• Journal of KIISE:Information Networking
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• v.33 no.6
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• pp.461-472
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• 2006

In this paper, we propose a novel on-demand multicasting algorithm, 'Durable Distance Vector Multicasting(DDVM),' for Mobile Ad hoc Network(MANET). DDVM has a more efficient routing-control complexity than Link State Routing(LSR) and with the smaller complexity, DDVM provides a high delivery ratio for MANET with high mobility by adapting to dynamic topological changes. This is achieved by adding 'combined path durability' statistic into the routing-control information of Distance Vector Routing(DVR). The routing-path duration statistic is computed in a fully distributed manlier at each node in the network based on only local information from neighbour nodes. We show by simulation studies the effectiveness of DDVM compared with On-demand Multicast Routing Protocol(ODMRP).

• Journal of Internet Computing and Services
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• v.3 no.4
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• pp.11-18
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• 2002

The IP multicasting service system based on IGMP(Internet Group Management Protocol) is the receiver initiated multicasting system that all receivers must join to and leave from the server of multicasting service. The IGMP is less effective and reliable to apply the education system that all computers of students ore synchronized a teacher's computer. A proposed middle-ware in this paper provides the reliable data transferring and the server initiated multicasting system that client as student's PC is controled by a multicasting server as teacher's PC, This middle-ware is consisted with two major component, The one is the group manager that handle the status informations of members in each group. Another is the reliable sender/receiver that has The transmission protocol based on NAK message and flow control. As the results of the test that 22khz digital voice data and 1024$\times$768 24bit color image data were tested for 30 PCs connected with 100baseT, the voice data was completely without error transferred and the image data was successfully transferred with 0.004% retransmit rate under 2 frames/sec load.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.30 no.11B
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• pp.772-783
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• 2005

In this paper, we propose an effective multicasting protocol in wireless ad-hoc networks. Conventional wired and wireless network multicast protocols do not perform well in wireless ad hoc networks because they were designed without consideration of ad hoc environments such as node mobility, limited bandwidth, high error probability. To solve this problem, some multicasting protocols for ad hoc network have been proposed in the literature. However, these protocols can not provide high packet delivery ratio, low control packet overhead and low expended bandwidth at the same time. Therefore, in this paper, we propose RTMA that improves multicasting performance in wireless ad hoc networks. RTMA calculates its current region from its position information by using GPS in order to make tree among the multicast group nodes in the same region. The proposed region-based tree method is for high packet delivery ratio, low control packet overhead when many senders send data packets. RTMA makes a reliable tree by using speed information to fill a gap of the weak points of the tree structure. When searching the routing path, RTMA selects the reliable path excluding high speed nodes.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.12 no.6
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• pp.229-240
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• 2012

The development of multimedia applications followed by development of high-speed networks has improved the performance of mobile devices with high transfer speed broadband. Mobile internet access has made possible seamless indoor and outdoor mobile multicast services. Multicasting services are used to support efficient group communications. However, mobile multicasting services have two constraints: tunnel convergence and handover latency. Many protocols and handover methods have been proposed to address these problems. The inter-LMA optimized handover model for multicasting services has previously been proposed for PMIPv6-based networks. The proposed model removes the tunnel convergence issue and reduces router processing costs. It also makes possible the performance of fast handover operations with adaptive transmission mechanisms. In addition, the proposed scheme exhibits low packet delivery costs and handover latency in comparison with existing schemes, and ensures fast handover when moving the inter-LMA domain

• The Journal of Korean Institute of Communications and Information Sciences
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• v.26 no.5A
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• pp.738-744
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• 2001

