• Title/Summary/Keyword: control network protocol

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Secure Discovery Method of Devices based on a Home Server (홈서버기반의 유효한 디바이스 검색 방법)

  • Kim Do-Woo;Kim Geon-Woo;Lee Jun-Ho;Han Jong-Wook
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2006.05a
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    • pp.745-748
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    • 2006
  • With a home network, a device can dynamically join a home network, obtain an IP address, convey its capabilities, and learn about the presence and capabilities of other devices. Devices can subsequently communicate with each other directly. Device discovery protocol defines how network services can be discovered on the network. In this paper, we propose the secure discovery method of devices that uses mutual authentication with symmetric key between devices. This method that we present distributes symmetric-key to home network devices by the home server. Using this key, mutual authentication is performed between home appliances. It enables any appliance under any middleware's control to securely communicate any other appliances.

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Adaptive Wireless Network Coding for Infrastructure Wireless Mesh Networks

  • Carrillo, Ernesto;Ramos, Victor
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.13 no.7
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    • pp.3470-3493
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    • 2019
  • IEEE 802.11s-based infrastructure Wireless Mesh Networks (iWMNs) are envisaged as a promising solution to provide ubiquitous wireless Internet access. The limited network capacity is a problem mainly caused by the medium contention between mesh users and the mesh access points (MAPs), which gets worst when the mesh clients employ the Transmission Control Protocol (TCP). To mitigate this problem, we use wireless network coding (WNC) in the MAPs. The aim of this proposal is to take advantage of the network topology around the MAPs, to alleviate the contention and maximize the use of the network capacity. We evaluate WNC when is used in MAPs. We model the formation of coding opportunities and, using computer simulations, we evaluate the formation of such coding opportunities. The results show that as the users density grows, the coding opportunities increase up to 70%; however, at the same time, the coding delay increments significantly. In order to reduce such delay, we propose to adaptively adjust the time that a packet can wait to catch a coding opportunity in an MAP. We assess the performance of moving-average estimation methods to forecast this adaptive sojourn time. We show that using moving-average estimation methods can significantly decrease the coding delay since they consider the traffic density conditions.

A Study on the Development of the SCADA System using the Internet (인터넷을 이용한 SCADA 시스템 구축에 관한 연구)

  • Park, I.K.;Yoon, K.K.;Kim, Y.S.;Lee, S.G.;Ahn, B.W.
    • Proceedings of the KIEE Conference
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    • 1998.07g
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    • pp.2373-2376
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    • 1998
  • This paper describes the development of the SCADA(Supervisory Control and Data Acquisition) system which can be controlled via the Internet. In this paper, the SCADA system is composed of a number of microprocessor-based RTU(Remote Terminal Unit)s, a MMI(Man Machine Interface) host, a SCADA server, and SCADA clients. There are two protocols used in the system. Each RTU and the MMI host are connected by a RS-485 line and CSMA/CD(Carrier Sense Multiple Access / Collision Detection) protocol is used to communicate with each other. TCP/IP(Transmission Control Protocol/Internet Protocol) is used among the MMI host, the SCADA server, and SCADA clients. The equipments installed in the field are controlled by a number of RTUs. The function of the MMI host is to acquire real-time data from RTUs and control them. The SCADA server supports data transfer between the networked MMI host and the SCADA client on the web-server through TCP/lP. Data transfer is possible regardless of the type of network only if there are TCP/lP Winsock-compatible stack driver. The SCADA client is implemented as the shape of web-page by means of JAVA language. Therefore, it runs on a web-browser such as Netscape and Explorer, and allows a number of users to access this SCADA system.

