As one of the most popular cloud services, data storage has attracted great attention in recent research efforts. Key-value (k-v) stores have emerged as a popular option for storing and querying billions of key-value pairs. So far, existing methods have been deterministic. Providing such accuracy, however, comes at the cost of memory and CPU time. […]
Mathematical Programming Approach for Revenue Maximization in Cloud Federations
This paper assesses the benefits of cloud federation for cloud providers. Outsourcing and insourcing are explored as means to maximize the revenues of the providers involved in the federation. An exact method using a linear integer program is proposed to optimize the partitioning of the incoming workload across the federation members. A pricing model is […]
Joint Pricing and Capacity Planning in the IaaS Cloud Market
Cloud Computing In the cloud context, pricing and capacity planning are two important factors to the profit of the infrastructure-as-a-service (IaaS) providers. This paper investigates the problem of joint pricing and capacity planning in the IaaS provider market with a set of software-as-a-service (SaaS) providers, where each SaaS provider leases the virtual machines (VMs) from […]
TEES: An Efficient Search Scheme over Encrypted Data on Mobile Cloud
Cloud storage provides a convenient, massive, and scalable storage at low cost, but data privacy is a major concern that prevents users from storing files on the cloud trustingly. One way of enhancing privacy from data owner point of view is to encrypt the files before outsourcing them onto the cloud and decrypt the files […]
Search Rank Fraud and Malware Detection in Google Play
Fraudulent behaviors in Google Play, the most popular Android app market, fuel search rank abuse and malware proliferation. To identify malware, previous work has focused on app executable and permission analysis. In this paper, we introduce FairPlay, a novel system that discovers and leverages traces left behind by fraudsters, to detect both malware and apps […]
Bag-of-Discriminative-Words (BoDW) Representation via Topic Modeling
Many of the words in a given document either deliver facts (objective) or express opinions (subjective), respectively, depending on the topics they are involved in. For example, given a bunch of documents, the word “bug” assigned to the topic “order Hemiptera” apparently remarks one object (i.e., one kind of insects), while the same word assigned […]
A Systematic Approach to Clustering Whole Trajectories of Mobile Objects in Road Networks
Most of mobile object trajectory clustering analysis to date has been focused on clustering the location points or sub-trajectories extracted from trajectory data. This paper presents TRACEMOB, a systematic approach to clustering whole trajectories of mobile objects traveling in road networks. TRACEMOB as a whole trajectory clustering framework has three unique features. First, we design […]
Efficient Distance-Aware Influence Maximization in Geo-Social Networks
Given a social network G and a positive integer k, the influence maximization problem aims to identify a set of k nodes in G that can maximize the influence spread under a certain propagation model. As the proliferation of geo-social networks, location-aware promotion is becoming more necessary in real applications. In this paper, we study […]
Efficient Pattern-Based Aggregation on Sequence Data
A Sequence OLAP (S-OLAP) system provides a platform on which pattern-based aggregate (PBA) queries on a sequence database are evaluated. In its simplest form, a PBA query consists of a pattern template T and an aggregate function F. A pattern template is a sequence of variables, each is defined over a domain. Each variable is […]
Google Play Malware and Rank Fraud Detection
Fraudulent developers frequently exploit google play to hire teams of willing workers to commit fraud collectively, emulating realistic, spontaneous activities from unrelated people. This behavior is called “search rank fraud”. We present Fair-Play, a novel system that uncovers both malware and search rank fraud apps, by picking out trails those fraudsters leave behind. To identify […]