• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.9 no.7
• /
• pp.2354-2370
• /
• 2015

The advantages of employing SCTP-based Concurrent Multipath Transfer (CMT) have been demonstrated to be very useful for data delivery over multi-homed wireless networks. However, there is still significant ongoing work addressing some remaining limitations and challenges. The most important concern when applying CMT to data delivery is related to handling packet reordering and buffer blocking. Another concern on this topic is that current sender-based CMT solutions seldom consider balancing the overhead and sharing the load between the sender and receiver. This paper proposes a novel Receiver-driven Cooperation-based Concurrent Multipath Transfer solution (CMT-Rev) with the following aims: (i) to balance overhead and share load between the sender and receiver, by moving some functions including congestion and flow control from the sender onto receiver; (ii) to mitigate the data reordering and buffer blocking problems, by using an adaptive receiver-cooperative path aggregation model, (iii) to adaptively transmit packets over multiple paths according to their receiver-inspired sending rate values, by employing a new receiver-aware data distribution scheduler. Simulation results show that CMT-Rev outperforms the existing CMT solutions in terms of data delivery performance.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
• /
• v.19 no.2
• /
• pp.107-113
• /
• 2005

In this paper, Web server is built up using PXA255, 32bit RISC processor with porting Embedded Linux and GoAhead HTTP(Hyper Text Transfer Protocol) web server, and the system which can monitor and control the environment and condition for AICC(Automatic Intelligent Cruise Control) is realized For sensing the operation condition and change of vehicle the desired data is derived by interfacing ECU(Electric Control Unit) and Embedded system and the rpm of engine is controlled by step motor connected to throttle valve.

• The Journal of Information Technology and Database
• /
• v.7 no.1
• /
• pp.67-82
• /
• 2000

In this paper we have developed a message transfer protocol, CMP, which improves MSP's message processing capability. The proposed method has taken into account document classification to improve the efficiency of message processing. The difference between the conventional MSP and CMP has been addressed. The CMP's performance has been shown by various experiments including number, alphabet, Korean letter, Chinese letter, music sound and compression file transmission. And security capability of both protocols has been compared based on the specification of FIPS 140-2. The CMP's overall performance is shown to be superior to that of MSP on the processing speed in the performance perspective and on the function of cryptographic module interface and cryptographic key management in the security perspective respectively.

• Journal of the Semiconductor & Display Technology
• /
• v.23 no.1
• /
• pp.65-70
• /
• 2024

Direct cache-to-cache transfer has been studied to reduce the latency and bandwidth consumption related to the shared data in multiprocessor system. Even though these studies lead to meaningful results, they assume that caches consist of SRAM. For example, if the system employs the non-volatile memory, the one of the most important parts to consider is to decrease the number of write operations. This paper proposes a hybrid write avoidance cache coherence protocol that considers the hybrid cache architecture. A new state is added to finely control what is stored in the non-volatile memory area, and experimental results showed that the number of writes was reduced by about 36% compared to the existing schemes.

• Journal of radiological science and technology
• /
• v.24 no.2
• /
• pp.71-75
• /
• 2001

As the adoption of PACS and hospital information system among university hospitals and hospital level institutions grows bigger, the need of sharing and transferring medical information among medical institutions is rising. For the medical information, which is saved in the hospital medical system, to be transferred within the same hospital, domestic, or foreign medical institutions, a standard protocol is necessary. But realistically, most of the domestic hospitals do not abide by H7L which is the HIS standard and so, information transferring is not possible as of present. As such, the purpose of this research is to implement the information between HIS and PACS to an international standard by constructing HL7 messages through HL7 Interface. which will eventually make possible information transferring between different hospitals. Our research team has developed a method which will make the PACS equip hospitals that do not follow HL7 standard which will make possible to transfer information between HIS and PACS through HL7 Message. By constructing message files, which follow the form of HL7 Message in the HL7 Interface, they can be transferred to PACS through the ftp protocol. The realization of the HIS/OCS Interface through HL7 enables data transferring between domestic and foreign medical institutions possible by implementing the international standard in the PACS and HIS data transferring process. The HL7 that our research team has developed made patient data transfer between medical institutions possible. The Interface is for a specific system model and in order for the data transfer between different systems to be realized, interfaces that are fit for each system must be needed. If the interface is improvised and implemented to each hospital's information system, the data sharing among medical institutions can be broadened.

