• Journal of Internet Computing and Services
• /
• v.9 no.4
• /
• pp.85-96
• /
• 2008

An authentication procedure on wired and wireless network will be done based on the registration and management process storing both the user's IP address and client device's MAC address information. However, existent MAC address registration/administration mechanisms were weak in MAC Spoofing attack as the attacker can change his/her own MAC address to client's MAC address. Therefore, an advanced mechanism should be proposed to protect the MAC address spoofing attack. But, existing techniques sequentially compare a sequence number on packet with previous one to distinguish the alteration and modification of MAC address. However, they are not sufficient to actively detect and protect the wireless MAC spoofing attack. In this paper, both AirSensor and AP are used in wireless network for collecting the MAC address on wireless packets. And then proposed module is used for detecting and protecting MAC spoofing attack in real time based on MAC Address Lookup table. The proposed mechanism provides enhanced detection/protection performance and it also provides a real time correspondence mechanism on wireless MAC spoofing attack with minimum delay.

• Proceedings of the Korea Inteligent Information System Society Conference
• /
• 1999.10a
• /
• pp.281-289
• /
• 1999

The objective of this paper is to propose a brand new interface mechanism to provide more intelligent decision making support for EC problems. Its main virtue is based on a numerical process mechanism by using an Extended AND-OR Graph (EAOG)-based logic algebra. Using this mechanism, decision makers engaged in electronic commerce (EC) can effectively deal with complicated decision making problems. In the field of traditional expert systems research, AND-OR Graph approach has been suggested as a useful tool for representing the logic flowchart of the forward and/or backward chaining inference methods. However, the AND-OR Graph approach cannot be effectively used in the EC problems in which real-time problem-solving property should be highly required. In this sense, we propose the EAOG inference mechanism for EC problem-solving in which heurisric knowledge necessary for intelligent EC problem-solving can be represented in a form of matrix. Finally, we have proved the validity of our approach with several propositions and an illustrative EC example

• ETRI Journal
• /
• v.30 no.3
• /
• pp.441-450
• /
• 2008

The scalable extension of H.264, known as scalable video coding (SVC) has been the main focus of the Joint Video Team's work and was finalized at the end of 2007. Synchronization between media is an important aspect in the design of a scalable video streaming system. This paper proposes an efficient media synchronization mechanism for SVC video transport over IP networks. To support synchronization between video and audio bitstreams transported over IP networks, a real-time transport protocol/RTP control protocol (RTP/RTCP) suite is usually employed. To provide an efficient mechanism for media synchronization between SVC video and audio, we suggest an efficient RTP packetization mode for inter-layer synchronization within SVC video and propose a computationally efficient RTCP packet processing method for inter-media synchronization. By adopting the computationally simple RTCP packet processing, we do not need to process every RTCP sender report packet for inter-media synchronization. We demonstrate the effectiveness of the proposed mechanism by comparing its performance with that of the conventional method.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.2 no.4
• /
• pp.593-601
• /
• 1998

This paper shows the GUI-sharing mechanism based on GDI hooking that can be useful for group users to ,share application programs dedicated to specific systems in distributed environments. In order to implement a networked-group working for real-time bases, an application-sharing mechanism should be necessary. This paper presents the implementation issues of application-sharing mechanism and provides a way of group working by implementation of GDI hooking module using GDI library in Windows 95 environment.

• Journal of Korean Institute of Industrial Engineers
• /
• v.25 no.2
• /
• pp.192-203
• /
• 1999

This paper deals with the order release problem for minimizing weighted earliness and tardiness as well as Work In Process (WIP) in dynamic job shop environments. A newly designed hierarchical order release mechanism is developed for efficient real-time control of the earliness/tardiness and WIP. The hierarchical order release mechanism consists of the order release plan and the order release control which is composed of two procedures. The experimental results show that the proposed order release mechanism is superior to other four order release mechanisms under overall simulation conditions of utilization rate, due-date allowances, and earliness/tardiness cost structures. In addition, the difference of total cost among the four dispatching rules is much more reduced in the proposed order release mechanism than in other release mechanisms.

