• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.5 no.5
• /
• pp.959-975
• /
• 2011

Wireless mesh networks enlarge the wireless coverage area by interconnecting relatively stationary wireless routers (mesh routers). As wireless mesh networks are envisioned to provide high-bandwidth broadband Internet service to a large community of users, the Internet gateway, which acts as a central point of Internet attachment for the mesh networks, is likely to suffer heavily from the scramble for shared wireless resources because of aggregated traffic toward the Internet. It causes performance decrement on end-to-end transmissions. We propose a scheme to balance the load in a mesh network based on link quality variation to different Internet gateways. Moreover, under the mesh coverage, mobile nodes can move around and connect to nearby mesh routers while still keeping the connections to the Internet through the best gateway in terms of link quality. In this structure, gateways perform the balancing procedure through wired links. Information about gateways and mobile node's location is distributed appropriately so that every mesh router can quickly recognize the best gateway as well as the positions of mobile nodes. This distributed information assists mobile nodes to perform fast handoff. Significant benefits are shown by the performance analysis.

• Journal of Institute of Control, Robotics and Systems
• /
• v.7 no.4
• /
• pp.326-333
• /
• 2001

This paper focuses on a method to connect mobile devices such as mobile robot. Automated Guided Vehicle (AGV) and Unmanned Container Transporter(UCT) to a fieldbus. In this paper, the IEEE 802.11 wireless LAN is used to extend a Profibus network for the mobile devices. In order to integrate these two networks, a gateway is developed using two threads and an internal buffer. Furthermore, a polling algorithm is applied at the gateway in order to satisfy real-time requirements on data communication, Finally, the performance measures such as data latency and throughput are experimentally evaluated on a wirelessly-extended Profibus network. The results shows the feasibility of the wireless extension of Profilbus for various mobile device.

• Proceedings of the Korean Information Science Society Conference
• /
• 2004.10a
• /
• pp.364-366
• /
• 2004

현재의 VPN 제품들은 단말의 IP 이동성을 지원하지 못하고 있다. 단말의 이동 시 단말은 새로운 IP 주소를 할당받게 되는데, VPN 게이트웨이는 단말이 초기에 등록한 IP 정보만을 가지고 있기 때문에 이동한 단말이 전송하는 패킷을 폐기하게 된다. 본 논문에서는 VPN 세션의 단절 없이 단말의 이동성을 지원하는 VPN 게이트웨이를 설계하고 구현하였다. 본 논문에서 설계한 VPN 게이트웨이는 IPv6 기반 네트워크에서 동작하며, 단말의 이동성을 지원찰기 위해 Mobile IPv6 기술과 VPN 기술을 통합하는 구조를 갖는다.

• Proceedings of the Korean Information Science Society Conference
• /
• 2000.04a
• /
• pp.481-483
• /
• 2000

PCS, Digital Cellular, CDPD, 그리고 Handheld PC와 같은 휴대단말기를 사용해 각종 정보망의 서비스를 받으려면 움직임이 점차 커지고 있다. 이에 발 맞추어 일반 이동단말기에서 인터넷을 접속 할 수 있는 여러 기술들이 개발되었으며, 현재 사용하는 것으로 Unwired Planet 사가 개발한 HDML(Handheld Device Markup Language)기술이 있고, WAP Forum에서 제시한 WAP(Wireless Markup Language)가 있다. WAP의 구조에서 가장 핵심적인 요소로서 WAP Gateway가 있으며, 현재까지 WAP Gateway에 대한 특별한 표준화가 이루어지지 않은 단계에서 각 컨텐츠 사업자가 WAP Gateway를 나름대로 구현하고 사용하는 실정이다. 본고는 보다 확장성을 가지고 무선이라는 환경에 적합하도록 서비스를 개선할 수 있는 WAP Gateway의 설계 및 구현 이슈에 대하여 다룬다.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2015.05a
• /
• pp.895-896
• /
• 2015

