Browsing by Author "Huang, Jiun-Long"

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A Classification-Based Elephant Flow Detection Method using Application Round on SDN Environments
(2017-01-01)
Huang, Yuan-Hao
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Shih, Wen-Yueh
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Huang, Jiun-Long
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資訊工程學系
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Department of Computer Science
We propose in this paper a classification-based elephant flow detection method for SDN environments. The proposed elephant flow detection method consists of two classifiers running on the switch and the controller, respectively. For better performance, the concept of application round is used to build the classifier running on the controller. Experimental results show that our elephant flow detection method is able to obtain high recall and F-measure.
A Conditional Access System with Efficient Key Distribution and Revocation for Mobile Pay-TV Systems
(2013-06-01)
Yeh, Lo-Yao
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Huang, Jiun-Long
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資訊工程學系
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Department of Computer Science
Current mobile pay-TV systems have two types of Conditional Access Systems (CAS): group-key-based and public-key systems. The best feature of group-key-based systems is the ability to enjoy the broadcast nature in delivery multimedia contents, while the major advantage of public-key systems is consolidating the security foundation to withstand various attacks, such as collusion attacks. However, the problems of group-key-based systems include collusion attacks, lack of nonrepudiation, and troublesome key distribution. Even worse, the benefit of broadcast efficiency is confined to a group size of no more than 512 subscribers. For public-key systems, the poor delivery scalability is the major shortcoming because the unique private key feature is only suitable for one-to-one delivery. In this article, we introduce a scalable access control scheme to integrate the merits of broadcasting regardless of group size and sound security assurance, including fine-grained access control and collusion attack resistance. For subscriber revocation, a single message is broadcast to the other subscribers to get the updated key, thus significantly boosting subscriber revocation scalability. Due to mobile subscribers' dynamic movements, this article also analyzes the benefit of retransmission cases in our system. Through the performance evaluation and functionality comparison, the proposed scheme should be a decent candidate to enhance the security strength and transmission efficiency in a mobile pay-TV system.
A Gamma-based Regression for Winning Price Estimation in Real-Time Bidding Advertising
(2017-01-01)
Zhu, Wen-Yuan
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Shih, Wen-Yueh
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Lee, Ying-Hsuan
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Peng, Wen-Chih
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Huang, Jiun-Long
In Real-Time Bidding (RTB) advertising, estimating the winning price is an important task in evaluating the bid cost of bid requests in Demand-Side Platforms (DSPs). The prior works utilize censored linear regression for winning price estimation by considering both winning and losing bid records. In the traditional regression models, the winning price of each bid request is based on Gaussian distribution. However, the property of Gaussian distribution is not suitable for the winning price of each bid request, and it is hard to link the physical meaning of Gaussian distribution and the winning price. Therefore, in this paper, based on our observation and analysis, the winning price of each bid request is modeled by a unique gamma distribution with respect to its features. Then we propose a gamma-based censored linear regression with regularization for winning price estimation. To derive the parameters of our proposed complicated model based on bid records, our approach is to divide this hard problem into two sub-problems, which are easier to solve. In practice, we also provide four heuristic initial parameter settings that are able to greatly reduce the computation cost when deriving the parameters. The experimental results demonstrate that our approach is highly effective for estimating the winning price compared with the state-of-the-art approaches in three real datasets.
A Grid-based Successive Point-of-Interest Recommendation Method
(2017-01-01)
Gau, Hung-Yi
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Lu, Yi-Shu
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Huang, Jiun-Long
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資訊工程學系
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Department of Computer Science
With the increasing popularity of location-based social networks (LBSNs), users are able to share the pointof- interests (POIs) they visited by check-ins. By analyzing the users' historical check-in records, POI recommendation can help users get better visiting experiences by recommending POIs which users may be interested in. Although recent successive POI recommendation methods consider geographical influence by measuring distances among POIs, most of them ignore the influence of the regions where the POIs are located. Therefore, we propose a grid-based successive POI recommendation method, named UGSE-LR, to take the regional influence into consideration when recommending POIs. UGSE-LR first splits an area into grids for estimating regional influence. Then, UGSE-LR applies Edge-weighted Personalized PageRank (EdgePPR) for modeling the successive transitions among POIs. Finally, UGSE-LR fuses user preference, regional preference and successive transition preference into a unified recommendation framework. Experimental results on two real LBSN datasets show that our method is more accurate than the state-of-the-art successive POI recommendation methods in terms of precision and recall.
