• IEMEK Journal of Embedded Systems and Applications
• /
• v.10 no.1
• /
• pp.25-31
• /
• 2015

The quality of medical treatment can be promoted by transmitting high-definition medical images and sharing these images. The high speed transmission network is a requirement for the ultra high-definition media. A high quality medical research and education can be provided by connecting resources and media-data through the superhigh speed research network. Network bandwidth for 4K media transmission generated with Lambda network technology.

• 제어로봇시스템학회:학술대회논문집
• /
• 2005.06a
• /
• pp.1558-1562
• /
• 2005

This paper describes the design and implementation of a wireless home network system using Home Network Control Protocol (HNCP) called the wireless HNCP home network system. For wireless interfaces of HNCP, IEEE 802.11b and IEEE 802.15.4 standard protocols are considered. With the implementation of the wireless HNCP home network system, a simple analysis about coexistence between IEEE 802.11b and IEEE 802.15.4 is achieved. Through the implemented wireless HNCP home network system and the analytical results about the coexistence between both two different wireless protocols, the feasibility of the wireless HNCP home network system is shown.

• Current Optics and Photonics
• /
• v.4 no.4
• /
• pp.310-316
• /
• 2020

We propose and experimentally demonstrate an all-optical radio frequency (RF) spectrum broadening system based on time compression. By utilizing the procedure of dispersion compensation values, the frequency domain is broadened by compressing the linear chirp optical pulse which has been multiplexed by the radio frequency. A detailed mathematical description elucidates that the time compression is a very preferred scheme for spectrum broadening. We also report experimental results to prove this method, magnification factor at 2.7, 8 and 11 have been tested with different dispersion values of fiber, the experimental results agree well with the theoretical results. The proposed system is flexible and the magnification factor is determined by the dispersion values, the proposed scheme is a linear system. In addition, the influence of key parameters, for instance optical bandwidth and the sideband suppression ratio (SSR), are discussed. Magnification factor 11 of the proposed system is demonstrated.

• Journal of the Optical Society of Korea
• /
• v.19 no.4
• /
• pp.340-345
• /
• 2015

The Internet traffic is forecasted to grow at a compound annual rate of 21 % from 2013 to 2018, according to surveys carried out by Cisco [1]. Network resources are significantly over-provisioned in today's networks, and it is quite common to see link utilization in the 30-40% range [2]. Additionally, the multi-media services have widely divergent bandwidth and Quality of Experience (QoE) requirements. Unfortunately, the huge transmission capacity will increase the power consumption of network equipment [3]. Applications Coordinated with Transport, Internet Protocol and Optical Networks (ACTION) [4] has been proposed to realize a multi-QoE, application-centric, and highly energy-efficient network that leverages flexible elastic optical network technologies [5-7]. This paper provides key network technologies for realizing the ACTION, which are a virtual optical slice core network and a Time Division Multiplexing (TDM)-based deterministic active optical access network.

• Journal of KIISE:Computer Systems and Theory
• /
• v.30 no.3_4
• /
• pp.160-167
• /
• 2003

A static shuffle-exchange network is not only useful for several parallel applications but also use less hardware than the popular multi-stage network or hypercube. Even though it has a lot of advantages, it has never been used in any implemented parallel machine. One of the reasons is there has not been any techniques to make the network fault-tolerant. In this paper multiple fault-tolerant static shuffle-exchange networks are presented. In order to recover from k faulty processing elements, a network needs at least 2 k additional processing elements and at most 4 k additional shuffle ports for each processing elements. By decomposing the k fault-tolerant static shuffle-exchange network into m identical modules, this paper shows that the reliability of the network can be increased.