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Performance Analysis of Opportunistic Spectrum Access Protocol for Multi-Channel Cognitive Radio Networks

  • Kim, Kyung Jae;Kwak, Kyung Sup;Choi, Bong Dae
    • Journal of Communications and Networks
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    • v.15 no.1
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    • pp.77-86
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    • 2013
  • Cognitive radio (CR) has emerged as one of effective methods to enhance the utilization of existing radio spectrum. Main principle of CR is that secondary users (SUs) are allowed to use the spectrum unused by primary users (PUs) without interfering PU's transmissions. In this paper, PUs operate on a slot-by-slot basis and SUs try to exploit the slots unused by PUs. We propose OSA protocols in the single channel and we propose an opportunistic spectrum access (OSA) protocols in the multi-channel cognitive radio networks with one control channel and several licensed channels where a slot is divided into contention phase and transmission phase. A slot is divided into reporting phase, contention phase and transmission phase. The reporting phase plays a role of finding idle channels unused by PUs and the contention phase plays a role of selecting a SU who will send packets in the data transmission phase. One SU is selected by carrier sense multiple access / collision avoidance (CSMA/CA) with request to send / clear to send (RTS/CTS) mechanism on control channel and the SU is allowed to occupy all remaining part of all idle channels during the current slot. For mathematical analysis, first we deal with the single-channel case and we model the proposed OSA media access control (MAC) protocol by three-dimensional discrete time Markov chain (DTMC) whose one-step transition probability matrix has a special structure so as to apply the censored Markov chain method to obtain the steady state distribution.We obtain the throughput and the distribution of access delay. Next we deal with the multi-channel case and obtain the throughput and the distribution of access delay by using results of single-channel case. In numerical results, our mathematical analysis is verified by simulations and we give numerical results on throughput and access delay of the proposed MAC protocol. Finally, we find the maximum allowable number of SUs satisfying the requirements on throughput and access delay.

Hybrid Priority Medium Access Control Scheme for Wireless Body Area Networks (무선 인체통신 네트워크를 위한 복합 우선순위 MAC 기법)

  • Lee, In-Hwan;Lee, Gun-Woo;Cho, Sung-Ho;Choo, Sung-Rae
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.35 no.9B
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    • pp.1305-1313
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    • 2010
  • Last few years, wireless personal area network (WPAN) has been widely researched for various healthcare applications. Due to restriction of device hardware (e.g., energy and memory), we need to design a highly-versatile MAC layer protocol for WBAN (Wireless Body Area Network). In addition, when an emergency occurs to a patient, a priority mechanism is necessitated for a urgent message to get through to the final destination. This paper presents a priority mechanism referred to as hybrid priority MAC for WBAN. Through extensive simulation, we show the proposed MAC protocol can minimize the average packet latency for urgent data. Thus, when patients have an emergency situation, our MAC allows adequate assistance time and medical treatment for patients. The simulation based on NS-2 shows that our Hybrid Priority MAC has the good performance and usability.

An Adaptive Routing Protocol with a Balanced Energy Consumption For Wireless Ad-hoc Networks (애드혹 네트워크에서 에너지 소비 균형을 고려한 적응형 라우팅 프로토콜)

  • Kim, Yong-Hyun;Hong, Youn-Sik
    • The KIPS Transactions:PartC
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    • v.15C no.4
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    • pp.303-310
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    • 2008
  • To increase the lifetime of ad-hoc networks, a ratio of energy consumption for each node should be kept constant by equally distributing network traffic loads into all of the nodes. In this paper, we propose a modified AODV routing protocol to determine a possible route by considering a remaining battery capacity of a node and the degree of its usage. In addition, to reduce the amount of energy consumption during the path rediscovery process due to the huge amount of the AODV control messages the limited number of possible routes are stored into a routing table of a source node. When some links of a route fail, another possible path can be looked up in the table before the route discovery process should be initiated. We have tested our proposed method with a conventional AODV and a MMBCR method which is one of the power-efficient energy routing protocols based on the three performance metrics, i.e., the total remaining battery capacity, network lifetime and the ratio of data packets received by the destination node to compare their performance.

Stochastic Optimization of Multipath TCP for Energy Minimization and Network Stability over Heterogeneous Wireless Network