A Hybrid Preference-Aware Recommendation Algorithm for Live Streaming Channels
(2013-01-01)
Yang, Tzu-Wei
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Shih, Wen-Yuah
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Huang, Jiun-Long
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Ting, Wei-Chih
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Liu, Pin-Chuan
With the advances of video streaming technology, live streaming services also become more and more popular. However, there may be thousands of online channels at the same time, and most viewers are not willing to go through one by one for finding the channels they are interested in. In view of this, we propose a hybrid preference-aware recommendation algorithm to recommend channels to viewers. We use logs of a live streaming service, Twitch.tv, to measure the performance of our algorithm and other existing algorithms, and experimental results show that the accuracy of our algorithm is higher than those of other algorithms.
A practical authentication protocol with anonymity for wireless access networks
(2011-10-01)
Chen, Yen-Cheng
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Chuang, Shu-Chuan
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Yeh, Lo-Yao
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Huang, Jiun-Long
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資訊工程學系
The use of anonymous channel tickets was proposed for authentication in wireless environments to provide user anonymity and to probably reduce the overhead of re-authentications. Recently, Yang et al. proposed a secure and efficient authentication protocol for anonymous channel in wireless systems without employing asymmetric cryptosystems. In this paper, we will show that Yang et al.'s scheme is vulnerable to guessing attacks performed by malicious visited networks, which can easily obtain the secret keys of the users. We propose a new practical authentication scheme not only reserving the merits of Yang et al.'s scheme, but also extending some additional merits including: no verification table in the home network, free of time synchronization between mobile stations and visited networks, and without obsolete anonymous tickets left in visited networks. The proposed scheme is developed based on a secure one-way hash function and simple operations, a feature which is extremely fit for mobile devices. We provide the soundness of the authentication protocol by using VO logic. Copyright (C) 2010 John Wiley & Sons, Ltd.
A Proxy-Based Approach to Continuous Location-Based Spatial Queries in Mobile Environments
(2013-02-01)
Huang, Jiun-Long
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Huang, Chen-Che
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資訊工程學系
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Department of Computer Science
Caching valid regions of spatial queries at mobile clients is effective in reducing the number of queries submitted by mobile clients and query load on the server. However, mobile clients suffer from longer waiting time for the server to compute valid regions. We propose in this paper a proxy-based approach to continuous nearest-neighbor (NN) and window queries. The proxy creates estimated valid regions (EVRs) for mobile clients by exploiting spatial and temporal locality of spatial queries. For NN queries, we devise two new algorithms to accelerate EVR growth, leading the proxy to build effective EVRs even when the cache size is small. On the other hand, we propose to represent the EVRs of window queries in the form of vectors, called estimated window vectors (EWVs), to achieve larger estimated valid regions. This novel representation and the associated creation algorithm result in more effective EVRs of window queries. In addition, due to the distinct characteristics, we use separate index structures, namely EVR-tree and grid index, for NN queries and window queries, respectively. To further increase efficiency, we develop algorithms to exploit the results of NN queries to aid grid index growth, benefiting EWV creation of window queries. Similarly, the grid index is utilized to support NN query answering and EVR updating. We conduct several experiments for performance evaluation. The experimental results show that the proposed approach significantly outperforms the existing proxy-based approaches.
A QoS-aware and energy-conserving transcoding proxy using on-demand data broadcasting
(2007-08-01)
Huang, Jiun-Long
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Chen, Ming-Syan
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資訊工程學系
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Department of Computer Science
Most research works in transcoding proxies in mobile computing environments are on the basis of the traditional client-server architecture and do not employ the data broadcast technique. In addition, the issues of QoS provision and energy conservation are also not addressed in the prior studies. In view of this, we design in this paper a QoS-aware and energy-conserving transcoding proxy by utilizing the on-demand broadcasting technique. We first propose a QoS-aware and energy-conserving transcoding proxy architecture, abbreviated as QETP, and model it as a queuing network consisting of three queues. By analyzing the queuing network, three lemmas are derived to estimate the load of these queues. We then propose a version decision policy and a service admission control scheme to provide QoS in QETP. The derived lemmas are used to guide the execution of the proposed version decision policy and service admission control scheme to achieve the given QoS requirement. In addition, we also propose a data indexing method to reduce the power consumption of clients. To measure the performance of the proposed architecture, three experiments are conducted. Experimental results show that the average access time reduction of the proposed scheme over the traditional client-server architecture ranges from 45 percent to 75 percent. Experimental results also show that the proposed scheme is more scalable than the traditional client-server architecture and is able to effectively control the system load to attain the given QoS requirements. In addition, the proposed scheme is able to greatly reduce the average tuning time of clients at the cost of a slight increase ( around 5 percent in our experiments) in average access time.
