• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2000년도 하계종합학술대회 논문집(3)
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• pp.145-148
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• 2000

ATM network is considered as best suitable technology for multimedia service in various aspects such as bandwidth, capability of traffic expandability and so on. In this paper, we suggested a buffer management algorithm in ATM network to improve overall network performance with threshold and auxiliary buffer whose input consists of superpositiI on of voice and multimedia data traffic. To evaluate the proposed buffer management algorithm simulations are executed with four priorities, that is delay and loss priorities and the results are proved that network throughput is improved better than the existing partial buffer method.

• International Journal of Internet, Broadcasting and Communication
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• 제12권4호
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• pp.166-172
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• 2020

Video streaming application such as YouTube is one of the most popular mobile applications. To adjust the quality of video for available network bandwidth, a streaming server provides multiple representations of video of which bit rate has different bandwidth requirements. A streaming client utilizes an adaptive bit rate scheme to select a proper video representation that the network can support. The download behavior of video streaming client player is governed by several parameters such as maximum buffer size. Especially, the size of the maximum playback buffer in the client player can greatly affect the user experience. To tackle this problem, in this paper, we propose the maximum buffer size optimization according to available network bandwidth and buffer status. Our simulation study shows that our proposed buffer size optimization scheme successfully mitigates playback stalls while preserving the similar quality of streaming video compared to existing ABR schemes.

• Journal of Communications and Networks
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• 제16권6호
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• pp.656-666
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• 2014

In delay tolerant networks (DTNs), delay is inevitable; thus, making better use of buffer space to maximize the packet delivery rate is more important than delay reduction. In DTNs, epidemic routing is a well-known routing protocol. However, epidemic routing is very sensitive to buffer size. Once the buffer size in nodes is insufficient, the performance of epidemic routing will be drastically reduced. In this paper, we propose a buffer scheme to optimize the performance of epidemic routing on the basis of the Lagrangian and dual problem models. By using the proposed optimal buffer scheme, the packet delivery rate in epidemic routing is considerably improved. Our simulation results show that epidemic routing with the proposed optimal buffer scheme outperforms the original epidemic routing in terms of packet delivery rate and average end-to-end delay. It is worth noting that the improved epidemic routing needs much less buffer size compared to that of the original epidemic routing for ensuring the same packet delivery rate. In particular, even though the buffer size is very small (e.g., 50), the packet delivery rate in epidemic routing with the proposed optimal buffer scheme is still 95.8%, which can satisfy general communication demand.

• 전기전자학회논문지
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• 제7권2호
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• pp.260-264
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• 2003

네트워크의 성능 향상에 영향을 미치는 여러 요소 중에서, 본 연구에서는 NIC(Network Interface Card) 버퍼 사이즈(Buffer Size)가 웹 서버와 LAN(Local Area Netwok)에 어떤 영향을 미치는지를 분석하였다. 버퍼 사이즈의 조절을 통해서 내부 네트워크의 패킷 분실율, 처리량, RTT(Round Trip Time), 수신율의 변화를 NS-2를 사용하여 시뮬레이션 해보고 그 결과를 비교하여 이더넷(Ethernet)에서의 웹 트래픽에 미치는 영향을 분석하였다.

• 한국정보과학회논문지:시스템및이론
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• 제33권11호
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• pp.810-819
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• 2006

본 논문에서는 네트워크 통신에서 혼잡으로 인한 패킷의 손실을 최소화하기 위하여 새로운 버퍼 모델인 적응적인 이중 버퍼 모델을 제안한다. 이는 제약된 메모리 환경에서 송수신 버퍼가 서로의 여유 공간을 공유하여 패킷의 손실을 최대한 줄일 수 있는 버퍼 모델이다. 또한 리스트와 비슷한 성능을 지니는 본 버퍼 모델은 자유 리스트를 사용한 버퍼와 달리 메모리 누수로 인한 버블(bubbles) 현상을 방지하므로 제한된 환경의 네트워크 버퍼에 적용할 수 있으며 배열을 사용하는 경우와 비교 할 때 최대 100% 성능 향상을 기대할 수 있다.

