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IEEE Communications Society Conference on Sensor and Ad Hoc Communications and Networks (SECON)

作者： Yaoming Gong Yanmin Zhu Jiadi Yu Shanghai Jiao Tong University Shanghai CN Shanghai Key Lab of Scalable Computing and Systems Shanghai China Department of Computer Science and Engineering Shanghai Jiao Tong University Shanghai China

Elevated roads are built worldwide to alleviate urban traffic congestions. An elevated road may overlap with the ground surface road. This poses a great challenge to auto navigation systems. It is particularly difficult for auto navigation systems to determine if an vehicle is running on an elevated road because altitude readings from GPS (Global Positioning systems) receivers are of low accuracy. Without correct positioning of elevated or surface roads, an auto navigation system may recommend wrong routes which may lead to serious traffic accidents or cause drivers' anxiety. In this paper, we design a smartphone-based system called DEEL for detecting road elevation as the vehicle moves on urban roads. HMM-based models are built to characterize the patterns of vehicle dynamics with respect to the elevation of the road that the vehicle is moving on. The system leverages smartphone sensors to sense the instantaneous vehicle dynamics, including the 3D acceleration, the speed, and the number of perceived GPS satellites. Based on the sensed dynamics, it determines whether the vehicle is running on an elevated road or not in an online fashion. We have successfully implemented our system in Android-based smartphones. Extensive experiments demonstrate the system achieves a high accuracy of 92.1% with strong robustness to variations of vehicles, drivers and roads.

关键词： Roads Vehicles Smart phones Acceleration Gravity Global Positioning System Sensors

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vINT: Hardware-Assisted Virtual Interrupt Remapping for SMP VM with Scheduling Awareness

vINT: Hardware-Assisted Virtual Interrupt Remapping for SMP ...

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IEEE International Conference on Cloud computing Technology and Science (CloudCom)

作者： Jian Li Ruhui Ma HaiBing Guan David S. L. Wei Shanghai Key Laboratory of Scalable Computing and Systems Shanghai Jiao Tong University Shanghai China Fordham University New York NY US

Symmetric Multi-Processing (SMP) virtual machine (VM), or virtual SMP for short, enables a single virtual machine to span multiple processors, thereby supporting the virtual machine to run resource-intensive applications. In addition to offering higher computing capacity, virtual SMP also offers the opportunity to alleviate the problem of unpredictable I/O responsiveness. To this end, we propose vINT (scheduling status based virtual INterrupt remapping adapTer), a scheme that leverages hardware-assisted interrupt mapping. vINT obtains high efficiency and flexibility by adding a lightweight module in virtual machine monitor (VMM) with no need of changing VMM scheduler and is transparent to guest OS. We implement the prototype in XEN 4.3.0 and conduct evaluations with both micro-benchmarks and macro-benchmarks. The experimental results show that vINT can increase the networking throughput by 5x and can reduce the required execute time of disk I/O by 17.5%, while introducing only a light overhead.

关键词： Virtual machining Processor scheduling Virtualization Delays Bridges Monitoring Cloud computing

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Comprehensive understanding of operation cost reduction using energy storage for IDCs

Comprehensive understanding of operation cost reduction usin...

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IEEE Annual Joint Conference: INFOCOM, IEEE Computer and Communications Societies

作者： Haihang Zhou Jianguo Yao Haibing Guan Xue Liu Shanghai Key Laboratory of Scalable Computing and Systems Shanghai Jiao Tong University Shanghai China School of Computer Science McGill University Montreal Canada

To reduce the operation cost incurred by the rapidly growing energy consumption in internet data centers (IDCs), more and more internet service providers have spontaneously started using energy storage in various forms. The approach of energy storage is used to store cheap electricity energy when the electricity price from smart gird is low or the renewable energy is used. There are two typical forms of energy storage equipped in many IDCs, i.e., the battery storage and thermal energy storage. Recent work shows the energy storage can significantly reduce the operation cost for IDCs. However, the cost of the energy storage devices are still at a high level, and it may increase the operation cost for IDCs. In this paper, we investigate the comprehensive understanding on the operation cost reduction for IDCs using the energy storage. To this end, we conduct a quantitative analysis on the normalized electricity price in the two energy storage forms. The experiments demonstrate that the cost of the storage devices and renewable energy supply are largely affected by the storage capacity and the location of data centers, and we conclude that it does not always reduce operation cost using energy storage for IDCs.