A Skeleton and Gesture Based User Authentication System
(2015)
Lee, Hsueh-Fan
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Lu, Yi-Shu
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Huang, Jiun-Long
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Hu, Chih-Lin
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資訊工程學系
In this paper, we propose a skeleton and gesture-based user authentication system using depth cameras. When a user would like to register, our system will capture a user\'s skeleton and gesture information and store it into the database. When authenticating a user, our system will capture the user\'s skeleton and gesture information and compare it with the data stored in the database. Experimental results show that the combined use of skeleton and behavioral information is able to improve the accuracy of user authentication.
A virtual machine-based programming environment for rapid sensor application development
(2007)
Lin, Jui-Nan
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Huang, Jiun-Long
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資訊工程學系
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Department of Computer Science
In recent years, TinyOS and nesC are gradually becoming the de facto software development platform for implementing sensor applications. However developing sensor applications is difficult for programmers since the programming paradigm used in nesC is different from that used in other popular programming languages. In view of this, we propose in this paper a virtual machine-based programming environment for rapid sensor application development. With the proposed programming environment, sensor applications are implemented in TinyJava, which is a subset of Java programming language. Developing sensor applications is very similar as developing a traditional Java applications. Therefore, we believe that the proposed programming environment is able to speedup the development of sensor applications.
ABACS: An Attribute-Based Access Control System for Emergency Services over Vehicular Ad Hoc Networks
(2011-03-01)
Yeh, Lo-Yao
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Chen, Yen-Cheng
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Huang, Jiun-Long
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資訊工程學系
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Department of Computer Science
In this paper, we propose an Attribute-Based Access Control System (ABACS) for emergency services with security assurance over Vehicular Ad Hoc Networks (VANETs). ABACS aims to improve the efficiency of rescues mobilized via emergency communications over VANETs. By adopting fuzzy identity-based encryption, ABACS can select the emergency vehicles that can most appropriately deal with an emergency and securely delegate the authority to control traffic facilities to the assigned emergency vehicles. Using novel cryptographic preliminaries, ABACS realizes confidentiality of messages, prevention of collusion attacks, and fine-grained access control. As compared to the current PKI scheme, the computational delay and transmission overhead can be reduced by exploiting the advantages afforded by message broadcasting, which is heavily used in ABACS. The performance evaluation demonstrates that ABACS is a suitable candidate for realizing emergency services via VANETs.
ABAKA: An Anonymous Batch Authenticated and Key Agreement Scheme for Value-Added Services in Vehicular Ad Hoc Networks
(2011-01-01)
Huang, Jiun-Long
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Yeh, Lo-Yao
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Chien, Hung-Yu
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資訊工程學系
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Department of Computer Science
In this paper, we introduce an anonymous batch authenticated and key agreement (ABAKA) scheme to authenticate multiple requests sent from different vehicles and establish different session keys for different vehicles at the same time. In vehicular ad hoc networks (VANETs), the speed of a vehicle is changed from 10 to 40 m/s (36-144 km/h); therefore, the need for efficient authentication is inevitable. Compared with the current key agreement scheme, ABAKA can efficiently authenticate multiple requests by one verification operation and negotiate a session key with each vehicle by one broadcast message. Elliptic curve cryptography is adopted to reduce the verification delay and transmission overhead. The security of ABAKA is based on the elliptic curve discrete logarithm problem, which is an unsolved NP-complete problem. To deal with the invalid request problem, which may cause the batch verification fail, a detection algorithm has been proposed. Moreover, we demonstrate the efficiency merits of ABAKA through performance evaluations in terms of verification delay, transmission overhead, and cost for rebatch verifications, respectively. Simulation results show that both the message delay and message loss rate of ABAKA are less than that of the existing elliptic curve digital signature algorithm (ECDSA)-based scheme.
