Mudhakar Srivatsa

Learn More
Reputation systems have been popular in estimating the trustworthiness and predicting the future behavior of nodes in a large-scale distributed system where nodes may transact with one another without prior knowledge or experience. One of the fundamental challenges in distributed reputation management is to understand vulnerabilities and develop mechanisms(More)
Location-based services, which employ data from smartphones, vehicles, etc., are growing in popularity. To reduce the threat that shared location data poses to a user's privacy, some services anonymize or obfuscate this data. In this paper, we show these methods can be effectively defeated: a set of location traces can be deanonymized given an easily(More)
A number of recent applications have been built on distributed hash tables (DHTs) based overlay networks. Almost all DHT-based schemes employ a tight deterministic data placement and ID mapping schemes. This feature on one hand provides assurance on location of data if it exists, within a bounded number of hops, and on the other hand, opens doors for(More)
In this paper, we study the quantification, practice, and implications of structural data (e.g., social data, mobility traces) De-Anonymization (DA). First, we address several open problems in structural data DA by quantifying perfect and (1-ε)-perfect structural data DA}, where ε is the error tolerated by a DA scheme. To the best of our(More)
Disruption Tolerant Networks (DTNs) are characterized by the low node density, unpredictable node mobility and lack of global network information. Most of current research efforts in DTNs focus on data forwarding, but only limited work has been done on providing effective data access to mobile users. In this paper, we propose a novel approach to support(More)
In a distributed Web service integration environment, the selection of Web services should be based on their reputation and quality-of-service (QoS). Various trust models for web services have been proposed to evaluate the reputation of Web services/service providers. Current mechanisms are based on tracing the feedbacks to the past behaviors of Web(More)
In both the commercial and defence sectors a compelling need is emerging for the rapid, yet secure, dissemination of information across traditional organisational boundaries. In this paper we present a novel trust management paradigm for securing pan-organisational information flows that aims to address the threat of information leakage. Our trust(More)
With fast-paced growth of digital data and exploding storage management costs, enterprises are looking for new ways to effectively manage their data. One such cost-effective paradigm is the cloud storage model also referred to as Storage-as-a-Service, in which enterprises <i>outsource</i> their storage to a storage service provider (SSP) by storing data(More)
This paper explores the idea of knowledge-based security policies, which are used to decide whether to answer queries over secret data based on an estimation of the querier’s (possibly increased) knowledge given the results. Limiting knowledge is the goal of existing information release policies that employ mechanisms such as noising, anonymization, and(More)
1 Serverless distributed computing has received significant attention from both the industry and the research community. Among the most popular applications are the wide area network file systems, exemplified by CFS [4], Farsite [1] and OceanStore [12]. These file systems store files on a large collection of untrusted nodes that form an overlay network.(More)