멀티캐스팅이란 일대일의 전형적인 통신 모델과 one-to-all 방식의 브로드캐스팅의 중간적인 일대다 통신 모델이다. 여러 가지 통신 어플리케이션에서 멀티캐스팅 서비스를 제공하기 위해서는 많은 요구사항이 필요하며, 이를 위하여 여러 가지 멀티캐스팅 프로토콜이 연구되어 왔다. 그 중 신뢰도를 보장하기 위하여 논리적인 트리를 구성하고, 이러한 계층적 트리 기반의 복구 메커니즘을 이용하여 오류를 복구, 흐름 및 혼잡을 제어하는 방식이 Tree-based Multicasting Protocol이다. 본 논문에서는 Tree-based Multicasting Protocol에서 기본이 되는 논리적 트리를 구성하는데 있어 Top-down 방식을 따르는 프로토콜과 Bottom-up 방식을 따르는 프로토콜의 트리 구성 방식을 살펴보고, 시뮬레이션을 통하여 멀티캐스팅 그룹에 참여하는 노드수가 증가함에 따라 트리 구성시 교환되는 메시지 수와 트리 구성 지연 시간, 트리 Depth 등을 비교하였다.

• 한국정보통신설비학회:학술대회논문집
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• 2007.08a
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• pp.89-91
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• 2007

Multimedia service based on interactivity, personalization, multiple channels and community distinguishes IPTV from incumbent TV. But data encoding/decoding time and image frame processing should be considered in digital TV versus analog device. Especially channel zapping time is one of the most important parameters for the service quality of IPTV. This paper proposes the mechanism for decreasing the channel zapping time with multiple decoder and image frame processing. We also implemented the multi-group video community service system using IP multicasting function supporting interactive learning service.

• Journal of information and communication convergence engineering
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• v.8 no.1
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• pp.71-76
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• 2010

Scalable video coding (SVC) has been standardized as an extension of the H.264/AVC standard. SVC allows straightforward adaptation of video streams by providing layered bit streams. In this paper, we propose a SVC video-based multicasting system preserving scalable security which is able to provide a SVC video service while maintaining information security. In order to maintain information security between a server and a client during all transmission time, the proposed system immediately performs a packet filtering process without decoding with respect to encrypted data received in a routing device, thereby reducing an amount of calculations and latency.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.22 no.12
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• pp.2626-2634
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• 1997

The purpose of multicasting is to reduce the network costs for transmitting the same traffic to multiple destinations. In this paper, an efficient delay-bounded multicasting routing algorithm is proposed, which satistifies the network conditions of cost minimization and can adjust the dynamic events, such as 'leave and/or join ones' from the multicast group. Also, our algorithm is designed for various network requirements such as the efficiet dynamic group support, high-quality data distribution, and adaptability to variable situation. After the delay tolerance and the maximum group size are determined according to network state and requirements for delay and cost, the dynamic delay-bounded multicast tree is constructed using partial multicast routing. We evaluate the performance of the proposed algorithm by running simulations on randomly generated test networks using a Sun Sparc 20 workstation. We were able to obtain good simulation resutls, which means solutions that lies between the minimum cost solution and the minimum delay one.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.28 no.12A
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• pp.991-1001
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• 2003

CCFH(Candidatecasting Fast Handoff) algorithm excels the performance of existing fast handoff schemes using multicasting in terms of handoff latency and B/W efficiency. The scheme uses L2 information(BSSID) at Wireless LAN and starts multicasting before L2 handoff. So it can reduce L3 handoff latency. At this article, we would show that Candidatecasting Fast Handoff Scheme is clearly new scheme using L2 information and has the good performance.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.8 no.1
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• pp.183-195
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• 2014

Multicasting is an efficient way of group communications because one sender can transmit data to multiple receivers with only one transmission. Furthermore, multicasting is considered an appropriate transmission method for multimedia services. Multimedia applications are expected to become more prevalent over mobile ad-hoc networks in the near future. Therefore, achieving reliability in multimedia communications is an important task. In this paper, we propose a leader-based reliable multicast medium access control layer protocol for multimedia applications to enhance video quality. We present a Markov chain model and numerical formulation of our proposed system.