关键词： Batteries Optimization Smart grids Discharges (electric) Thermal energy Renewable energy sources

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On Maximizing Reliability of Lifetime Constrained Data Aggregation Tree in Wireless Sensor Networks

On Maximizing Reliability of Lifetime Constrained Data Aggre...

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International Conference on Parallel Processing (ICPP)

作者： Mengfan Shan Guihai Chen Fan Wu Xiaobing Wu Xiaofeng Gao Pan Wu Haipeng Dai State Key Laboratory for Novel Software Technology Nanjing University Nanjing China Shanghai Key Laboratory of Scalable Computing and Systems Shanghai Jiao Tong University China

Tree-based routing structures are widely used to gather data in wireless sensor networks. Along with tree structures, in-network aggregation is adopted to reduce transmissions, to save energy and to prolong the network lifetime. Most existing works that focus on the lifetime optimization for data aggregation do not take the link quality into consideration. In this paper, we study the problem of Maximizing Reliability of Lifetime Constrained data aggregation trees (MRLC) in WSNs. Considering the NP-completeness of the MRLC problem, we propose an algorithm, namely Iterative Relaxation Algorithm (IRA), to iteratively relax the optimization program and to find the aggregation tree subject to the lifetime bound with a sub-optimal cost. To adapt to the distributed nature of the WSNs in practice, we further propose a Prufer code based distributed updating protocol. Through extensive simulations, we demonstrate that IRA outperforms the best known related work in term of reliability.

关键词： Wireless sensor networks Reliability Energy consumption Data collection Approximation algorithms Wireless communication Approximation methods

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Resisting three-dimensional manipulations in distributed wireless spectrum auctions

Resisting three-dimensional manipulations in distributed wir...

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IEEE Annual Joint Conference: INFOCOM, IEEE Computer and Communications Societies

作者： Dan Peng Shuo Yang Fan Wu Guihai Chen Shaojie Tang Tie Luo Shanghai Key Laboratory of Scalable Computing and Systems Shanghai Jiao Tong University China Department of Information Systems University of Texas Dallas USA A * STAR Institute for Infocomm Research Singapore

Auctions are believed to be effective methods to solve the problem of wireless spectrum allocation. Existing spectrum auction mechanisms are all centralized and suffer from several critical drawbacks of the centralized systems, which motivates the design of distributed spectrum auction mechanisms. However, extending a centralized spectrum auction to a distributed one broadens the strategy space of agents from one dimension (bid) to three dimensions (bid, communication, and computation), and thus cannot be solved by traditional approaches from mechanism design. In this paper, we propose two distributed spectrum auction mechanisms, namely distributed VCG and FAITH. Distributed VCG implements the celebrated Vickrey-Clarke-Groves mechanism in a distributed fashion to achieve optimal social welfare, at the cost of exponential communication overhead. In contrast, FAITH achieves sub-optimal social welfare with tractable computation and communication overhead. We prove that both of the two proposed mechanisms achieve faithfulness, i.e., the agents' individual utilities are maximized, if they follow the intended strategies. We also implement FAITH and evaluate its performance in various setups. Evaluation results show that FAITH achieves superior performance compared with the Nash equilibrium based approach.

关键词： Channel allocation Resource management Wireless communication Cost accounting Nash equilibrium Interference Conferences

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FDRC: Flow-Driven Rule Caching Optimization in Software Defined Networking

FDRC: Flow-Driven Rule Caching Optimization in Software Defi...