  • Arain, Zulfiqar Arain;Qiu, Xuesong;Zhong, Lujie;Wang, Mu;Chen, Xingyan;Xiong, Yongping;Nahida, Kiran;Xu, Changqiao
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.15 no.1
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    • pp.195-215
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    • 2021
  • Multipath Transport Control Protocol (MPTCP) is a transport layer protocol that enables multiple TCP connections across various paths. Due to path heterogeneity, it incurs more energy in a multipath wireless network. Recent work presents a set of approaches described in the literature to support systems for energy consumption in terms of their performance, objectives and address issues based on their design goals. The existing solutions mainly focused on the primary system model but did not discourse the overall system performance. Therefore, this paper capitalized a novel stochastically multipath scheduling scheme for data and path capacity variations. The scheduling problem formulated over MPTCP as a stochastic optimization, whose objective is to maximize the average throughput, avoid network congestion, and makes the system more stable with greater energy efficiency. To design an online algorithm that solves the formulated problem over the time slots by considering its mindrift-plus penalty form. The proposed solution was examined under extensive simulations to evaluate the anticipated stochastic optimized MPTCP (so-MPTCP) outcome and compared it with the base MPTCP and the energy-efficient MPTCP (eMPTCP) protocols. Simulation results justify the proposed algorithm's credibility by achieving remarkable improvements, higher throughput, reduced energy costs, and lower-end to end delay.

Design and Implementation of User Pattern based Standby Power Reduction System Applying Zigbee-MQTT in a Smart Building Environment (스마트빌딩 환경에서 Zigbee-MQTT를 이용한 사용자 패턴 기반 대기전력 저감 시스템 설계 및 구현)

  • Jang, Young-Hwan;Lee, Sang-Soon
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.24 no.9
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    • pp.1158-1164
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    • 2020
  • In Korea, the dependence on imported energy is very high, and research to reduce standby power is being conducted based on Zigbee, a low-power technology, to reduce wasted power and improve power efficiency. However, because Zigbee is not an IoT standard protocol and is not network-based, it is necessary to build a network with a separate gateway, and research on standby power is insufficient because the standards for international power consumption of devices are ambiguous. Therefore, in this paper, we applied the IoT standard protocol MQTT to the existing Zigbee technology to build a network network without a separate gateway, and designed and implemented a standby power reduction system that collects standby power degradation and user patterns. As a result of evaluating with the existing system, it was confirmed that about 7.11% of standby power was consumed compared to the existing system.

Design and Implementation of Ubiquitous Sensor Network System for Monitoring the Bio-information and Emergency of the Elderly in Silver Town

  • Choi, Seong-Ho;Park, Hyung-Kun;Yu, Yun-Seop
    • Journal of information and communication convergence engineering
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    • v.8 no.2
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    • pp.219-222
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    • 2010
  • An ubiquitous sensor network (USN) system to monitor the bio information and the emergency of the elderly in the silver town is presented. The USN system consists of the sensor node platforms based on MCU of Atmage128L and RF Chip of CC2420 satisfying IEEE 802.15.4, which includes the bios sensor module such as the electrocardiogram (ECG) sensor and the temperature sensor. Additionally, when an emergency of the elderly is occurred in the silver town, the routing algorithm suitable to find and inform the location of the elderly is proposed, and the proposed routing algorithm is applied to the USN. To collect and manage the ECG data at the PC connected to the sink node, LabView software is used. The bio information and the emergency of the elderly can also be monitored at the client PC by TCP/IP networks in the USN system.

An OS Platform Independent Architecture of Web-based Teleoperation for mobile robot

  • Ko, Deok-Hyeon;Lee, Soon-Geul
    • 제어로봇시스템학회:학술대회논문집
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    • 2004.08a
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    • pp.346-349
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    • 2004
  • The teleoperation system applies all of the industrial fields due to the development of the network infrastructure. It is one of the indispensable elements for controlling the robot at a remote sight and monitoring the limit or unknown environment. The common teleoperation robot system is what has the visual module to supply the network system and realistic UI to the existed robot system. Therefore, remarked that the fusion between modules and transmission of visual data the remarked the important element to improve the robot application in the various environments. Delay of development time by robot platform and noneffective communication among developers are also problem to approach. In this paper we propose the independent teleoperation system. The main application language is JAVA in this system, which is applied JAVA API like JNI and JMF to construct the effective teleoperation system. The system has the both side communication system between sever and client as a basic structure. The visual data that is attached the robot at a remote sight is captured by JMF API and then is transmitted to the web browser called client by RTR protocol. JNI is used to connect between JAVA and the lower part application (sensor fusion, motion control.) of the robot programmed by various Native languages. The proposed system is the application that can perform the elements, for instance transmission of visual data, the fusion of various native application modules and the effective network communication, with any platform.

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