• Proceedings of the Korea Information Processing Society Conference
• /
• 2003.05b
• /
• pp.1241-1244
• /
• 2003

Diffserv Network의 혼잡 상태에서도 최소 전송속도를 보장하는 AF(Assured Forwarding)은 AF1부터 AF4에 이르기까지 다양한 Class 형태로 존재한다. Core Router나 Edge Router에서 패킷을 Drop 해야 한다면, 처음으로 DE(Default Forwarding) 방식의 패킷이 Drop되고, 피 다음으로 AE4, AF3, AF2, AF1의 등급을 가진 패킷들이 Drop 된다. 이러한 AF 패킷의 전송에서 A Network는 AF1, AE2, AF3, AF4의 순서로 패킷의 우선 순위를 두고, B Network는 그 반대인 AF4, AF3, AF2, AF1의 순서로 패킷의 우선 순위를 둔다면, A Network에서 최고의 품질을 제공받는 AF1 패킷이 B Network로 넘어가면서 가장 낮은 우선 순위의 서비스 품질을 제공받게 되어, B Network에서 패킷 드롭의 상황이 발생하게 되어 가장 먼저 드롭이 일어나게 된다. 이러한 결과는 반대로 B Network에서 A Network로 패킷을 보내는 과정에서도 발생한다. 본 논문은 이러한 AF Class의 패킷을 다른 정책을 가지는 네트워크로 전송할 때 AF 패킷 등급의 손실을 최소화하는 방안을 제시한다.

• JSTS:Journal of Semiconductor Technology and Science
• /
• v.4 no.4
• /
• pp.258-262
• /
• 2004

Storage over Ethernet (SoE) is a network storage architecture that allows direct attachment of existing ATA/ATAPI devices to Ethernet without a separate server. Unlike SAN, no server computer intervenes between the storage and the client hosts. We propose a SoE disk controller (SoEDC) amenable to low-cost, single-chip implementation that processes a simplified L3/L4 protocol and converts commands between Ethernet and ATA/ATAPI, while the rest of the complex tasks are performed by the remote hosts. Thanks to simple architecture and protocol, the SoEDC implemented on a single $4mm{\times}4mm$ chip in 0.18um CMOS technology achieves maximum throughput of 55MB/s on Gigabit Ethernet, which is comparable to that of a high-performance disk storage locally attached to a host computer.

• Journal of Sensor Science and Technology
• /
• v.16 no.4
• /
• pp.247-253
• /
• 2007

Low power consumption sensor network platform (sensor node) for sensor networking with IEEE 802.15.4 protocol was fabricated. The sensor node used ceramic bar type antenna for increasing RF signal performance and decreasing PCB size occupied by antenna. The communication range of the fabricated sensor node was about $20{\sim}30$ m in open environment with 915 MHz frequency bandwidth and well supported by Tiny OS. The sensor node have good connectivity with various external devices by RS-232, I2C, analogue and digital expansion board, hence, this sensor node can be applied to various applications in wireless sensor network and ubiquitous sensor network.

• Journal of Broadcast Engineering
• /
• v.25 no.5
• /
• pp.789-797
• /
• 2020

In this paper, we propose a protocol structure of a portable 4K Ultra High Definition (UHD) broadcast relay device that utilizes a 5G mobile communication network as a transport channel, and construct a prototype to conduct a broadcast relay performance test through a 5G mobile communication network. The test shows that the encoding time of the 4K UHD encoder is from a minimum of 86.28ms to a maximum of 88.41ms, the relay delay time in the 5G mobile communication network is 13.645ms on average, the delay variation is 17.49ms, and the glass-to-glass delay time is 289.90 on average, the delay variation is 27.63ms. Using the developed prototype, a relay test between Seoul and Anseong is conducted, and the possibility of 4K UHD broadcasting through a 5G mobile communication network is confirmed.

• Journal of the Korea Institute of Military Science and Technology
• /
• v.18 no.4
• /
• pp.423-431
• /
• 2015

A leased line modem usability was evaluated and investigated in the wireless internet protocol(IP) network. The signal of the modem in the circuit switching network was translated to IP packet by using several voice codecs (PCM, G.711A, $G.711{\mu}$, and etc.) and transmitted through the wireless IP network. The wireless IP network was simulated by the Tactical information and communication network Modeling and simulation Software(TMS). The performance and usability of the leased line modem are simulated using the system-in-the-loop(SITL) function of TMS with respect to packet delay, jitter, packet discard ratio, codecs, and wireless link BER.