AIDOA: An adaptive and energy-conserving indexing method for on-demand data broadcasting systems
(2008-03-01)
Huang, Jiun-Long
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資訊工程學系
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Department of Computer Science
Since only a modest improvement in battery lifetime is expected in the next few years, energy conservation is raised as a key factor in the design of mobile devices. In view of this, we propose in this paper an energy-conserving on-demand data broadcasting system that employs the data indexing technique. Different from prior work, the power consumption of turning on and turning off the wireless network interfaces is considered. In addition, we also employ a server cache to reduce the effect of the time to retrieve data items from the corresponding data servers. Specifically, we first analyze the access and tuning times of data requests,. and propose an Adaptive Index and Data Organizing Algorithm (AIDOA) to adjust the degree of buckets according to the system workload. Several experiments are then conducted to evaluate the performance of algorithm AIDOA. The experimental results show that algorithm AIDOA is able to greatly reduce the power consumption at the cost of a slight increase in the average access time and dynamically adjust the index and data organization to adapt to the change of system workload.
ALM: An adaptive location management scheme for approximate location queries in wireless sensor networks
(2010-10-15)
Yeh, Lo-Yao
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Huang, Chen-Che
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Wu, Cheng-En
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Huang, Jiun-Long
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資訊工程學系
Location management is an important issue for object tracking applications of wireless sensor networks. Since locations obtained by most positioning techniques are inherently imprecise, users may send approximate location queries with precision constraints to trade for energy consumption of sensor nodes. Therefore, we propose an Adaptive Location Management scheme called ALM to process approximate location queries. ALM employs a two-tier storage architecture (i.e., centric storage node and local storage node) to facilitate approximate query resolving and to reduce the energy consumption of sensor nodes. We propose a storage node relocation and replication mechanism, which can create, remove replicas of storage nodes and adjust the positions of storage nodes according to the location queries and updates. As such, the number of forwarding location update and query messages is reduced by the proposed storage node relocation and replication mechanism, thereby conserving more energy. The experimental results show that compared with EASE (Xu et al. (2008) [18]), ALM is able to reduce the number of transmission messages and the energy consumption of sensor network, and prolong the network lifetime. (C) 2010 Elsevier B.V. All rights reserved.
ALM: An adaptive location management scheme for approximate location queries in wireless sensor networks
(2010-10-15)
Yeh, Lo-Yao
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Huang, Chen-Che
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Wu, Cheng-En
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Huang, Jiun-Long
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資訊工程學系
Location management is an important issue for object tracking applications of wireless sensor networks. Since locations obtained by most positioning techniques are inherently imprecise, users may send approximate location queries with precision constraints to trade for energy consumption of sensor nodes. Therefore, we propose an Adaptive Location Management scheme called ALM to process approximate location queries. ALM employs a two-tier storage architecture (i.e., centric storage node and local storage node) to facilitate approximate query resolving and to reduce the energy consumption of sensor nodes. We propose a storage node relocation and replication mechanism, which can create, remove replicas of storage nodes and adjust the positions of storage nodes according to the location queries and updates. As such, the number of forwarding location update and query messages is reduced by the proposed storage node relocation and replication mechanism, thereby conserving more energy. The experimental results show that compared with EASE (Xu et al. (2008) [18]), ALM is able to reduce the number of transmission messages and the energy consumption of sensor network, and prolong the network lifetime. (C) 2010 Elsevier B.V. All rights reserved.
An Efficient Algorithm for High Utility Sequential Pattern Mining
(2014-01-01)
Wang, Jun-Zhe
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Yang, Zong-Hua
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Huang, Jiun-Long
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資訊工程學系
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Department of Computer Science
High utility sequential pattern mining is to mine sequences with high utility (e. g. profits) but probably with low frequency. In some applications such as marketing analysis, high utility sequential patterns are usually more useful than sequential patterns with high frequency. In this paper, we devise two pruning strategies RSU and PDU, and propose HUS-Span algorithm based on these two pruning strategies to efficiently identify high utility sequential patterns. Experimental results show that HUS-Span algorithm outperforms prior algorithms by pruning more low utility sequences.
