• Title/Summary/Keyword: 매체접속제어 프로토콜

Search Result 50, Processing Time 0.022 seconds

Shared-medium Access Control Protocol for the ATM Access Network - Part I : DMR-II Protocol Architecture - (ATM 액세스망을 위한 공유매체 접속 제어 프로토콜 - I부 : DMR-II 프로토콜 구조 -)

  • 황민태;김장경;이정태
    • Journal of the Korea Institute of Information and Communication Engineering
    • /
    • v.2 no.3
    • /
    • pp.379-388
    • /
    • 1998
  • In this paper we propose a DMR-II shared-medium access control protocol which was developed for the ATM access network users to support isochronous and non-isochronous traffics simultaneously under the bandwidth sharing environment, and describe its architecture and operation principles. The DMR-II protocol uses the slotted-ring topology, and gives the higher transmission priority to the isochronous traffic than the non-isochronous traffic. To support the isochronous traffic it uses the slot reservation mechanism, and maintains the delay variation of the isochronous traffic beyond the threshold value by using the blocking mechanism whenever the total user traffic overflows the network's bandwidth limitation. for the non-isochronous traffic the DMR-II protocol lets all the nodes to have fair transmission chances by using the reset mechanism based on the window counter scheme.

  • PDF

Collision Detection and Resolution Protocol for Intra-Vehicle Wireless Sensor Networks (차량 내 무선 센서 네트워크를 위한 충돌 검출 및 해결 프로토콜)

  • Choi, Hyun-Ho
    • The Journal of The Korea Institute of Intelligent Transport Systems
    • /
    • v.15 no.5
    • /
    • pp.116-124
    • /
    • 2016
  • This paper proposes a medium access control protocol for collision detection and resolution when a large number of sensor nodes transmits data in vehicle. The proposed protocol selects a random collision detection (CD) slot after data transmission, suspends its transmission and senses the channel to check whether a collision occurs by the detection of both energy level and jam signal. The proposed scheme uses multiple CD phases and in each CD phase, colliding stations are filtered and only surviving stations compete again in the next CD phase; thus, the collision resolution probability significantly increases. Simulation results show that the proposed protocol using the multiple CD phases has significantly better throughput than the conventional protocol. In addition, according to the number of CD phases and the number of CD slots per phase, the throughput aspect of the proposed scheme is investigated and the optimal parameters are derived.

Implementation of QoS-awared MAC Protocol for Home Networks (홈 네트워크를 위한 QOS 보장형 매체접속제어 프로토콜의 구현)

  • 황원주
    • Journal of the Korea Institute of Information and Communication Engineering
    • /
    • v.7 no.2
    • /
    • pp.228-238
    • /
    • 2003
  • We believe that existing wire solutions such as HomePNA2.0 using phone lines and HomePlug using power line and wireless solution such as HomeRF are the most promising solutions, because of its cost-effectiveness. However, MAC protocols of these solutions provide only Class of Service(CoS) using priority mechanism like HomePNA and HomePlug or consider only voice among real-time traffics like HomeRF. For these reasons, we perceive the needs of the new MAC protocol which is no new wire solution and provides guaranteed Quality of Service (QoS) for not only voice but also video and audio. In light of this, we present the design and software implementation of a new MAC protocol for Home Networks. Our evaluation results of software implementation verify that proposed MAC protocol can provide low delay, low loss, and low jitter to real-time traffic by reserving bandwidth.

A Token-Ring-Based MAC Protocol in IEEE 802.11 WLANs (IEEE 802.11 무선 랜에서의 토큰링 기반의 매체 접속 제어 프로토콜)

  • Lee, Eun Guk;Rhee, Seung Hyong
    • The Journal of Korean Institute of Communications and Information Sciences
    • /
    • v.39B no.1
    • /
    • pp.38-40
    • /
    • 2014
  • In this paper, proposed method achieves delay reduction and throughput improvement by utilizing token-ring method in infrastructure network. Access Point gives token passing effect by successively transmitting ACK frame including a node's Association ID. Not only can this method considerably reduce time for medium access, but also improve throughput. Furthermore, AP offers more frequent medium access opportunity to node having highest data queue among nodes associated by AP. these method can evenly offer medium access opportunity according to Queue's volumes.

A Study On The Wireless ATM MAC Protocol Using Mini-slot With Dynamic Bandwidth Allocation Algorithm (동적 대역 할당 알고리즘을 이용한 미니슬롯 기반의 무선 ATM 매체 접속 제어 프로토콜에 관한 연구)

  • Jeong, Geon-Jin;Lee, Seong-Chang
    • Journal of the Institute of Electronics Engineers of Korea TC
    • /
    • v.37 no.2
    • /
    • pp.17-23
    • /
    • 2000
  • Wireless link has high bit error rate compared with wired link and many users share this limited bandwidth. So it needs more powerful error control code and efficient media access control(MAC) to provide multimedia service reliably. In this paper we proposed efficient MAC frame format based on TDMA using mini-slot for request access. The number of mini-slots is variable based on the result of collision in the previous frame. This dynamic allocation of request mini-slots helps resolve the contention situation quickly and avoids the waste of bandwidth that may occur when there are several unneeded request mini-slots. The simulation results are also presented in terms of channel utilization, call blocking probability and cell transmission delay for mixed traffic environment.