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IEEE International Conference on Communications

作者： He Li Song Guo Chentao Wu Jie Li School of Computer Science and Engineering The University of Aizu Shanghai Key Laboratory of Scalable Computing and Systems Department of Computer Science & Engineering Shanghai Jiao Tong University

ISBN: (纸本)9781467364300

With the sharp growth of cloud services and their possible combinations, the scale of data center network traffic has an inevitable explosive increasing in recent years. Software defined network (SDN) provides a scalable and flexible structure to simplify network traffic management. It has been shown that Ternary Content Addressable Memory (TCAM) management plays an important role on the performance of SDN. However, previous literatures, in point of view on rule placement strategies, are still insufficient to provide high scalability for processing large flow sets with a limited TCAM size. So caching is a brand new method for TCAM management which can provide better performance than rule placement. In this paper, we propose FDRC, an efficient flow-driven rule caching algorithm to optimize the cache replacement in SDN-based networks. Different from the previous packet-driven caching algorithm, FDRC is characterized by trying to deal with the challenges of limited cache size constraint and unpredictable flows. In particular, we design a caching algorithm with low-complexity to achieve high cache hit ratio by prefetching and special replacement strategy for predictable and unpredictable flows, respectively. By conducting extensive simulations, we demonstrate that our proposed caching algorithm significantly outperforms FIFO and least recently used (LRU) algorithms under various network settings.

关键词： Flexible structures Prefetching Switches Silicon

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Resisting Three-Dimensional Manipulations in Distributed Wireless Spectrum Auctions

Resisting Three-Dimensional Manipulations in Distributed Wir...

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第13届全国博士生学术年会——物联网专题

作者： Dan Peng Shuo Yang Fan Wu Guihai Chen Shaojie Tang Tie Luo Shanghai Key Laboratory of Scalable Computing and Systems Shanghai Jiao Tong UniversityChina Department of Information Systems University of Texas at Dallas USA Institute for Infocomm Research A*STAR Singapore

Auctions are believed to be effective methods to solve the problem of wireless spectrum *** spectrum auction mechanisms are all centralized and suffer from several critical drawbacks of the centralized systems, which motivates the design of distributed spectrum auction ***, extending a centralized spectrum auction to a distributed one broadens the strategy space of agents from one dimension (bid) to three dimensions (bid,communication, and computation), and thus cannot be solved by traditional approaches from mechanism *** this paper, we propose two distributed spectrum auction mechanisms, namely distributed VCG and *** VCG implements the celebrated Vickrey-Clarke-Groves mechanism in a distributed fashion to achieve optimal social welfare, at the cost of exponential communication *** contrast,FAITH achieves sub-optimal social welfare with tractable computation and communication *** prove that both of the two proposed mechanisms achieve faithfulness, i.e., the agents' individual utilities are maximized, if they follow the intended *** also implement FAITH and evaluate its performance in various *** results show that FAITH achieves superior performance compared with the Nash equilibrium based approach.

关键词： Distributed Algorithmic Mechanism Design Wireless Spectrum Allocation

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Delay-constrained data aggregation in VANETs

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IEEE Transactions on Vehicular Technology 2015年第5期64卷 2097-2107页

作者： Zhu, Yanmin Zhao, Qingwen Zhang, Qian Department of Computer Science and Engineering Shanghai Jiao Tong University Shanghai200240 China Shanghai Key Lab of Scalable Computing and Systems Shanghai Jiao Tong University Shanghai200240 China Department of Computer Science and Engineering Hong Kong University of Science and Technology Kowloon Hong Kong

Data aggregation has been recognized as an effective technique for reducing communication costs while obtaining useful aggregated information. In this paper, we study the crucial problem of delay-constrained data aggregation in vehicular ad hoc networks (VANETs), which has not been well studied in the literature. With the analysis based on real traces, we observe that there is heterogeneity with node contact patterns, which indicates that some nodes contact other nodes more frequently. Motivated by this observation, we propose an approach called aTree. The centralized aTree first constructs a data aggregation tree based on the shortest path tree and then assigns a waiting time budget to each node on the tree based on dynamic programming. We further develop a distributed aTree, in which a shortest path tree is built in a distributed fashion, and nodes determine their waiting time budgets collaboratively. We have performed extensive simulations on real taxi traces, and results show that our aTree schemes incur much lower transmission overhead while achieving the same performance compared with other schemes. © 1967-2012 IEEE.