An Expected Win Rate-Based Real Time Bidding Strategy for Branding Campaign by the Model-Free Reinforcement Learning Model
(2020-01-01)
Shih, Wen-Yueh
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Lu, Yi-Shu
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Tsai, Hsiao-Ping
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Huang, Jiun-Long
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資訊工程學系
The bidding strategy plays the most important role to help the Demand Side Platforms (DSPs) making bidding decisions on a large number of bid requests in Real Time Bidding (RTB) to satisfy the different objectives of campaigns under the lifetime and budget constraints. In this paper, we focus on branding campaign whose objective is to obtain as many impressions as possible under the lifetime and budget constraints. To achieve the objectives of branding campaigns, we propose a novel expected win rate-based bidding strategy for branding campaign under the lifetime and budget constraints by utilizing a model-free reinforcement learning model. Specifically, to prevent missing good opportunities resulting from submitting extremely low bid prices, the concept of the base winning price is introduced to determine the lower bound of expected winning price. In addition, to obtain more impressions, the concept of the DSP-specified budget spending plan is proposed to determine the proper winning prices. The base expected win rate is then calculated based on the base winning price and the winning price determined by the DSP-specified budget spending plan. Since RTB is a dynamic environment, we propose a novel expected win rate-based bidding strategy named EWDQN which utilizes Deep Q Network (DQN) to dynamically determine the expected win rate according to the base expected win rate and the current status of the RTB market, and then determines the bid price according to the expected win rate. To the best of our knowledge, this is the first research applying the reinforcement learning technique on the bidding strategies for branding campaign. To measure the performance of EWDQN, several experiments are conducted on two real datasets. Experimental results show that EWDQN outperforms the-state-of-the-art bidding strategies for branding campaign in terms of the number of obtained impressions and CPM (cost per thousand impressions).
An expected win rate-based real-time bidding strategy for branding campaigns on display advertising
(2019-12-01)
Shih, Wen-Yueh
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Huang, Jiun-Long
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資訊工程學系
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Department of Computer Science
For branding campaigns, the demand-side platforms (DSPs) in real-time bidding (RTB) usually need to win as many impressions as possible to inform most audiences about the product messages under constraints on budgets, campaign lifetimes and budget spending plans. In this paper, we propose a novel bidding strategy by introducing the concept of expected win rate. With the proposed expected win rate-based bidding strategy, the DSP can dynamically adjust the expected win rate for each incoming bid request based on factors such as the predicted number of bid requests in the near future, the remaining budget and the remaining lifetime of the campaign. The experimental results show that the proposed bidding strategy has a lower cost per thousand impressions and cost per clicks than existing pacing model-based bidding strategies for branding campaigns with the same budgets and budget spending plans.
An Privacy-preserving Cross-organizational Authentication/Authorization/Accounting System using Blockchain Technology
(2018-01-01)
Lu, Peggy Joy
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Yeh, Lo-Yao
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Huang, Jiun-Long
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交大名義發表
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資訊工程學系
Thanks to the growth of cloud computing and network technology, different organizations might want to share data and resources between each other. However, cross-organizational authentication systems usually need a central control system, which must be fully trusted. Thus, we use blockchain technology to store the access control list of users due to its tamper-proof and decentralized feature. Our system also provides authentication/authorization/accounting functions by using a virtual coin exe_coin to achieve accounting function. The method of one-way hash chain is used to securely adapt to the transparency feature of blockchain. In authentication system, the transparency may lead to the linkability problem. In our scheme, attackers cannot get the linkability between the transactions and the particular user. To the best of our knowledge, our scheme is the first blockchain-based authentication system with the merits of unlinkability and accounting.
Automatic System for the Arrangement of Piano Reductions
(2009)
Chiu, Shih-Chuan
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Shan, Man-Kwan
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Huang, Jiun-Long
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資訊工程學系
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Department of Computer Science
Piano reduction is a process that arranges music for the piano by reducing the original music into the most basic components. In this study we present an automatic arrangement system for piano reduction that arranges music algorithmically for the piano while considering various roles of the piano in music. We achieve this by first analyzing the original music in order to determine the type of arrangement element performed by an instrument. Then each phrase is identified and is associated with a weighted importance value. At last, a phrase selection algorithm is proposed to select phrases with maximum importance to arrangement under the constraint of piano playability. Our experiments demonstrate that the proposed system has the ability to create piano arrangement.