• Proceedings of the Korea Contents Association Conference
• /
• 2007.11a
• /
• pp.60-64
• /
• 2007

Increasing using multimedia services as VoIP, Video conference, DMB, IPTV, etc, it is necessary to increase network traffics and develop the mechanism about a flow control for real time traffic transmission. In order to transfer realtime multimedia data, the transfer rate can be control on network state data measuring packet losses of a receiver and delay time of packets through getting periodical feedback RTP/RTCP packet. This paper describes using efficiant flow control on multicast that can reduce errors according to getting feedback tranfer delay and proposes the mechanism that can adapt dynamic change of network. In simulation, the transfer rate can efficiently be control on dynamic change of network and it makes the maximum of the use of a bandwidth and the minimum of packet losses.

• The Journal of Information Systems
• /
• v.26 no.4
• /
• pp.1-15
• /
• 2017

Purpose Through the provision of real time performance information about who is contributing and who is not in Electronic Brainstorming, prior studies evidenced a significant performance gain. However, it has been observed that the quantity-based performance feedback alone does not have enough restrictiveness to guide the performance behavior throughout the idea generation session. We included the notion of goal setting into the process performance feedback mechanism in an effort to regulate performance behavior and to better understand why individuals in Electronic Brainstorming are not obtaining enough stimulation benefits in the group interaction process. Design/methodology/approach We had developed real-time visual process performance feedback and modified to include goal setting. This mechanism visually displays individuals' performances two-dimensionally (quality for each idea vertically and quantity of ideas horizontally along with their goals). As individuals' contributions accumulate, the mechanism reveals performance histories by connecting the sequence of ideas in a time-series format, telling stories of individuals' performances. Then, we compared the performance outcome from this study with the outcomes from two prior studies (i.e., Jung et al., 2010 and Jung, 2014). Findings The results showed that the inclusion of goal setting into the process performance feedback solved the issue in the previous study. That was the lower than expected magnitude of performance enhancement of process performance feedback when compared to that of quantity-based feedback. It appears that goals as a motivational technique provide standards for systematic self-evaluation, serving as a cue to regulate performance behavior by strengthening the linkage between effort and performance. Thus, goals seem to set up a self-fulfilling prophecy, preconditioning better performance. However, the outcome still showed that its performance magnitude is unsatisfactory because the outcome of this study turned out to be close to the outcome of just quantity-based performance feedback in Jung et al.'s (2010) study.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.14 no.2
• /
• pp.473-494
• /
• 2020

To provide a guaranteed Quality of Service (QoS) to real-time traffic in High-Speed Downlink Packet Access (HSDPA) core network, we proposed an enhanced mechanism. For an enhanced QoS, a Class-Based Low Latency Fair Queueing (CBLLFQ) packet scheduling algorithm is introduced in this work. Packet classification, metering, queuing, and scheduling using differentiated services (DiffServ) environment was the points in focus. To classify different types of real-time voice and multimedia traffic, the QoS provisioning mechanisms use different DiffServ code points (DSCP).The proposed algorithm is based on traffic classes which efficiently require the guarantee of services and specified level of fairness. In CBLLFQ, a mapping criterion and an efficient queuing mechanism for voice, video and other traffic in separate queues are used. It is proved, that the algorithm enhances the throughput and fairness along with a reduction in the delay and packet loss factors for smooth and worst traffic conditions. The results calculated through simulation show that the proposed calculations meet the QoS prerequisites efficiently.

• Journal of Korea Multimedia Society
• /
• v.2 no.1
• /
• pp.59-68
• /
• 1999

Multimedia applications have an ability to transmit a lot of data in real time. In mobile circumstances the replay of continuous multimedia data in real time causes frequent replay breaks and poor service quality because of low transmission speed and new transmission path settings in hand-off. To avoid these unfavorable side effects, we need a new mechanism which can transmit data efficiently between base station and mobile hosts, to control the buffers of mobile hosts, and to switch to a new transmission path rapidly in hand-off. The study is to propose how to give good service to mobile hosts during hand-off and the mechanism which can increase the number of mobile hosts in the cell unit.

• Journal of Korea Multimedia Society
• /
• v.10 no.7
• /
• pp.882-892
• /
• 2007

In this paper, we propose a mechanism for both scheduling the hybrid-task set which consists of periodic and aperiodic tasks and recovering tasks with transient faults on the level of the operating system. Existing embedded operating systems would not provide the scheduling of both periodic and aperiodic tasks. Also because of not supporting the recovery of task failures, they can not prevent system failure from transient task faults. Proposed method, on the level of operating system, is able to not only meet the deadlines of all periodic tasks but also complete the execution of aperiodic tasks. In addition, it is able to prevent the system failure from transient task faults by recovering the task faults.