  • PDF

A bidirectional full duplex medium access control protocol for underwater acoustic networks (수중 음향 네트워크를 위한 양방향 전이중 매체 접속 제어 프로토콜)

  • Kang, Sung Min;Hwang, Ho Young;Cho, Ho-Shin
    • The Journal of the Acoustical Society of Korea
    • /
    • v.36 no.3
    • /
    • pp.211-217
    • /
    • 2017
  • In this paper, we propose a bidirectional full duplex MAC (Medium Access Control) protocol for underwater acoustic networks. An underwater sensor node can set a back-off timer according to the priority of transmission. When the back-off timer expires, the underwater sensor node acquires a transmission opportunity. If a source node wants to send data to a destination node, it broadcasts RTS (Request-To-Send) including ID of the destination node to neighbor nodes. The destination node receiving RTS sends CTS (Clear-To-Send) to the source node to inform the bidirectional full duplex communication. After the source node receives CTS, the source node and the destination node can send the data to each other. In the underwater environment, the existing MAC protocol may take a lot of time for successful transmission of data due to long underwater propagation delay. On the other hand, the proposed bidirectional full duplex MAC protocol improves the throughput by shortening the time for successful transmission of data. In this paper, we analyze the throughput of the proposed bidirectional full duplex MAC protocol. In addition, we show that the proposed bidirectional full duplex MAC protocol has better performance in the presence of the long underwater propagation delay compared with existing MAC protocols for underwater environments.

Effect of Interference in CSMA/CA Based MAC Protocol for Underwater Network (CSMA/CA 기반 수중 통신망에서 간섭의 영향 연구)

  • Song, Min-je;Cho, Ho-shin;Jang, Youn-seon
    • The Journal of Korean Institute of Communications and Information Sciences
    • /
    • v.40 no.8
    • /
    • pp.1631-1636
    • /
    • 2015
  • With the advance of wireless communication technology in terrestrial area, underwater communication is also evolving very fast from a simple point-to-point transmission to an elaborate networked communications. Underwater acoustic channel has quite different features comparing with the terrestrial radio channel in terms of propagation delay, Doppler shift, multipath, and path loss. Thus, existing technologies developed for terrestrial communication might not work properly in underwater channel. Especially medium access control (MAC) protocols which highly depend on propagation phenomenon should be newly designed for underwater network. CSMA/CA has drawn lots of attention as a candidate of underwater MAC protocol, since it is able to resolve a packet collision and the hidden node problem. However, a received signal could be degraded by the interferences from the nodes locating outside the receiver's propagation radius. In this paper, we study the effects of interference on the CSMA/CA based underwater network. We derived the SNR with the interference using the sonar equation and analyzed the degradation of the RTS/CTS effects. These results are compared with the terrestrial results to understand the differences. Finally we summarized the design considerations in CSMA/CA based underwater network.

A study on the MAC protocol for an aeronautical mobile data communication (항공용 이동 무선 데이터 통신에 적합한 매체접속제어 프로토콜에 관한 연구)

  • 이은주;박효달
    • The Journal of Korean Institute of Communications and Information Sciences
    • /
    • v.22 no.11
    • /
    • pp.2604-2612
    • /
    • 1997
  • Media access control(MAC) protocol that is used between aircraft and ground station now is non-persistent CSMA protocol, but this protocol hs defects to apply in the wireless mobile radio communication environment. In this paper, to solve this Problems, the modified ICMA/CD protocol which ban be applied in the wireless environment was proposed and analyzed. In the modified ICMA/CD protocol, instead of usig special control channel, control signal was inserted into the uplink message. After the analysis, simulation was performed to approve the analysis resutls. As a results, modified ICMA/CD protocol can solve the hidden termined effect of CSMA protocol and packet detection delay time problem of ICMA/CD protocol and acquired the same channel throughput as CSMA/CD protocol. This results shows the modified ICMA/CD protocol can be used in the aeronauical telecommunication.

  • PDF

Performance Evaluation of the HIPERLAN Type 2 Media Access Control Protocol (HIPERLAN 타입 2 매체접근제어 프로토콜의 성능평가)

  • Cho, Kwang-Oh;Park, Chan;Lee, Jong-Kyu
    • The Journal of Korean Institute of Communications and Information Sciences
    • /
    • v.28 no.1B
    • /
    • pp.11-17
    • /
    • 2003
  • In this paper, we presented the dynamic random access channel allocation method under the priority based scheduling policy in order to improve the system performance of HIPERLAN/2 standardized by ETSI According to the scheduling policy, AP scheduler primarily allocates the resource to the collision MT This scheduling policy bring about decreasing the transmission delay of collision MT Dynamic RCH(random access channel) allocation method decreases the collision probability by increasing the number of RCH slots in case of low traffic. While it increases the maximum throughput by increasing the number of the data transmission slots in case of high traffic Therefore dynamic allocation method of RCH slots decreases the scheduling delay and increases the throughput When we evaluate the performance of presented method based on standards, we saw that the presented method improve the performance of the MAC protocol in terms of throughput and transmission delay.