• The KIPS Transactions:PartB
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• v.9B no.3
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• pp.303-310
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• 2002

In this paper, we propose a proxy caching scheme that stores a portion of a continuous media object or an entire object on the Internet. The proxy stores the initial fraction of a continuous media object and determines the optimal size of the initial fraction of the continuous media object to be cached based on the object popularity. Under the proposed scheme, the initial latency of most clients and the data transferred from a remote server can be reduced and limited cache storage space can be utilized efficiently. Considering the characteristics of continuous media, we also propose the novel popularity for the continuous media objects based on the amount of the data of each object played by the clients. Finally, we have performed trace-driven simulations to evaluate our caching scheme and the popularity for the continuous media objects. Through these simulations, we have verified that our caching scheme, PPC outperforms other well-known caching schemes in terms of BHR, DSR and replacement and that popularity for the continuous media objects based on the amount of the playback data can enhance the performance of caching scheme.

• Journal of KIISE
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• v.42 no.12
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• pp.1486-1494
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• 2015

While Linux-based mobile devices such as smartphones are increasingly used, they often exhibit poor response time. One of the factors that influence the user-perceived interactivity is the high page fault rate of interactive tasks. Pages owned by interactive tasks can be removed from the main memory due to the memory contention between interactive and background tasks. Since this increases the page fault rate of the interactive tasks, their executions tend to suffer from increased delays. This paper proposes a framework-assisted selective page protection mechanism for improving interactivity of Linux-based mobile devices. The framework-assisted selective page protection enables the run-time system to identify interactive tasks at the framework level and to deliver their IDs to the kernel. As a result, the kernel can maintain the pages owned by the identified interactive tasks and avoid the occurrences of page faults. The experimental results demonstrate the selective page protection technique reduces response time up to 11% by reducing the page fault rate by 37%.

• Journal of Internet Computing and Services
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• v.5 no.1
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• pp.15-23
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• 2004

This paper presents distributive web-caching technique on the Head-End-Network (HNET) to solve excessive load of multimedia sever and inefficient use of network resources, The proposed web-caching is not concentration of load for a specific Head-End-Node(HEN), and it has advantage that there is no copy of a specific item on distributive HENs. This technique distributively stores on HENs partial streams of requested videos from clients connected to HENs and the order of store streams follows the order of request of identical video items from HENs. Thus, storing streams on each HEN that requests sevice are different. When a client requests the cached video on some HENs, the HEN that connects him receives streams in the order of store from HENs which stored them and it transmits them to him. These procedures are performed under the control of SA. This technique uses cache replacement algorithm that the combination of LFU, LRU and the last remove for the first stream of videos In order to reduce end-to-end delay.

• Journal of Internet Computing and Services
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• v.12 no.2
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• pp.37-46
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• 2011

The importance of data service with mobile is becoming more and more significant with the development of wireless network. However, due to the several type of mobile devices and contents, there is a problem that mobile contents should be edited according to the features of the mobile devices and the service providers. Fortunately, there is some solutions that convert mobile contents automatically according to mobile operator. Nevertheless, it has some issues that the response time of content service is delayed when converting mobile contents in real-time. In this paper, we propose an image cache replacement algorithm for minizing the volume of the real-time image transformation. Also, using both of the pre-conversion method and the real-time conversion method to improve storage space and response time.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.23 no.6
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• pp.119-124
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• 2023

This paper proposes a new reference model that can represent data access with temporal locality and popularity bias. Among existing reference models, the LRU-stack model can express temporal locality, which is a characteristic that the more recently referenced data has, the higher the probability of being referenced again. However, it cannot take into account differences in popularity of the data. Conversely, the independent reference model can reflect the different popularity of data, but has the limitation of not being able to model changes in data reference trends over time. The reference model presented in this paper overcomes the limitations of these two models and has the feature of reflecting both the popularity bias of data and their changes over time. This paper also examines the relationship between the cache replacement algorithm and the reference model, and shows the optimality of the proposed model.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.30 no.9B
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• pp.610-618
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• 2005

As developed Internet and Computer Capability, Many Users take the many information through the network. So requirement of User that use to network was rapidly increased and become various. But it spend much time to accept user requirement on current network, so studied such as Active network for solved it. This Active node on Active network have the capability that stored and processed execution code aside from capability of forwarding packet on current network. So required execution code for executed packet arrived in active node, if execution code should not be in active node, have to take by request previous Action node and Code Server to it. But if this execution code take from previous active node and Code Server, bring to time delay by transport execution code and increased traffic of network and execution time. So, As used execution code stored in cache on active node, it need to increase execution time and decreased number of request. So, our paper suggest ANC caching technique that able to decrease number of execution code request and time of execution code by efficiently store execution code to active node. ANC caching technique may decrease the network traffic and execution time of code, to decrease request of execution code from previous active node.

• Journal of Korea Multimedia Society
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• v.7 no.8
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• pp.1066-1077
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• 2004

Dramatic increase in the number of Internet users want highly qualified service of continuous media contents on the web. To solve these problems, we present two network caching schemes(PPC, PPCwP) which consider the characteristics of continuous media objects and user access pattern in this paper. While there are plenty of reasons to create rich media contents, delivering this high bandwidth contents over the internet presents problems such as server overload, network congestion and client-perceived latency. PPC scheme periodically calculates the popularity of objects based on the playback quantity and determines the optimal size of the initial fraction of a continuous media object to be cached in proportion to the calculated popularity. PPCwP scheme calculates the expected popularity using the series information and prefetches the expected initial fraction of newly created continuous media objects. Under the PPCwP scheme, the initial client-perceived latency and the data transferred from a remote server can be reduced and limited cache storage space can be utilized efficiently. Trace-driven simulation have been performed to evaluate the presented caching schemes using the log-files of iMBC. Through these simulations, PPC and PPCwP outperforms LRU and LFU in terms of BHR and DSR.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.31 no.7B
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• pp.608-618
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• 2006

The increasing popularity of multimedia streaming services introduces new challenges in content distribution. Especially, it is important to provide the QoS guarantees as they are increasingly expected to support the multimedia applications. The service providers can improve the performance of multimedia streaming by caching the initial segment (prefix) of the popular streams at proxies near the requesting clients. The proxy can initiate transmission to the client while requesting the remainder of the stream from the server. In this paper, in order to apply the prefix caching service based on IETF's RTSP environment to the wireless networks, we propose the effective RTSP handling scheme that can adapt to the radio situation in wireless network and reduce the cutting phenomenon. Also, we propose the traffic based caching algorithm (TSLRU) to improve the performance of caching proxy. TSLRU classifies the traffic into three types, and improve the performance of caching proxy by reflecting the several elements such as traffic types, recency, frequency, object size when performing the replacement decision. In simulation, TSLRU and RTSP handling scheme performs better than the existing schemes in terms of byte hit rate, hit rate, startup latency, and throughput.