• Proceedings of the Korea Database Society Conference
• /
• 2000.11a
• /
• pp.280-286
• /
• 2000

본 논문에서는 기존의 비대화형 전송 프로토콜을 기반으로 하여 비밀정보교환을 위한 여러 가지 부가기능을 가지는 새로운 비대화형 전송 프로토콜을 설계 제안한다. 제안한 방식은 기존의 프로토콜의 구조를 그대로 따르면서 Bit Commitment 기법을 적용한 형태로서 여러가지 안전한 기능을 가진다. 본 논문에서 제안한 기법은 서로 신뢰하지 못하는 두 당사자 사이에서 비밀 정보를 교환하고자 하는 분야에 있어서 보다 안전한 프로토콜로서 활용될 수 있다.

• The Journal of the Korea Contents Association
• /
• v.11 no.2
• /
• pp.69-78
• /
• 2011

Recently, the bandwidth available to an end user has been dramatically increasing with the advancing of network technologies. This high-speed network naturally requires faster and/or stable data transmission techniques. The UDT(UDP based Data Transfer protocol) is a UDP based transport protocol, and shows more efficient throughput than TCP in the long RTT environment, with benefit of rate control for a SYN time. With a NAK event, however, it is difficult to expect an optimum performance due to the increase of fixed sendInterval and the flow control based on the previous RTT. This paper proposes a rate control method on following a NAK, by adjusting the sendInterval according to some degree of RTT period which calculated from a set of experimental results. In addition, it suggests an improved flow control method based on the TCP vegas, in order to predict the network congestion afterward. An experimental results show that the revised flow control method improves UDT's throughput about 20Mbps. With combining the rate control and flow control proposed, the UDT throughput can be improved up to 26Mbps in average.

• Proceedings of the KIEE Conference
• /
• 1998.07g
• /
• pp.2373-2376
• /
• 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.

• The Journal of the Korea Contents Association
• /
• v.7 no.11
• /
• pp.111-119
• /
• 2007

Sensor networks are needed for special purposes such as collecting or transmitting information by using sensor devices, for which various routing protocols have been proposed. Among existing protocols, the modified PEGASIS routing technique is known to be effective when applied to cases with directional transmissions of data. However it does not consider recovery from errors or guaranteeing stability in data transmission, while sensor devices performing repetitive relays and controls are prone to errors. In this paper, a double relay routing protocol for Zigbee based sensor networks where data are transfered reliably with a linear direction. The proposed protocol is effective in the sense that it secures the relaible transmission of data with minimal energy consumption based on a directional data transfer. A streetlight control system has been presented as an application of the proposed protocol.

• Journal of the Institute of Electronics Engineers of Korea TC
• /
• v.46 no.1
• /
• pp.64-71
• /
• 2009

TETRA system has been developed focusing on the supporting high-speed and high-capacity data transfer and improving the wireless technology. Hence, TETRA over IP technology became the important basis for supporting compability with various network wireless technologies and high-speed data transfer technologies. For advancing the current TETRA system based on IPv4 network, introduction of IPv6 protocol is necessary. In this paper, we propose an optimized scheme to support IP mobility to IPv6 node when IPv6 protocol is applied to the enviroment ingreated WLAN and TETRA networks. We proposed two scheme using MIPv6 protocol and HMIPv6 protocol respectively. Then, we evaluate performance of the proposed schemes and anlayze the results in order to derive the optimized scheme for the environment integrated WLAN and TETRA networks.