• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.10
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• pp.106-114
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• 2020

It is very important for beginners in networking to build, test, and operate an IP network system, which is the key infrastructure of the fourth industrial revolution. An IP network system consists of the IP network itself, covering both the internet and underlying layers, plus the basic network system supporting fundamental network services, with a DNS, the DHCP, email, WWW, and application service systems, such as VoIP. This paper suggests an open software-based practice platform with a minimal network configuration on which beginners can practice on nearly all of the IP network system, and it presents a practice scenario and results. In addition, it adds both IP address allocation and routing table manipulation functions to the network simulator software, which will allow beginners to learn table-based datagram routing schemes in advance. This platform may be useful for networking beginners in order to practice on an IP network system on their own personal computers without additional equipment and costs.

• Proceedings of the KIEE Conference
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• 2004.11c
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• pp.206-208
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• 2004

A new method to control a remote robot with PDA and wireless network is presented. The needs of remote control systems using a home network environments are increased in these days. To solve the shortage of IP address in network, authorized TCP/IP and unauthorized TCP/IP address are used. The unauthorized TCP/IP is obtained by using MAC Address in the system and Network Layer. The model in the system is similar to Sever&Client in structure. Using this system, it is very easy to combine one network device with other network system. A robot system and PDA are used to show the effectiveness of the control system in home network environments.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.29 no.2B
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• pp.192-202
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• 2004

In this paper we have proposed policy-based network management system architecture for Internet QoS support Mobile IP networks that is divided into four layers(application layer, information management layer, policy control layer, device layer), then we propose an implementation strategy of policy-based network management system to enforce various control and network management operations and a model of policy server using SCOPS(Simple Common Open Policy Service) protocol that is developed in this research. For policy-based mobile IP network management system implementation, we have derived four policy classes(access control, mobile IP operation, QoS control, and network monitoring) and we showed operation procedures for each policy scenarios. Finally we have implemented Internet QoS support policy-based mobile IP network testbed and management system and verified out DiffServ policy enforcement behaviors for a target class service that is arranged a specific bandwidth on network congestion conditions.

• Journal of Industrial Technology
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• v.28 no.B
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• pp.245-250
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• 2008

Recently, mobile devices have supported wireless LAN as well as bluetooth, where the services such as heterogeneous network access and seamless mobility connection are important. Even though the mobility and physical network might be varied, an efficient communication mechanism for the network access and a robust mobility management of mobile devices are needed. In this paper, we design and implement a Bluetooth system with mobile LAN access capability. The proposed system has the following features; 1) IP connection is enabled by BENP in the link layer, 2) The networks devices of heterogeneous mobile devices are integrated into a single virtual network interface, 3) IP mobility between the bluetooth and wireless LAN is supported by mobile IP. The experimented results show that the packet loss and delay time during the handover duration is reduced by predicting the handover among different networks followed by the setup of any required parameters in advance.

• 한국정보통신설비학회:학술대회논문집
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• 2008.08a
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• pp.350-354
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• 2008

IP-based mobile communication system is one of the key research items in the mobile networks for a long time. But, due to some technical issues and no need of markets, it is still not full-fledged. Recently, CDMA and WCDMA service providers want to introduce IP-based network connectivity. Even though their efforts, the main network intra-structure depends on ATM or HDLC technology. This article describes a good example of commercialization of IP-based mobile communication systems. Our research is not experimental system but a in-service system - replacing the existing equipments with new IP-based systems. In this paper, we introduce IP related technologies used in our research such as IP-based ATCA(Advanced Telecommunications Computing Architecture) platform, HA(High Availability) redundancy, IP multicast, network redundancy techniques, multi-link bundling and IP header compression. These are already well-known to internet domain. We mix them with mobile communication systems concretely.

• Proceedings of the Korean Information Science Society Conference
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• 2002.10e
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• pp.76-78
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• 2002

Multicasting over mobile IP network becomes more important with the increasing needs of supporting multimedia services in mobile network. The IETF has suggested two approaches which are remote subscription and bidirectional tunneling for supporting mobility management in multicasting over mobile IP. But these protocols have problems - the frequent reconstruction of multicast delivery tree, packet less during handoff, convergence problem, and so on. In this paper, we propose to use preconfiguration of multicast delivery tree when mobile host enters the foreign network. It will decrease the frequency of multicast delivery tree reconstruction, and reduce the packet loss during handoff, Also the multicast delivery tree maintained by Keep Alive messages makes the signaling overload of networks diminished.

• Convergence Security Journal
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• v.10 no.3
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• pp.69-75
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• 2010

At present, deterioration in service quality, which caused by increased network traffic from a lot of users in the same network, makes smooth communication service difficult. In this paper, we present policy-based QoS management system for VoIP service in order to supply smooth VoIP service to users. The presented system can guarantee quality of VoIP service even in huge traffic situation, and makes it possible to operate whole network in an efficient manner.

• Proceedings of the KIEE Conference
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• 2006.10c
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• pp.175-177
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• 2006

This paper deals with implementation of middleware using CAN(Controller Area Network) network and TCP/IP for real-time distributed control system of a humanoid robot. Existent system using CAN network is available. But, there is problems in extensibility and flexibility. In this raper, the new system using TCP/IP for solution and improvement of problems is proposed. The new system is applied to ISHURO-II, real-humanoid robot. The performance is verified through experiment.

• Proceedings of the KIEE Conference
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• 2004.07d
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• pp.2386-2388
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• 2004

Recently, rapid process of network technology has an effect on the field of control engineering. And it gives effect to network control system(NCS) research that grafts existing control system and network has been studied. According to one-chip development of TCP/IP that is the most useful in LAN server for hardware, it can usefully and conveniently apply to network control system before. This paper construct network control system that can work close-loop control takes advantage of Ethernet that is the most for general data transmission network. Here, protocol uses for data transmission makes use for TCP/IP. This work the basic data transmitter-receive experiment to take advantage of network node was produced. And then, DC-motor can be control plant. Finally, I will prove to build speed control system of multiple DC-motor through Ethernet.

• Journal of the Institute of Convergence Signal Processing
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• v.12 no.2
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• pp.102-106
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• 2011

The transfer capability of HFC (Hybrid Fiber Coax) network is superior to xDSL. HFC network, however, is not suitable for transferring high quality video due to cable model interfaces. For the services of high quality IPIV or VOD, the extra exclusive downstream transfer system is required without upgrading pre-equipped cable modem and service capability. This paper is aimed to develop the extra exclusive downstream transfer system not changing existing cable modem system but providing same quality of services. This system is composed of the extra exclusive downstream IP-cable sender and modem. This sender and modem have 30 Mbps transfer capability and HDTV stream can be served in the Cable TV network using 21 Mbps HDTV transport stream.