• Journal of Digital Convergence
• /
• v.17 no.9
• /
• pp.161-171
• /
• 2019

Government transactions over wireless electronic devices are not safe and hence the messages are prone to attack. Thereby, devices supporting wireless Internet must assure the same level of security and privacy as the wired network. National public key infrastructure (NPKI) for electronic government used in the wired environment is not suitable for wireless environment for mobile government (mGovernment) because of the limitations of computing power, memory capacity and restricted battery power. This requires the development of a new NPKI for mGovernment, denoted as mNPKI, to developing countries, which provides the same security level as the wired NPKI. For the wireless environment requirements, mNPKI is based on short lived certificates. Analysis shows that mNPKI is well suited to wireless Internet and provides the same security requirement from the wired NPKI.

• Journal of Institute of Control, Robotics and Systems
• /
• v.6 no.8
• /
• pp.652-658
• /
• 2000

Wired and wireless communication technique is growing rapidly. As the number of communication users is larger problems such as network congestion and signal interference between users are getting most important, There have been researches that try to solve them by control theoretic approaches. They apply various control theories to the control issues of communication. this paper surveys these researches and classifies them into ATM TCP/IP and wireless communication according to the target. The feedback control model of each communication protocol is shown and related researches are summarized and analyzed.

• Journal of the Korean Society for Precision Engineering
• /
• v.25 no.2
• /
• pp.115-122
• /
• 2008

Mostly used sensors have wired powering and two-way cable systems. It is difficult to employ wired sensor network in ubiquitous era because of a number of sensors and cables. Therefore, sensor networks move from wired systems to wireless systems for the future. However, the power source is a critical obstacle for wireless sensornodes. This research represents the new power source which supplies energy sensor node, maintains over 10 years, and thus replaces batteries with limit of lifetime. The system with piezo materials scavenges extra energies such as vibration and acceleration from the environment. Then it converts the scavenged mechanical energy to electrical energy for powering a sensor, a controller and a circuit for regulating voltage and transmitting sensor value. This study explains the properties of piezo material through theoretical analysis and experiments, and demonstrates powering sensor and transmitting data with stored energy (35mJ) for 14 sec. The developed system provides a solution to overcome the critical problem of making up wireless sensor networks.

• Journal of IKEEE
• /
• v.11 no.4
• /
• pp.227-234
• /
• 2007

In this paper, to support a QoS level appropriate to the user in Wireless Home Network based Wireless LAN, we propose a QoS support architecture which includes Wired Network and Wireless Network. Actually, an important problem to support QoS in Wireless Home Network is approached not only on a MAC level in Wireless LAN but also on a integrated method to combine Network layer with Datalink layer. By applying the integrated QoS support method, it is possible to provide QoS support architecture using a Wireless LAN terminal with a minimum changing, and the proposed scheme has advantage of QoS support method, which is more superior than a existing scheme to support QoS in MAC level of Wireless LAN. Simulations results show that overall performance of the proposed scheme can be improved.

• The Journal of the Korea Contents Association
• /
• v.8 no.6
• /
• pp.54-65
• /
• 2008

When DDoS attack is achieved, malicious host discovering is more difficult on wireless network than existing wired network environment. Specially, because wireless network is weak on wireless user authentication attack and packet spoofing attack, advanced technology should be studied in reply. Integrated Access Device (IAD) that support VoIP communication facility etc with wireless routing function recently is developed and is distributed widely. IAD is alternating facility that is offered in existent AP. Therefore, advanced traffic classification function and real time attack detection function should be offered in IAD on wireless network environment. System that is presented in this research collects client information of wireless network that connect to IAD using AirSensor. And proposed mechanism also offers function that collects the wireless client's attack packet to monitoring its legality. Also the proposed mechanism classifies and detect the attack packet with W-TMS system that was received to IAD. As a result, it was possible for us to use IAD on wireless network service stably.

• Journal of the Korean Institute of Telematics and Electronics S
• /
• v.35S no.1
• /
• pp.39-51
• /
• 1998

In this paper, we propose signaling procedures amon network elements for a connection rerouting method which can reduce inter-switch handoff processing delay reduces the delay in the connection re-routing by reserving VPI/VCIs for possible inter-switch handoff calls in advance. Additionally, we mathematically analyze the signaling procedures and then suggest solutions to the relations with cluser size, network topoloty, handoff-request rete and handoff delay. With simulation, the solutions are validated. From numerical examples, we concluded taht handoff delay, one of the handoff QoSs, can be satisfied by adjusting the cluster size and network topology according to the handoff -request rate of service area. With our proposed signaling and analytic methods, we concluded that the connection rerouting method using cluster-sectoring effectively reduces the delay of inter-switch handoff processing than dynamic connection rerouting method. Our solutions are useful in guaranteeing the requested handoff delay (especially, inter-switch handoff delay) when the connection rerouting method is applied to ATM-based wireless/wired integrated network.

• Journal of IKEEE
• /
• v.12 no.1
• /
• pp.18-26
• /
• 2008

With the advent of Ubiquitous environment, wired-wireless combination network is being studied very actively in which mobile nodes having multi-hop communication capability connect wired internet network easily, and shares the information. The study of wired and wireless combination network between MANET(Mobile Ad Hoc Network) and wired network is being focused only on the configuration of heterogeneous network interface. The proposed algorithm establishes independent multi-paths between source node and destination node to prevent data loss when errors happen in route. As the result, it shows that the reliability of the combination network can be improved by making data transmit continuously on the route error.

• Proceedings of the IEEK Conference
• /
• 2001.06a
• /
• pp.149-152
• /
• 2001

In general, the wireless services based on markup language and provided with wired network requires dedicated gateway system. But in this case, the serious problems such as security vulnerabilities, damage of contents are occurred to the application. In this paper, to improve above problems, we designed and implemented the new application named "Interacted Wired St Wireless Student Information System" using J2ME(Java 2 Micro Edition) platform and XML(eXtensible Markup Language) to transmit user data safely and support the system extendibility maintaining data format consistency respectively.pectively.

• Convergence Security Journal
• /
• v.11 no.1
• /
• pp.11-18
• /
• 2011

Wireless mesh network technology with transmission speeds similar to wired and wireless technology means to build, compared with wired networks, building a more efficient network to provide convenience and flexibility. The wireless mesh network router nodes in the energy impact of the mobility is less constrained and has fewer features entail. However, the characteristics of various kinds due to network configuration settings and the choice of multiple paths that can occur when the system overhead and there are many details that must be considered. Therefore, according to the characteristics of these network routing technology that is reflected in the design and optimization of the network is worth noting. In this paper, a multi-path setting can be raised in order to respond effectively to the problem of the router node data loss and bandwidth according to traffic conditions and links to elements of the hop count evaluation by using a genetic algorithm as a workaround for dynamic routing the routing metric for wireless mesh network scheme is proposed.

• Proceedings of the KSR Conference
• /
• 2006.11b
• /
• pp.689-694
• /
• 2006

Wireless LAN is getting more popularity and plays a main role in electronic and telecommunication field. Wireless LAN is more convenient than wired LAN when mobility is required, and are sometimes the only feasible choice. Wireless LAN can also pose a significant security risk when not properly installed and maintained. Thus, this paper studies real-time message transmission using existing mobile telecommunication network and describes considerations and procedures when introducing wireless LAN concept and wireless LAN systems. It also studies integrated wired and wireless networking including wireless LAN bridge and AP technology of International Organization for Standardization, and especially real-time dynamic image data transmission in a moving train.