• International Journal of Computer Science & Network Security
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• 제23권1호
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• pp.153-163
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• 2023

This study is situated in the context of intelligent transport systems, where in-vehicle devices assist drivers to avoid accidents and therefore improve road safety. The vehicles present in a given area form an ad' hoc network of vehicles called vehicular ad' hoc network. In this type of network, the nodes are mobile vehicles and the messages exchanged are messages to warn about obstacles that may hinder the correct driving. Node mobilities make it impossible for inter-node communication to be end-to-end. Recognizing this characteristic has led to delay-tolerant vehicular networks. Embedded devices have small buffers (memory) to hold messages that a node needs to transmit when no other node is within its visibility range for transmission. The performance of a vehicular delay-tolerant network is closely tied to the successful management of the nodes' transit buffer. In this paper, we propose a message transit buffer management model for nodes in vehicular delay tolerant networks. This model consists in setting up, on the one hand, a policy of dropping messages from the buffer when the buffer is full and must receive a new message. This drop policy is based on the concept of intermediate node to destination, queues and priority class of service. It is also based on the properties of the message (size, weight, number of hops, number of replications, remaining time-to-live, etc.). On the other hand, the model defines the policy for selecting the message to be transmitted. The proposed model was evaluated with the ONE opportunistic network simulator based on a 4000m x 4000m area of downtown Bouaké in Côte d'Ivoire. The map data were imported using the Open Street Map tool. The results obtained show that our model improves the delivery ratio of security alert messages, reduces their delivery delay and network overload compared to the existing model. This improvement in communication within a network of vehicles can contribute to the improvement of road safety.

• 한국통신학회논문지
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• 제22권4호
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• pp.782-792
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• 1997

ATM은 광대역망에서 여러 형태의 멀티미디어 서비스를 지원하는 수단을 제공한다. 멀티미디어 서비스를 지원하기 위해서는 다수의 우선순위를 갖는 다양한 트래픽을 효율적으로 제어할 수 있어야 하며, 이러한 제어동작을 수행하기 위해서는 망내에 혼잡제어 기능이 요구된다. 이러한 문제를 유연하고 효과적으로 해결하기 위해서는 일반적으로 다단계의 서비스 레벨을 제공하는 방식이 사용된다. 본 논문에서는, ATM망에서 다른 우선순위를 갖는 음성과 데이타 트래픽이 다중화 되어 입력될 경우, 전체적인 망의 성능을 향상시키기 위해 임계치를 가지는 기존의 버퍼와 낮은 우선순위 셀을 수용하는 보조버퍼로 분할하는 방식을 사용하는 버퍼 관리 알고리즘을 제시하였다. 버퍼 관리 방법의 성능을 평가하기 위해 망내에 두가지의 우선순위를 고려하여 모의 실험을 수행하였고, 그 결과 기존의 분할 버퍼를 사용한 방법보다 전체적인 망의 성능이 향상되었음을 확인하였다.

• 전자공학회논문지A
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• 제33A권2호
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• pp.1-7
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• 1996

In this paper, we analyzed the packet blocking probability of a finite buffer in a network interface unit. In general, a network interface unit which provides a means of interface between the network and computer has a microprocessor and a protocol processor for the network access protocols. It also has a receive buffer for the arriving packets from the network which is served by the microprocessor with service interruption by the protocol processor. In this paper, we modeled the receive buffer as a discrete time server with service interruption, and obtained the packet blocking probability using the mini-slot approximation.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2000년도 추계학술대회 논문집 학회본부 D
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• pp.815-817
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• 2000

근래 Web Server의 안정된 운용의 중요성이 급증하는 Network Traffic과 더불어 점차 증대되고 있다. 기본적인 Network 구성망은 Ethernet으로 표준적인 프로토콜은 TCP/IP로 기반을 잡고 있다. 날로 증가하는 Network Traffic을 효과적으로 처리하기 위해서는 Network의 bandwidth 및 서버가 처리할 수 있는 데이터 양을 분석하여 병목현상을 줄이고 데이터의 흐름을 원활히 하기 위한 데이터 buffer들의 설치와 적절한 운영 방법에 관한 연구가 필요하다. 본 논문에서는 Web Server로부터 image 데이터를 전송 받아 이를 원활히 display하기 위한 Application Layer에서의 buffer 크기 및 제어방법에 관한 연구를 수행하고 특히 연속적인 이미지의 전송과 재생에 관한 buffer management에 관하여 고찰한다.

• International Journal of Control, Automation, and Systems
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• 제6권2호
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• pp.214-222
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• 2008

Bode principle is applied to carry out traffic control for rate based ATM network, which guarantees the higher buffer utilization, buffer overflow-free, and well utilization of bandwidth. The principle confirms the relationship between the threshold of buffer queue and the network bandwidth, as well as the relationship between the threshold of buffer and source input rate. Theoretic warrant of the buffer threshold is proposed. The reference range of source input rate is provided in theory, which makes the source end respond to the change of network state rapidly and dynamically, and then the effect of time delay to the traffic control is avoided. Simulation results show that the better steady and dynamic performances of networks are obtained by Bode principle.