• Title/Summary/Keyword: variable communication protocol

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A study on implementation of MAP-MMS protocol (MAP-MMS 프로토콜의 구현에 관한 연구)

  • 고우곤;강문식;박민용;이상배
    • 제어로봇시스템학회:학술대회논문집
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    • 1989.10a
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    • pp.520-523
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    • 1989
  • MAP(Manufacturing Automation Protocol), Network Protocol for FA has 7 Layer Structure of OSI. Being an Application Layer Protocol for Communication Interfaced with the Actual Programmable Devices, MMS(Manufacturing Message Specification) Consists of Three Factors of Services, Interfaces, and Protocol. For Details, It Classifies with the Followings ; Connection/Context Management, Remote Variable Access, Semaphore Management, File transfer and Management, Program UP/DOWN Load, Remote Program Fxecution. In this Paper Designing MAP Network Station of Programmable Device, we Analyze the Protocol of MMS, and Realize the State Diagram of each Services and Propose the Model of MMS Function Call Instructions.

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Flow Control Throughput Performance Improvement of Adaptive Packet Length Allocation Scheme in Wireless Data Communication System (무선 데이타 통신 시스템에서 적응패킷길이할당방식을 이용한 흐름제어 기능 개선)

  • 정기호;박종영;금홍식;이상곤;류흥균
    • Journal of the Korean Institute of Telematics and Electronics A
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    • v.32A no.2
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    • pp.11-18
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    • 1995
  • Error detection in ARQ(Automatic Repeat Request) protocols is very important in wireless data communication systems. The throughput efficiency of ARQ protocols can be improved by dynamically adapting the protocol packet length so that it approaches the optimum value for throuhput efficiency. In this paper, a simple and novel adaptive packet length allocation method is proposed which transmits the packets with variable length by dyanmically estimating the channel codition. The simulation results show that the average of throughput is improved by 315.4% in the stop-and-wait protocol, 41.4% in the go-back-N protocol and 155.9% in the selective repeat protocol respectively. And the throughput performances of adaptive packet length allocation method approximately approach the theoritically optimal throughput performances.

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Modeling & Performance Analysis of the MAC Protocol for VDL in the Aeronautical Mobile Communication System (항공이동통신 시스템에서 VDL을 위한 MAC 프로토콜 모델링 및 성능 분석)

  • Kim, Yong-Joong;Park, Hyo-Dal
    • Journal of Advanced Navigation Technology
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    • v.13 no.3
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    • pp.327-336
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    • 2009
  • This paper analysis the STDMA protocol in aviation wireless data communications and carry out the performance analysis with simulation. The STDMA protocol that is currently being used in VDL Mode-4 has TDMA system characteristics, which provides time-division into several slots per one frame. The results of modeled STDMA protocol's data channel analysis show approximate 0.7 channel throughput at the transmission probabilities 0.045, 0.2, and 0.3 in the aspects of channel throughput. The delay time are 2.32434sec, 2.0293sec, and 2.12128sec respectively. These results shows the good stability in spite of variable transmission probabilities. Consequently, it is expected that STDMA protocol would be used properly for domestic communication demands and supervision system improvement by means of applying this to point-to-point communication and data/location broadcasting as a fundamental technology in CNS/ATM.

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IMT-2000 Packet Data Processing Method utilizing MPLS (MPLS망을 적용한 IMT2000 시스템에서의 패킷 데이터 처리 절차)

  • Yu, Jae-Pil;Kim, Gi-Cheon;Lee, Yun-Ju
    • The Transactions of the Korea Information Processing Society
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    • v.6 no.11S
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    • pp.3190-3198
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    • 1999
  • Because of the rapid growth of the mobile communication, the need for the mobile internet access has grown up as well. since the current mobile communication network, however, is optimized for a voice communication system, which exclusively occupies a channel for a given time, it is not suitable for variable rate packet data. In order to support the mobile internet access, it is essential do design a reasonable packet switching network which supports the mobility. Since mobile packet network has longer latency, high speed switching and QoS are required to meet the user's requirements. In this paper, we suggest an resonable way to construct a network and its operation procedures utilizing GPRS(General Packet Radio Service) network and MPLS(Multi Protocol Label Switching) to provide a high speed switching and QoS mobile internet access. GPRS is used as a network which supports the mobility and MPLS guarantees the QoS and high speed IP protocol transmission based on the ATM switching technology.

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A Study on the VCR Cryptographic System Design Adapted in Wire/Wireless Network Environments (유무선 네트워크 환경에 적합한 VCR 암호시스템 설계에 관한 연구)

  • Lee, Seon-Keun
    • Journal of the Korea Society of Computer and Information
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    • v.14 no.7
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    • pp.65-72
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    • 2009
  • This paper proposed VCR cryptographic algorithm that adapted in TCP/IP protocol architecture and wire/wireless communication network environments. we implemented by hardware chip level because proposed VCR cryptographic algorithm perform scalable & reconfigurable operations into the security system. Proposed VCR cryptographic algorithm strengthens security vulnerability of TCP/IP protocol and is very profitable real-time processing and encipherment of high-capacity data and multi-user communication because there is important purpose to keep security about many user as that have variable round numbers function in network environments.