With the development of sensor, wireless mobile communication, embedded system and cloud computing, the technologies of Internet of Things have been widely used in logistics, Smart devices security, intelligent building and o on. Bridging between wireless sensor networks with traditional communication networks or Internet, IoT gateway plays n important role in IoT applications, which facilitates the integration of wireless sensor networks and mobile communication networks or Internet, and the management and control with wireless sensor networks. The IoT Gateway is a key component in IoT application systems but It has lot of security issues. We analyzed the trends of security and privacy matters.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2015.10a
• /
• pp.1025-1026
• /
• 2015

With the development of sensor, wireless mobile communication, embedded system and cloud computing, the technologies of Internet of Things have been widely used in real word. Connecting wireless sensor networks with traditional communication networks or Internet, IoT gateway plays an important role in IoT applications. It facilitates the integration of wireless sensor networks and mobile communication networks or Internet. The IoT gateway is a key component in IoT application systems. But It has lot of security issues. We analyzed the issues of security and privacy.

• Journal of Information Processing Systems
• /
• v.12 no.2
• /
• pp.196-213
• /
• 2016

System Architecture Evolution (SAE) with Long Term Evolution (LTE) has been used as the key technology for the next generation mobile networks. To support mobility in the LTE/SAE-based mobile networks, the Proxy Mobile IPv6 (PMIP), in which the Mobile Access Gateway (MAG) of the PMIP is deployed at the Serving Gateway (S-GW) of LTE/SAE and the Local Mobility Anchor (LMA) of PMIP is employed at the PDN Gateway (P-GW) of LTE/SAE, is being considered. In the meantime, the Host Identity Protocol (HIP) and the Locator Identifier Separation Protocol (LISP) have recently been proposed with the identifier-locator separation principle, and they can be used for mobility management over the global-scale networks. In this paper, we discuss how to provide the inter-domain mobility management over PMIP-based LTE/SAE networks by investigating three possible scenarios: mobile IP with PMIP (denoted by MIP-PMIP-LTE/SAE), HIP with PMIP (denoted by HIP-PMIP-LTE/SAE), and LISP with PMIP (denoted by LISP-PMIP-LTE/SAE). For performance analysis of the candidate inter-domain mobility management schemes, we analyzed the traffic overhead at a central agent and the total transmission delay required for control and data packet delivery. From the numerical results, we can see that HIP-PMIP-LTE/SAE and LISP-PMIP-LTE/SAE are preferred to MIP-PMIP-LTE/SAE in terms of traffic overhead; whereas, LISP-PMIP-LTE/SAE is preferred to HIP-PMIP-LTE/SAE and MIP-PMIP-LTE/SAE in the viewpoint of total transmission delay.

• 한국ITS학회:학술대회논문집
• /
• 2003.11a
• /
• pp.165-168
• /
• 2003

• Journal of the Institute of Electronics Engineers of Korea TC
• /
• v.43 no.11 s.353
• /
• pp.168-174
• /
• 2006

In this paper, we propose an architecture for communication between the IPv4-based UA and the IPv6-based UA in IMS based Mobile Networks, and design and implement the IMS protocol Translator for verification of the architecture. For the design of the internetworking between the IPv4 and the IPv6, we analyze the transition mechanisms and investigate the protocol translator. The IMS protocol translator is composed of the IMS-ALG(IP Multimedia Subsystem - Application Level Gateway) and TrGW(Translation Gateway), and the conformance of these components are verified by experiments.

• Proceedings of the Korean Society of Computer Information Conference
• /
• 2013.01a
• /
• pp.283-285
• /
• 2013

본 논문에서는 헬스케어 시스템 제공업체와 소비자 모두 스마트폰 헬스케어를 향상시킬 도구로 수용할 수 있고 ISO/IEEE11073, HL7 표준을 적용한 홈 헬스케어 시스템을 제안하고자 한다. 이 시스템은 표준 기반의 홈 헬스케어 게이트웨이 플랫폼의 중요성이 부각되는 홈 헬스케어에서 건강측정을 위하여 가장 많이 사용되는 혈당계, 혈압계, 심박측정계, 산소포화도 측정계, 심전도 측정계 등의 홈 헬스케어 의료기기를 제안하였다. 아울러, 표준 핵심 기술 요소인 ISO/IEEE 11073, HL7을 준용하는 게이트웨이 플랫폼을 스마트폰에 적용하여 PMG(personal mobile gateway) 기반의 홈&모바일 헬스케어 시스템이다.