• The Transactions of the Korea Information Processing Society
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• v.5 no.5
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• pp.1274-1284
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• 1998

Multicasting plays an important role in providing multimedia services like audio and video conferencing and has been actively studied for many years. The study of multicasting has been mainly focused on finding a low-cost tree on the assumption that every edge of the tree has enough link capacity to be allocated to the amound of bandwidth required by a service. In some cases, however, a multicasting tree whose some edges do not have enough bandwidth to be allocated may exist. A typical example of this case is to multicast among the group users located in the different sub-networks in the interconnected networks composed of the high bandwidth networks such as B-ISDN and the low bandwidth networks such as PSTN and PSDN. This paper proposes a novel multicasting protocol for providing multimedia services in a wide area network interconnected by multiple heterogeneous networks. First, the paper discusses the inherent limitation of present multicasting protocols for the case. Second, se introduce a new concept, multiple QoS's for a service, which extends the implicit assumption that only one QoS is assigned to a service in order to overcome this limitation. Third, our multicasting protocol is designed based on the current Internet protocol stacks. Last, we perform simulations for possible scenarios to provide multimedia services in the network and analyze their pros and cons.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.41 no.9
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• pp.73-80
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• 2004

In this paper, we present the cell resequencing buffer to solve the cell sequence integrity problem of the Cyclic banyan network that is a high-performance fault-tolerant cell switch. By offering multiple paths between input ports and output ports, using the deflection self-routing, the Cyclic banyan switch offer high reliability, and it also solves congestion problem for the internal links of the switch. By the way, these multiple paths can be different lengths for each other. Therefore, the cells departing from an identical source port and arriving at an identical destination port can reach to the output port as the order that is different from the order arriving at input port. The proposed cell resequencing buffer is a hardware sliding window mechanism. to solve such cell sequence integrity problem. To calculate the size of sliding window that cause the prime cost of the presented device, we analyzed the distribution of the cell delay through the simulation analyses under traffic load that have a nonuniform address distribution that express tile Property of traffic of the Internet. Through these analyses, we found out that we can make a cell resequencing buffer by which the cell sequence integrity is to be secured, by using a, few of ordinary memory and control logic. The cell resequencing buffer presented in this paper can be used for other multiple paths switching networks.