• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.12 no.12
• /
• pp.6123-6138
• /
• 2018

Named data networking (NDN) is a new network architecture designed for next generation Internet. Router-side content caching is one of the key features in NDN, which can reduce redundant transmission, accelerate content distribution and alleviate congestion. However, several security problems are introduced as well. One important security risk is cache privacy leakage. By measuring the content retrieve time, adversary can infer its neighbor users' hobby for privacy content. Focusing on this problem, we propose a cache privacy protection mechanism (named as CPPM-DAM) to identify legitimate user and adversary using Bloom filter. An optimization for storage cost is further provided to make this mechanism more practical. The simulation results of ndnSIM show that CPPM-DAM can effectively protect cache privacy.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.16 no.5
• /
• pp.1653-1670
• /
• 2022

The fear that location privacy may be compromised greatly hinders the development of location-based service. Accordingly, some schemes based on the distributed architecture in peer-to-peer network for location privacy protection are proposed. Most of them assume that mobile terminals are mutually trusted, but this does not conform to realistic scenes, and they cannot make requirements for the level of location privacy protection. Therefore, this paper proposes a scheme for location attribute-based security authentication and private sharing data group, so that they trust each other in peer-to-peer network and the trusted but curious mobile terminal cannot access the initiator's query request. A new identifier is designed to allow mobile terminals to customize the protection strength. In addition, the caching mechanism is introduced considering the cache capacity, and a cache replacement policy based on deep reinforcement learning is proposed to reduce communications with location-based service server for achieving location privacy protection. Experiments show the effectiveness and efficiency of the proposed scheme.

• Journal of the Korea Institute of Information Security & Cryptology
• /
• v.30 no.4
• /
• pp.559-572
• /
• 2020

As internet technology advances, users can share content online, and many sharing services exist. According to a recently published digital forensic study, when playing an online streaming service, you can restore the played video by reconstructing the Chrome cache file left on local device such as a PC. This can be seen as evidence that the user watched illegal video content. From a different point of view, copyright infringement occurs when a malicious user restores video stream and share it to another site. In this paper, we selected 23 online streaming services that are widely used both at home and abroad. After streaming videos, we tested whether we can recover original video using cache files stored on the PC or not. As a result, the paper found that in most sites we can restore the original video by reconstructing cache files. Furthermore, this study also discussed methodologies for preventing copyright infringement in online streaming service.

• Journal of Korea Multimedia Society
• /
• v.15 no.9
• /
• pp.1126-1132
• /
• 2012

To enhance network efficiency, CCN allow intermediate network nodes between a content consumer and a content publisher to temporarily cache transmitted contents. Then the network nodes immediately return back the cached contents to another consumers when the nodes receives relevant contents request messages from the consumers. For that, CCN utilizes hierarchical content names to forward a request message as well as a response message. However, such content names semantically contain much information about domain/user as well as content itself. So it is possible to invade users' privacy. In this paper, we first review both the problem of CCN name in the view point of privacy and proposed schemes. Then we propose an improved name management scheme for users' privacy preservation.

• Journal of Information Processing Systems
• /
• v.18 no.2
• /
• pp.245-257
• /
• 2022

In the Internet of Things (IoT) era, the types of devices used by one user are becoming more diverse and the number of devices is also increasing. However, a forensic investigator is restricted to exploit or collect all the user's devices; there are legal issues (e.g., privacy, jurisdiction) and technical issues (e.g., computing resources, the increase in storage capacity). Therefore, in the digital forensics field, it has been a challenge to acquire information that remains on the devices that could not be collected, by analyzing the seized devices. In this study, we focus on the fact that multiple devices share data through account synchronization of the online platform. We propose a novel way of identifying the user's interest through analyzing the remnants of targeted advertising which is provided based on the visited websites or search terms of logged-in users. We introduce a detailed methodology to pick out the targeted advertising from cache data and infer the user's interest using deep learning. In this process, an improved learning model considering the unique characteristics of advertisement is implemented. The experimental result demonstrates that the proposed method can effectively identify the user interest even though only one device is examined.

• Journal of Korea Multimedia Society
• /
• v.11 no.3
• /
• pp.404-413
• /
• 2008

As toward a ubiquitous society, a lot of methods have been proposed to protect personal privacy. Smart Cards with CPU and Memory are widely being used to implement the methods. The use of Java Card is also gradually getting expanded into more various applications. Because there is no standards in Java Card File System, Generally, Java Card File System follows the standards of Smart Card File System. However, one of disadvantages of the Java Card File System using a standard of Smart Card File System is that inefficient memory use and increasing processing time are caused by redundancy of data and program codes. In this paper, a File Cache method and a Direct Access method are proposed to solve the problems. The proposed methods are providing efficient memory use and reduced processing time by reduce a program codes.

• Journal of KIISE:Software and Applications
• /
• v.30 no.9
• /
• pp.843-849
• /
• 2003

Web usage mining is the technique of data mining that analyzes web users' usage patterns by large web log. To use the web usage mining technique, we have to classify correctly users and users session in preprocessing, but can't classify them completely by only log files with standard web log format. To classify users and user session there are many problems like local cache, firewall, ISP, user privacy, cookey etc., but there isn't any definite method to solve the problems now. Especially local cache problem is the most difficult problem to classify user session which is used as input in web mining systems. In this paper we propose a heuristic method which solves local cache problem by using only click stream data of server side like referrer log, agent log and access log, classifies user sessions and completes session.

• Journal of Korea Multimedia Society
• /
• v.17 no.6
• /
• pp.697-705
• /
• 2014

For enhancing network efficiency, content-centric networking (CCN) allows network nodes to temporally cache a transmitted response message(Data) and then to directly respond to a request message (Interest) for previously cached contents. Also, CCN is designed to utilize a hierarchical content-name for transmitting Interest/Data instead of a host identity like IP address. This content-name included in Interest/Data reveals both content information itself and the structure of network domain of a content source which is needed for transmitting Interest/Data. To make matters worse, This content-name is human-readable like URL. Hence, through analyzing the content-name in Interest/Data, it is possible to analyze the creator of the requested contents. Also, hosts around the requester can analyze contents which are asked by the requester. Hence, for securely implementing CCN, it is essentially needed to make the content-name illegible. In this paper, we propose content-name encoding schemes for CCN so as to make the content-name illegible and evaluate the performance of our proposal.

• Journal of Korea Multimedia Society
• /
• v.16 no.8
• /
• pp.954-961
• /
• 2013

To enhance the efficiency of network, content-centric networking (CCN), one of future Internet architectures, allows network nodes to temporally cache transmitted contents and then to directly respond to request messages which are relevant to previously cached contents. Also, since CCN uses a hierarchical content-name, not a host identity like source/destination IP address, for request/response packet routing and CCN request message does not include requester's information for privacy protection, contents-providers/ network nodes can not identify practical requesters sending request messages. So to send back relevant contents, network nodes in CCN records both a request message and its incoming interfaces on Pending Interest Table (PIT). Then the devices refer PIT to return back a response message. If PIT is exhausted, the device can not normally handle request/response messages anymore. Hence, it is needed to detect/react attack to exhaust PIT. Hence, in this paper, we propose improved detection/reaction schemes against attacks to exhaust PIT. In practice, for fine-grained control, this proposal is applied to each incoming interface. Also, we propose the message framework to control attack traffic and evaluate the performance of our proposal.