关键词： Dynamic programming

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SMe: explicit & implicit constrained-space probabilistic threshold range queries for moving objects

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GeoInformatica 2015年第1期20卷 19-58页

作者： Zhi-Jie Wang Bin Yao Reynold Cheng Xiaofeng Gao Lei Zou Haibing Guan Minyi Guo Shanghai Key Laboratory of Scalable Computing and Systems Department of Computer Science and Engineering Shanghai Jiao Tong University Shanghai China Department of Computer Science University of Hong Kong Hongkong China Institute of Computer Science and Technology Peking University Beijing China

This paper studies the constrained-space probabilistic threshold range query (CSPTRQ) for moving objects, where objects move in a constrained-space (i.e., objects are forbidden to be located in some specific areas), and objects’ locations are uncertain. We differentiate two forms of CSPTRQs: explicit and implicit ones. Specifically, for each moving object o, we model its location uncertainty as a closed region, u, together with a probability density function. We also model a query range, R, as an arbitrary polygon. An explicit query can be reduced to a search (over all the u) that returns a set of tuples in form of (o, p) such that p ≥ p t , where p is the probability of o being located in R, and 0≤p t ≤ 1 is a given probabilistic threshold. In contrast, an implicit query returns only a set of objects (without attaching the specific probability information), whose probabilities being located in R are higher than p t . The CSPTRQ is a variant of the traditional probabilistic threshold range query (PTRQ). As objects moving in a constrained-space are common, clearly, it can also find many applications. At the first sight, our problem can be easily tackled by extending existing methods used to answer the PTRQ. Unfortunately, those classical techniques are not well suitable for our problem, due to a set of new challenges. Another method used to answer the constrained-space probabilistic range query (CSPRQ) can be easily extended to tackle our problem, but a simple adaptation of this method is inefficient, due to its weak pruning/validating capability. To solve our problem, we develop targeted solutions that are easy-to-understand and also easy-to-implement. Our central idea is to swap the order of geometric operations and to compute the appearance probability in a multi-step manner. We demonstrat

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A Distributed Approximation for Multi-Hop Clustering Problem in Wireless Sensor Networks

A Distributed Approximation for Multi-Hop Clustering Problem...

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IEEE Global Communications Conference

作者： Xudong Zhu Jun Li Xiaofeng Gao Fan Wu Guihai Chen Athanasios V. Vasilakos Shanghai Key Laboratory of Scalable Computing and Systems Department of Computer Science and Engineering Shanghai Jiao Tong University Dept of Computer Science Electrical and Space Engineering Lulea University of Technology

ISBN: (纸本)9781479959532

In wireless sensor networks (WSNs), there is no pre-defined infrastructure. Nodes need to frequently flood messages to discover routes, which badly decreases the network performance. To overcome such drawbacks, WSNs are often grouped into several disjointed clusters, each with a representative cluster head (CH) in charge of the routing process. In order to further improve the efficiency of WSNs, it is crucial to find a cluster partition with minimum number of clusters and the distance between each node to its corresponding CH can be bounded by a constant number of hops. Finding such a partition is defined as minimum d-hop cluster head set (d-MCHS) problem, which is proved to be NP-hard. In this paper, we propose a distributed approximation algorithm, named d~2-Cluster, to address d-MCHS problem and prove that the approximation ratio of d~2-Cluster under unit disk graph (UDG) is a constant factor λ which is related to d. To the best of our knowledge, it is the first constant approximation ratio for d-MDS problem in UDG.

关键词： Spread spectrum communication Wireless sensor networks UNG gene Approximation algorithms routing process cluster head approximation Nondeterministic polynomial-time hard hydrated carbon mutual exclusion

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