• Journal of Korea Multimedia Society
• /
• v.6 no.7
• /
• pp.1231-1238
• /
• 2003

As the demand on multicast services increases to support the terminal mobility in the midst of the development of wireless mobile communication technology, many new methods have been studied. However, previous methods occur delay and packet loss during re-joining to multicast service group when moving mobile node. In this paper, we will propose a scheme that decreases packet loss using regional registration method. Proposed scheme modified signaling message of previous regional-registration and added caching. In case move to same GFA, we can prevent packet loss by keeping registration to FA until perfectly registration ends. Also, In case move to other GFA, we can reduce packet loss by using cache. Therefore, we can receive efficient multicast service.

• Proceedings of the Korea Contents Association Conference
• /
• 2007.11a
• /
• pp.270-273
• /
• 2007

The overlay multicast that has been recently presented as an alternative for the IP multicast has been getting much persuasion by the advancement of the network techniques to enforce routing in application-level. But, The overlay multicast is a problem of delay and the load of the traffic control. In this paper, we suggested to an effective transmission routing tree between users based on overlay multicast of Internet broadcasting Service. And we evaluated an optimal value of transmission delay about Internet broadcasting using this suggest model.

• Journal of the Korea Society of Computer and Information
• /
• v.13 no.6
• /
• pp.233-241
• /
• 2008

The overlay multicast that has been recently presented as an alternative for the IP multicast needs scheduling method that can apply the system resource and the network bandwidth for the many users. We propose a efficient overlay multicasting network policy for multimedia services with composite stream service topology. And in order to evaluate the ability of the proposed scheme's performance, We test the performance of multi_casting nodes with RTT values, the bandwidth attrition rate for building the network topology and MOR effects with Overcast[5] The result of simulation shows improves about $8{\sim}20%$ of performance.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.36 no.4B
• /
• pp.305-313
• /
• 2011

This paper presents a P2P (Peer-to-Peer) overlay multicast tree construction algorithm to support stable multimedia service over the Internet. While constructing a multicast tree, it takes into account not only the link delay, but also peer stability. Since peers actually show dynamic and unstable behavior over P2P-based network, it is essential to consider peer stability. Furthermore, the weighting factor between link delay and peer stability is adaptively controlled according to the characteristics of the multicast tree. Basically, Genetic algorithm is employed to obtain a near optimal solution with low computational complexity. Finally, simulation results are provided to show the performance of the proposed algorithm.

• Journal of KIISE:Information Networking
• /
• v.33 no.1
• /
• pp.9-15
• /
• 2006

While a lot of important information is being sent and received on the Internet, the information could be exposed to many threats, and the more the Multicast Service is various and generalized, the more the service range is widened. When a new member joins in or leaves from the Multicast Group, the Group Key, which the existing member use for, should be newly updated. The existing method had a problem that the performance was depreciated by the key exchanging. This paper proposes the effective group management mechanism for a secure transmission of the Multicast Data on the Multicast Group.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.5 no.4
• /
• pp.741-762
• /
• 2011

Recently, multicast routing protocols become increasingly important aspect in Mobile Ad hoc Networks (MANETs), as they effectively manage group communications. Meanwhile, multimedia and real-time applications are becoming essential need for users of MANET. Thus it is necessary to design efficient and effective Quality of Service (QoS) multicast routing strategies. In this paper, we address the scalability problem of multicast routing protocols to support QoS over MANETs. In particular, we introduce a Position-Based QoS Multicast Routing Protocol (PBQMRP). Basically, the protocol based on dividing the network area into virtual hexagonal cells. Then, the location information is exploited to perform efficient and scalable route discovery. In comparison with other existing QoS multicast routing protocols, PBQMRP incurs less control packets by eliminating network flooding behavior. Through simulation, the efficiency and scalability of PBQMRP are evaluated and compared with the well-known On-Demand Multicast Routing Protocol (ODMRP). Simulation results justify that our protocol has better performance, less control overhead and higher scalability.

• Journal of Korea Society of Industrial Information Systems
• /
• v.14 no.4
• /
• pp.49-56
• /
• 2009

Recently, studies for effective multimedia contents delivery have been widely performed in the multimedia streaming area. Overlay multicast, which can be implemented in the application layer, is method to transmit multimedia content's effectively. The Overlay multicast method can implement multicast transmission without changing the physical layer, and it has the characteristic that the application method can be diversify according to the algorithm. This paper has proposed the backup path construction method of overlay multicast for stabilized multimedia contents transmission. The proposed method can construct a backup path with the minimum searching method for guaranteed QoS(Quality of Service) and in overlay multicast so a fast and simple backup path can be constructed.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.20 no.12
• /
• pp.2267-2273
• /
• 2016

In this paper, WiMedia Distributed-MAC protocol is adopted for development of an OSMU (One Source Multi Use) N-screen wireless multicast service. But, when considering wireless communication environment where channel error rate is time-variant, N-screen high-speed data is vulnerable to be lost. For this problem, a multicast relay scheme is proposed by analyzing Distributed-MAC protocol. In proposed multicast relay scheme, Multicast-free DRP Availability IE is combined and the relay node suitable for N-screen multicast transmissions is selected. Through this operation, it can avoid wireless channel with high errors and can transmit N-screen high-speed data. In simulation results, the proposed multicast relay scheme is compared with conventional Distributed-MAC multicast scheme in view points of throughput and energy consumption according to various numbers of multicast nodes and BER (Bit Error Rate) values in wireless channel. Through simulation results, it is explained that proposed multicast relay scheme should be adopted in WiMedia Distributed-MAC protocol to realize OSMU N-screen wireless multicast services.

• Journal of Korea Multimedia Society
• /
• v.3 no.3
• /
• pp.280-289
• /
• 2000

This paper presents an efficient method to provide seamless communication in mobile wireless networks. The goal of seamless communication is to provide disruption free service to a mobile user. A disruption in service could occur due to active handoffs. There are many user applications that do not require a total guarantee for disruption free service but would also not tolerate very frequent disruptions. This paper proposes an extended staggered multicast that provides a probabilistic guarantee for disruption free service. The proposed multicast forecasts the direction and velocity for a mobile host. It is possible that data packets for a mobile host are multicasted to not all neighbor cells but a par\ulcorner of neighbor cells those the mobile host will be handoff potentially on the basis of these information. Therefore, the extended staggered multicast significantly reduces the static network bandwidth usage also provides a probabilistic guarantee for disruption free service.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.35 no.7B
• /
• pp.1018-1033
• /
• 2010

Recently, as the use of mobile terminal is generalized, the needs of high-speed Internet mobile service is increased. Also users want to receive the multimedia contents what they want through the various terminals in anywhere, anytime via wired and wireless integrated environment. Therefore, various mechanisms that support the mobility are proposed. However, these mechanisms are difficult to support seamless mobility and QoS awareness on the mobile multicast environment. In this paper, we propose a QoS aware handover mechanism that is able to provide the high-quality and real-time services such as mobile IPTV in an integrated environment for these requests of users. Proposed mechanism manages the multicast admission control and multicast handover using the 2-layer multicast information management at the wired and wireless integrated network that extended the service guaranteed methods through the probing based admission control of the wired network to the wireless network based on PMIPv6. We present a performance evaluation results and features analyzed by the simulations using the ㎱-2.