Synchronous Reservation Protocol for Variable-sized Messages in a WDM-based Local Network (WDM 망에서 가변 길이의 메시지 전송을 위한 동기 예약 프로토콜)

  • Lee, Jae-Hwoon;Rim, Min-Joong
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.38 no.6
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    • pp.1-10
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    • 2001
  • In this paper, we propose a synchronous reservation protocol that is efficient for supporting variable sized messages in a wavelength division multiplexing (WDM) based local network using a passive star topology. A. control channel is used to coordinate transmission on data channels. Time is slotted with fixed-sized slots. The network can accommodate a variable number of nodes, and can operate independently of the change of the number of nodes. So, any 'new' node can join the network anytime without network re-initialization. Moreover, with the protocol, we can avoid data channel and destination conflicts. We analyze the performance by using EPA method according to the variation of the end to end propagation delay with respect to one slot time, and validate the results by simulation.

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Building Light Weight CORBA Based Middleware for the CAN Bus Systems

  • Hong, Seongsoo
    • Transactions on Control, Automation and Systems Engineering
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    • v.3 no.3
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    • pp.181-189
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    • 2001
  • The software components of embedded control systems get extremely complex as they are designed into distributed systems get extremely complex as they are designed into distributed systems consisting of a large number of inexpensive microcontrollers interconnected by low-bandwidth real-time networks such as the controller area network (CAN). While recently emerging middleware technologies such as CORBA and DCOM address the complexity of distributed programming, they cannot be directly applied to distributed control system design due to their excessive resource demand and inadequate communication models. In this paper, we propose a CORBA-based middleware design for CAN-based distributed embedded control systems. Our design goal is to minimize its resource need and make it support group communication without losing the IDL (interface definition language) level compliance to the OMG standards. To achieve this, we develop a transport protocol on the CAN and a group communication scheme based on the well-known publisher/subscriber model. The protocol effectively realizes subject-based addressing and supports anonymous publisher/subscriber communication. We also customize the method invocation and message passing protocol, referred to as the general inter-ORB protocol (GIOP), of CORBA so that CORBA method invocations are efficiently serviced on a low-bandwidth network such as the CAN. This customization includes packed data encoding and variable-length integer encoding for compact representation of IDL data types. We have implemented our CORBA-based middleware on the mArx real-time operating system we have developed at Seoul National University. Our experiments clearly demonstrate that it is feasible to use CORBA in developing distributed embedded control systems possessing severe resource limitations. Our design clearly demonstrates that it is feasible to use a CORBA-based middleware in developing distributed embedded systems on real-time networks possessing severe resource limitations.

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Delay-Optimized Adaptive Multichannel Backoff Mechanism for VANET (VANET을 위한 지연 최적화 적응적 멀티 채널 백오프 메카니즘)

  • Lee, Jung-Jae
    • The Journal of the Korea institute of electronic communication sciences
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    • v.14 no.5
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    • pp.837-844
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    • 2019
  • In this paper, we propose the AMBM(: Adaptive Multi-channel Backoff Machisum) -Mac protocol to provide high throughput for non-safety applications in VANET(: Vehicular Ad Hoc Networks) environment. The proposed protocol guarantees the quality of service of non-safety packets by dynamically adjusting CW(: Channel Window) of WSA(: WAVE Service Advertisement) to maximize throughput between non-safety packets of different priority. It also shows that allocating a large amount of time for channel coordination and time slot reservation for SC and dynamically adjusting CW and CCI as nodes increase to reduces transmission delay than IEEE 1609.9, C-MAC(: Coordinated multi-channel MAC, and Q-VCI(: QoS Variable CCH Interval) protocols.

Protocol supporting Variable-length Message using Reservation Slots in WDM Local Network (WDM Local Network에서 예약슬롯을 이용한 가변길이 메시지 지원 프로토콜)

  • 진교홍
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.5 no.2
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    • pp.257-262
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    • 2001
  • A new WDM-based protocol for scheduling a variable-length message is proposed in this paper Two control channels, reservation slot and control slot, are used to coordinate transmission and diminish the collisions of packet to minimize the across delay. When an idle control slot is available, control packet is transmitted on that slot and message is transferred. And the node continues to transmit its control packet through the corresponding slot every cycle, until the message is completely transmitted. If any control slot is not available, the node schedules the transmission time of message in earliest available time using reservation slots. The proposed scheduling algorithm shows better performance and lower access delay.

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A Study on the Design of KVMF 2.0 Protocol for Ensuring Backward/Forward Compatibility between Different KVMF Message Standard Versions

  • Jeong-Min, Lee;Won-Gi, Lim;Won-Jun, Cho;Yong-Cheol, Kim;Jeung-Sub, Lee
    • Journal of the Korea Society of Computer and Information
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    • v.28 no.3
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    • pp.45-58
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    • 2023
  • KVMF(Korean Variable Message Format) 1.0 protocol is the Army's standard tactical datalink protocol that defines standard messages and communication methods to enable data communication between various weapon systems through bitwise variable message processing. The protocol has been applied to a variety of Army weapon systems over the past decade and has contributed to upgrade the Army's operational capabilities by enabling the implementation of Network Centric Warfare (NCW), the core of modern warfare. Since the KVMF 1.0 protocol was applied, new weapon systems with new technologies have been introduced over time, and new weapon systems have new messages based on the characteristics of the weapon system. As a result, compatibility problems arose due to different message versions with existing weapon systems, and it was expected that these problems would continue to emerge in the future, considering the need for continuous message revisions. Therefore, it became necessary to solve this problem, so this paper proposed a KVMF 2.0 protocol design that guarantees compatibility between forward and backward versions. In this paper, we implemented the design as SW, and confirmed that the design worked successfully by test between forward and backward versions on test environment. Therefore, when the KVMF 2.0 protocol design is applied to a weapon system, we can expect that the weapon system can be compatible with the forward and backward versions working with the existing weapon systems as well as with the future weapon systems.