• Journal of information and communication convergence engineering
• /
• 제8권1호
• /
• pp.71-76
• /
• 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.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• 제3권3호
• /
• pp.251-265
• /
• 2009

VoIP service is the transmission of voice data using SIP protocol on an IP-based network. The SIP protocol has many advantages, such as providing IP-based voice communication and multimedia service with low communication cost. Therefore, the SIP protocol disseminated quickly. However, SIP protocol exposes new forms of vulnerabilities to malicious attacks, such as message flooding attack. It also incurs threats from many existing vulnerabilities as occurs for IP-based protocol. In this paper, we propose a new virtual proxy to cooperate with the existing Proxy Server to provide state monitoring and detect SIP message flooding attack with IP/MAC authentication. Based on a proposed virtual proxy, the proposed system enhances SIP attack detection performance with minimal latency of SIP packet transmission.

• 전자공학회논문지B
• /
• 제33B권10호
• /
• pp.12-19
• /
• 1996

Many recent supercomputers employ a kind of switch-based multistage interconnection network architectrues (MINs) for constructing scalabel parallel compters. This paper proposed a new routing method, hybrid wormhole and virtual-cut through routing (HWCR) for the prevention of rapid performance degradation comming from a conflict in links usage at hot traffic situation. This HWCR through (VCT) for the fast removing temporal stagger, result in seamless flow of packet stream. When the blocked link is removed, wormhole routing is resumed. The HWCR method adopted a hierachical buffer scheme for improving the network performance and reducing the cost in BMINs. We could get optimum buffer size and communicatin latency through the computer simulation based on proposed HWCR, and the results were compared to those using wormhole and VCT.

• 한국컴퓨터정보학회:학술대회논문집
• /
• 한국컴퓨터정보학회 2016년도 제53차 동계학술대회논문집 24권1호
• /
• pp.103-104
• /
• 2016

사물 인터넷에서는 대부분의 기기가 와이맥스와 같은 무선 통신을 사용하는데 음영지역이 발생할 경우 펨토셀이 필요하다. 펨토셀은 안전적인 통신을 제공하지만 외부에서 무선 송신을 통해 접근할 수 있어 중간자 공격이 발생하기 쉽다. 강제 지연 인터락 프로토콜은 중간자 공격을 탐지하지만 고정된 지연 시간을 통해 패킷 전송 시간은 일정하다. 본 논문은 평가 함수를 사용하여 동적 지연 시간 결정을 통해 패킷 전달 시간에 대해 감소하는 방법을 제안한다. 이로 인해 제안 기법에서는 지연 시간이 효율적으로 감소하여 전송 속도를 향상한다.

• 한국멀티미디어학회논문지
• /
• 제7권6호
• /
• pp.814-823
• /
• 2004

Current video games and game room games are played as a single player mode on the basis of various emulators. With the evolution of data communications and game technology, a new trend in the game industry has made the primary interests of game developers and companies in the game industry be moved toward a multiplayer mode from the traditional single player mode. In this paper, we represent how to implement a network game platform by allowing network modules to be run in conjunction with the current video emulator games. It also suggests a synchronization scheme for real-time game playout and practical mechanism that can support network games to be played with the Peer-to-Peer process using a lobby system.

• ETRI Journal
• /
• 제29권6호
• /
• pp.745-754
• /
• 2007

In this paper, we present the Enhanced Communication Transport Protocol-Part 5 (ECTP-5), which provides scalable and reliable multicast communication service for many-to-many applications by constructing high quality recovery trees from two-layer logical trees and repairing the losses via unicast automatic repeat request-based error control. In order to realize the protocol, we developed feasible protocol architectures and building blocks including additional functions which deal with engineering details, such as membership dynamics and sender coordination. Experimental results show that ECTP-5 scales well with various session sizes and packet loss rates in terms of control overhead and recovery latency.

• ETRI Journal
• /
• 제45권6호
• /
• pp.1065-1078
• /
• 2023

In vehicular networks, diverse safety information can be shared among vehicles through internet connections. In vehicle-to-internet communications, vehicles on the road are wirelessly connected to different cloud networks, thereby accelerating safety information exchange. Onboard sensors acquire traffic-related information, and reliable intermediate nodes and network services, such as navigational facilities, allow to transmit safety information to distant target vehicles and stations. Using vehicle-to-network communications, we minimize delays and achieve high accuracy through consistent connectivity links. Our proposed approach uses intermediate nodes with two-hop separation to forward information. Target vehicle detection and routing of safety information are performed using machine learning algorithms. Compared with existing vehicle-to-internet solutions, our approach provides substantial improvements by reducing latency, packet drop, and overhead.

• 대한전자공학회:학술대회논문집
• /
• 대한전자공학회 2000년도 추계종합학술대회 논문집(3)
• /
• pp.165-168
• /
• 2000

Since the IP multicast was proposed, there have been many research works on reliable multicast protocols［1］. In multicast communication, many reliable multicast schemes were studied in order to overcome packet losses in the network. However the fact that packets are lost in the underlying networks but the solutions are sought in the end hosts makes the search for solutions difficult. If routers can identify packets before dropped from congestion, the routers can initiate recovery process. recovery scheme by routers is proposed. This scheme is much faster than by sender-initiated or receiver-initiated recovery and latency is smaller.

• 한국통신학회논문지
• /
• 제35권11C호
• /
• pp.877-884
• /
• 2010

본 논문에서는 차량 네트워크에서 다중 무선 네트워크 인터페이스를 이용한 고속 IP 이동성 관리 방법을 제시한다. 구체적으로, IETF HMIPv6의 MAP과 차량 네트워크의 이용 게이트웨이 간에 동적으로 다중 터널링을 생성하여 핸드오버 시 패킷 손실 및 지연시간을 최소화 하였다. 제안된 방법의 우수성을 증명하기 위해 수학적인 분석을 수행하였고, 기존의 이동성 관리 방법과의 성능 비교를 위해 NS-2 시뮬레이션을 수행하였다.

• 한국정보통신설비학회:학술대회논문집
• /
• 한국정보통신설비학회 2008년도 정보통신설비 학술대회
• /
• pp.486-490
• /
• 2008

본 논문에서는 Spurious NAK Suppression알고리즘을 통하여 RLP의 성능향상에 대한 기법을 제안한다. 일반적으로, Hybrid ARQ기법에서는 MAC과 Physical Layer에서의 Retransmission 및 Error Correction으로 무선환경에서의 Error를 줄이고 latency를 보장하고 있다. 그러나 Hybrid ARQ에서의 Multiple SAW나 Selective-ARQ에 의해서 인접한 Packet들 간의 out-of-sequence문제가 발생할 수 밖에 없으며, upper layer인 RLP(혹은 RLC)에서는 이를 re-sequencing하여야 하는 부담감이 생기게 된다. 본 논문에서는 RLP receiver에서의 re-sequencing방법에 있어서, 효율적으로 RLP-NAK의 전송시점을 결정하는 NAK suppression 방법을 제안하고 있으며, 실험을 통하여 높은 성능향상을 보임을 확인할 수 있다.