• The Journal of Korean Institute of Communications and Information Sciences
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• v.11 no.4
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• pp.227-236
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• 1986

In this paper, an integrated voice/data packet network with window flow control is modeled by a colsed multichain queueing system, and its performance is analyzed by the mean value analysis method. Particularly, for the analysis of a packet network having various kinds of messages with different priority classes, we introduce an approach based on the mean value analysis and the concept of effective capacity. By the mathematical analysis and computer simulation, we obtain the following network statistics in the steady state: Mean buffer occupancy at each node, utilization of link throughput of a virtual channel, and mean delay time of each message. Our iterative analysis method can predict the link data status in most cases within about 10 percent of accurady, and the statistics of voice messages and external data within 5 percent as compared to simulation results.

• International Journal of Computer Science & Network Security
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• v.22 no.7
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• pp.13-20
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• 2022

Basically Mobile Ad Hoc Network (MANET) is an autonomous system with the collection of mobile nodes, these nodes are connected to each other by using wireless networks. A mobile ad hoc network poses this quality which makes topology in dynamic manner. As this type of network is Ad Hoc in nature hence it doesn't have fixed infrastructure. If a node wishes to transfer data from source node to a sink node in the network, the data must be passed through intermediate nodes to reach the destination node, hence in this process data packet loss occurs in various MANET protocols. This research study gives a comparison of various Mobile Ad Hoc Network routing protocols like proactive (DSDV) and reactive (AODV, DSR) by using random topology with more intermediate nodes using CBR traffic. Our simulation used 50, 100, and 150 nodes variations to examine the performance of the MANET routing protocols. We compared the performance of DSDV, AODV and DSR, MANET routing protocols with the result of existing protocol using NS-2 environment, on the basis of different performance parameters like Packet Delivery Ratio, average throughput and average end to end delay. Finally we found that our results are better in terms of throughput and packet delivery ratio along with low data loss.

• The Journal of the Korea institute of electronic communication sciences
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• v.16 no.6
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• pp.1161-1174
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• 2021

UDP is an unreliable data transmission protocol, in contrast to TCP, which implements reliable data delivery based on flow control and retransmission methods. However, the TCP operation algorithm for guaranteeing reliability is inefficient in improving transmission performance, and above all, there is no need to transmit data using the TCP method for fields that do not require perfect integrity. In this paper, we intend to discuss ways to improve the stability while maintaining the existing performance of UDP. To this end, a program applied with packet buffering and relaying techniques was developed, and the performance and stability of the experiment were verified.

• Proceedings of the IEEK Conference
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• 2000.11a
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• pp.213-216
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• 2000

In this paper, we propose a new scheme which improves the IP address lookup time. The new scheme is composed of two core technologies, named the prefix alignment and the prefix distance ordering. Now, as the Internet is being used commonly by improving the data transmission capacity, the need for enlarging the bandwidth of the Internet is on the rise. IP address lookup performance problem is an important obstacle in the router executing high speed packet forwarding. This results from the fact that the prefixes routing table is composed of and the traffic being processed in unit time are largely on the increase. The proposed lookup scheme is divided into two parts in technology, the one is the algorithm forming a routing database(routing table), the other is the lookup procedure in the actual packet processing.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.40 no.10
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• pp.79-88
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• 2003

We demonstrate a novel all-optical packet switching system that is suitable for optical ring networks. For the demonstration, video signals are encoded into optical packets which are composed of header and payload. The optical packets are all-optically processed at a switching node based on all-optical header processor, packet-level clock extraction, bit-level clock extraction, all-optical data format converter and so on.

• Journal of Communications and Networks
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• v.16 no.3
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• pp.322-334
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• 2014

Multimedia content is very sensitive to packet loss and therefore multimedia streams are typically protected against packet loss, either by supporting retransmission requests or by adding redundant forward error correction (FEC) data. However, the redundant FEC information introduces significant additional bandwidth requirements, as compared to the bitrate of the original video stream. Especially on wireless and mobile networks, bandwidth availability is limited and variable. In this article, an adaptive FEC (A-FEC) system is presented whereby the redundancy rate is dynamically adjusted to the packet loss, based on feedback messages from the client. We present a statistical model of our A-FEC system and validate the proposed system under different packet loss conditions and loss probabilities. The experimental results show that 57-95%bandwidth gain can be achieved compared with a static FEC approach.

• Proceedings of the KIEE Conference
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• 2001.07c
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• pp.1832-1834
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• 2001

A new method of all optical packet header recognition scheme using a photorefractive hologram filter is presented. Wavelength encoded packet that has the header of a specific wavelength is assumed and the photorefractive filter can detect the wavelength. Concatenated electronics drives the optical switch to route the $\lambda$-encoded optical packet. The delay time at the switched signals are measured and compared with the original data stream.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.23 no.5
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• pp.957-962
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• 2013

This paper proposes the new enhanced 2-D(2-Dimension) FEC scheme. It analyzes the probability of entire packet loss rate of the existing 2-D FEC by mathematical modeling, finds the problem of the existing 2-D FEC, and deduces the new enhanced 2-D FEC scheme that reduces the entire packet loss probability.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2013.05a
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• pp.491-493
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• 2013

In this paper, standardization subject of packet optical broadband is classified Ethernet/MPLS-TP based packet transport technology(IEEE 802, IETF), PON based optical access network technology(ITU-T), OTN based optical access network technology(ITU-T) and Ehternet based data center technoloty(IEEE 802) for establishing standardization strategy. therefor studing domestic standardization items and driving strategy for each technologies.

• Journal of Communications and Networks
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• v.5 no.3
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• pp.230-239
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• 2003

In this paper, we propose a framework to study how to route packets efficiently in multipath communication networks. Two traffic congestion control techniques, namely, flow assignment and packet scheduling, have been investigated. The flow assignment mechanism defines an optimal splitting of data traffic on multiple disjoint paths. The resequencing delay and the usage of the resequencing buffer can be reduced significantly by properly scheduling the sending order of all packets, say, according to their expected arrival times at the destination. To illustrate our model, and without loss of generality, Gaussian distributed end-to-end path delays are used. Our analytical results show that the techniques are very effective in reducing the average end-to-end path delay, the average packet resequencing delay, and the average resequencing buffer occupancy for various path configurations. These promising results can form a basis for designing future adaptive multipath protocols.