• International Journal of Computer Science & Network Security
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• v.21 no.12
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• pp.207-212
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• 2021

A buffer overflow attack is carried out to subvert privileged program functions to gain control of the program and thus control the host. Buffer overflow attacks should be prevented by risk managers by eradicating and detecting them before the software is utilized. While calculating the size, correct variables should be chosen by risk managers in situations where fixed-length buffers are being used to avoid placing excess data that leads to the creation of an overflow. Metamorphism can also be used as it is capable of protecting data by attaining a reasonable resistance level [1]. In addition, risk management teams should ensure they access the latest updates for their application server products that support the internet infrastructure and the recent bug reports [2]. Scanners that can detect buffer overflows' flaws in their custom web applications and server products should be used by risk management teams to scan their websites. This paper presents an experiment of buffer overflow vulnerability and attack. The aims to study of a buffer overflow mechanism, types, and countermeasures. In addition, to comprehend the current detection plus prevention approaches that can be executed to prevent future attacks or mitigate the impacts of similar attacks.

• Journal of KIISE:Databases
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• v.27 no.4
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• pp.549-561
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• 2000

In database management systems(DBMSs), partial rollback is a useful facility that cancels part of the executed operations upon user's requests without a total rollback. Many relational DBMSs(RDBMSs) provide this facility, However, object-orientccd DBMSs (OODBMSs) cannot utilize the previous recovery scl18lne of partial rollback usccd in (RDBMSs) since, unlike RDBMSs, they use a dual buffer consisting of an object buffer and a page buffer. Therefore, a new recovery scheme is required that rolls back the data efficiently in the dual buffer. We propose four partial rollback schemes in OODBMSs that use a dual buffer. We classify the proposed schemes into the single buffer based partial rollback scheme and the dual buffer based partial rollback scheme according to the number of buffers used for partial rollback processing. We further classify them into Uthe page buffer based partial rollback scheme, 2)the object buffccr based partial rollback scheme, 3)the dual buffer based partial rollback scheme using soft log, and 4)the dual buffer based partial rollback scheme using shadows. We evaluate the performance by mathematical analysis and experiments. The results show that the dual buffer based partial rollback scheme using shadows provides the best performance.

• Journal of the Institute of Convergence Signal Processing
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• v.5 no.1
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• pp.79-83
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• 2004

The purpose of ATM traffic management is to protect the network using minimum resources and guarantee the requred QoS and also it is desirable to provide fairness between input channels. In this paper, we propose the TBBM(threshold based buffer management) algorithm to improve fairness between input channels and utilization of ATM networks. TBBM algorithm controls output cell rate dynamically based on threshold. The result shows that the required bandwidth of the TBBM algorithm is 14.3% lower in audio traffic and 41.8% lower in video traffic than that of theoretically calculated equivalent capacity method. and also reveals that the TBBM algorithm provide improved CLR fairness between input channels

• The KIPS Transactions:PartD
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• v.11D no.1
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• pp.51-60
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• 2004

In open GIS environment, a GIS client can access spatial data in different types of GIS sowers with the same Interfaces. This means that open GIS components software ensures the interoperability throughout the heterogeneous GIS servers. The user response time, however, tends to be increased, if the client makes use of the standard interfaces for data accesses that can ensure interoperability. This is because the format of spatial data accessed from a specific GIS server must be transformed into common format, such as Rowset in OLE/DB, which is compatible with the standard interfaces. In this paper, we develop efficient techniques for data buffering in GIS client to reduce the response time. We design the buffer management method, which Is based on the space partitioning, and Integrate buffer management components into MapBase, an open GIS component software. And we also, show that buffer management proposed in this paper yields significant performance improvement in GIS client.

• Journal of the Institute of Convergence Signal Processing
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• v.7 no.3
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• pp.136-142
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• 2006

Existing buffer management schemes for shared-memory output queueing switches can be classified into two types: In the first type, some constant amount of memory space is guaranteed to each virtual queue using static queue thresholds. The static threshold method (ST) belongs to this type. On the other hand, the second type of approach tries to maximize the buffer utilization in 머 locating buffer memories. The complete sharing (CS) method is classified into this type. In the case of CS, it is very hard to protect regular traffic from mis-behaving traffic flows while in the case of ST the thresholds can not be adjusted according to varying traffic conditions. In this paper, we propose a new buffer management method called weighted dynamic thresholds (WDT) which can process packet flows based on loss priorities for quality-of-service (QoS) functionalities with fairly high memory utilization factors. We verified the performance of the proposed scheme through computer simulations.

• KIPS Transactions on Computer and Communication Systems
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• v.6 no.6
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• pp.255-260
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• 2017

The limitation of real-time video conferencing system is that the delay of network and buffering and the transmission of user information are not efficiently performed between systems, so real - time performance is not guaranteed completely. In order to overcome this problem, the study on the extension of the network infrastructure and the jitter delay is actively carried out, but the study on the buffering delay is insufficient. In this paper, we propose a frame-rate control buffer management (FRCB) scheme to solve the problem caused by buffering delay. The FRCB is used to prevent overflow and underflow of the buffer by adopting the two-stage buffer threshold of Fast-play THreshold (FTH) and Slow-play THreshold (STH). Therefore, it showed better performance than jitter buffer even under high CPU load, and showed that it is suitable for high quality real time video conferencing.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.40 no.6
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• pp.1208-1216
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• 2015

In this paper, we use WiMedia WLP-based networks to meet the demand for IT services of a ship. If a mobile node moves to a congested base station of a new subnetwork, we will propose a scheme for improving performance of radio link of existing communicating mobile nodes. An old base station denotes packets stored during a handover. And, a proposed buffer management determines to discard the buffered packets in accordance with congestion degree at the congested new base station. Simulation results show that the proposed buffer management scheme improves link utilization in congested wireless links.

• Journal of Korea Multimedia Society
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• v.6 no.5
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• pp.842-848
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• 2003

The Guaranteed Frame Rate(GFR) service has been designed to accomodate non-real-time applications, such as TCP/IP based traffic in ATM networks. One of the important factors is buffer management for guaranteeing QoS in GFR service. In this paper, we propose a buffer management scheme which can improve the fairness and the throughput through the traffic control in GFR service. For the evaluation of the proposed scheme, we compare proposed scheme with the existing scheme in the fairness and the throughput. Simulation results show that proposed scheme can improve the fairness and throughput than the existing scheme.

• KIPS Transactions on Computer and Communication Systems
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• v.5 no.7
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• pp.153-158
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• 2016

Delay Tolerant Network (DTN) is a network that employed method of store-carry-forward in intermittently connected networks. In DTNs, routing and buffer management scheme are important to improve successful message delivery. This paper proposes an improve spray and wait routing protocol based on delivery probability to a destination. Also, a buffer management scheme is proposed to drop the queued messages according to the number of copies (L value). Simulation results show that the proposed method provides a better delivery ratio and lower communication overhead when compared to existing schemes such as Epidemic, PRoPHET and spray and wait.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.9 no.1
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• pp.128-133
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• 2005

Respond time and processing rate representing how many tasks can be done during an unit time in a client/server environment are generally use for measuring the performance of computers. In this paper, we suggest a window buffer managing scheme based on a window with many of short-term sliced slots where a media stream is allocated and deallocated into them so that it can maximize the utilization ration of the limited buffer on a multimedia server. And we also propose a buffer substitution scheme for reducing I/O times of a multimedia server by counting re-reference time point about a used block and then it can be reused by the next consecutive media stream.