp.19-30
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    • 2007
  • In this paper, we propose low-complexity implementation of orthogonal frequency division multiple access (OFDMA) timing delay detector with multiple receive antennas for broadband wireless access (BWA). First, in order to reduce the computational complexity, the detection structure which rotates the phase of the received ranging symbols is introduced. Second, we propose the detection structure with the N-point/M-interval fast Fourier transform structure and a frequency-domain average-power estimator for complexity reduction without sacrificing the system performance. Finally, simulation results for the proposed structures and complexity comparison of the existing structure with the proposed detectors are presented.

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STBC SC-FDE based on LS-Algorithm for Fixed Broadband Wireless Access System

  • Kim Han Kyong;Hwang Ho Seon;Baik Heung Ki
    • Proceedings of the IEEK Conference
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    • pp.596-599
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    • 2004
  • We propose an Alamouti-like scheme for combining space-time block coding with single-carrier frequency-domain equalization(SC-FDE) in fixed broadband wireless access environment. With two transmit antennas, the scheme is shown to achieve significant diversity gains at low complexity over frequency-selective fading channels

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Dynamically Alternating Power Saving Scheme for IEEE 802.16e Mobile Broadband Wireless Access Systems

  • Chang, Jau-Yang;Lin, Yu-Chen
    • Journal of Communications and Networks
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    • v.14 no.2
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    • pp.179-187
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    • 2012
  • Power saving is one of the most important features that extends the lifetime of portable devices in mobile wireless networks. The IEEE 802.16e mobile broadband wireless access system adopts a power saving mechanism with a binary truncated exponent algorithm for determining sleep intervals. When using this standard power saving scheme, there is often a delay before data packets are received at the mobile subscriber station (MSS). In order to extend the lifetime of a MSS, the battery energy must be used efficiently. This paper presents a dynamically alternating sleep interval scheduling algorithm as a solution to deal with the power consumption problem. We take into account different traffic classes and schedule a proper sequence of power saving classes. The window size of the sleep interval is calculated dynamically according to the packet arrival rate. We make a tradeoff between the power consumption and packet delay. The method achieves the goal of efficiently reducing the listening window size, which leads to increased power saving. The performance of our proposed scheme is compared to that of the standard power saving scheme. Simulation results demonstrate the superior performance of our power saving scheme and its ability to strike the appropriate performance balance between power saving and packet delay for a MSS in an IEEE 802.16e mobile broadband wireless access system.

An IPv6 based Fast Handover Deployment Scheme for WiBro Networks (광대역 무선 인터넷 망에서 IPv6 기반의 고속 핸드오버 도입을 위한 방안)

  • Shim, Min-Sik;Kim, Hwa-Sung
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.31 no.11A
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    • pp.1101-1112
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    • 2006
  • With the recent growth in demand for high-data rate multimedia services in the wireless environments, the Mobile Broadband Wireless Access (MBWA) technologies, such as WiBro (Wireless Broadband internet) system, are gradually coming into the spotlight. Unlike the conventional mobile communication networks based on cellular system, the WiBro system basically consists of IP based backbone networks that will be ultimately deployed by Ipv6 (IP version six) based backbone networks according to the All-IP trend for the network evolution. In such wireless mobile environments, it is needed to support the mobility management protocol on network layer as well as physical layer and Medium Access Control (MAC) layer in WiBro system. Accordingly, in this paper, we propose a fast handover scheme for improving the handover performance in IPv6 based WiBro system and show that the proposed scheme achieves loss-free and low handover latency during inter-subnet movement of the mobile stations through the simulation.

Rain Attenuation Prediction using Combined Raindrop Size Distribution for the Fixed Services of HAPS System

  • Kim, Yang-Su;Ku, Bon-Jun;Park, Jong-Min;Ahn, Do-Seob
    • Proceedings of the IEEK Conference
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    • pp.527-530
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    • 2002
  • The frequencies for HAPS used in fixed wireless access are allocated in the millimeter wave bands. The systems using these frequencies can have a serious impact on the radio communication qualities due to rain. In this paper, we compare the specific rain attenuation using CM(combined) raindrop size distribution with those using different sevral raindrop size distributions for the frequency bands 28/48㎓. The rain attenuations using CM raindrop size distribution for the path between the earth and HAPS platform according to the elevation angle are described.

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