Publications de Anwitaman Datta

A Generic Trust Framework For Large-Scale Open Systems Using Machine Learning

In many large-scale distributed systems and on the Web, agents need to interact with other unknown agents to carry out some tasks or transactions. The ability to reason about and assess the potential risks in carrying out such transactions is essential for ...

Wiley-Blackwell2014

Trust beyond reputation: A computational trust model based on stereotypes

Anwitaman Datta, Xin Liu

Models of computational trust support users in taking decisions. They are commonly used to guide users' judgements in online auction sites; or to determine quality of contributions in Web 2.0 sites. However, most existing systems require historical informa ...

Elsevier2013

Fuzzynet: Ringless Routing in a Ring-like Structured Overlay

Karl Aberer, Anwitaman Datta, Sarunas Girdzijauskas, Wojciech Galuba

Many structured overlay networks rely on a ring invariant as a core network connectivity element. The responsibility ranges of the participating peers and navigability principles (greedy routing) heavily depend on the ring structure. For correctness guaran ...

2011

Carrier transport and sensitivity issues in heterojunction with intrinsic thin layer solar cells on N-type crystalline silicon: A computer simulation study

Christophe Ballif, Anwitaman Datta, Père Roca i Cabarrocas

Heterojunction with intrinsic thin layer or HIT solar cells are considered favorable for large-scale manufacturing of solar modules, as they combine the high efficiency of crystalline silicon (c-Si) solar cells, with the low cost of amorphous silicon techn ...

American Institute of Physics2010

Structured Overlay For Heterogeneous Environments: Design and Evaluation of Oscar

Karl Aberer, Anwitaman Datta, Sarunas Girdzijauskas

Recent years have seen advances in building large internet-scale index structures, generally known as structured overlays. Early structured overlays realized distributed hash tables (DHTs) which are ill suited for anything but exact queries. The need to su ...

2010

Enabling Secure Secret Sharing in Distributed Online Social Networks

Sonja Buchegger, Karl Aberer, Anwitaman Datta

We study a new application of threshold-based secret sharing in a distributed online social network (DOSN), where users need a means to back up and recover their private keys in a network of untrusted servers. Using a simple threshold-based secret sharing ...

Ieee Computer Soc Press, Customer Service Center, Po Box 3014, 10662 Los Vaqueros Circle, Los Alamitos, Ca 90720-1264 Usa2009

Implementing a P2P Social Network - Early Experiences and Insights from PeerSoN

Sonja Buchegger, Anwitaman Datta

To address privacy concerns in Online Social Networks (OSNs), we propose to use a distributed, peer-to-peer approach coupled with encryption. To verify the feasibility of such an approach, we designed a two-tiered architecture and protocols that recreate t ...

2009

Optimal caching for first-order query load-balancing in decentralized index structures

Karl Aberer, Anwitaman Datta, Wolfgang Nejdl

Springer2007

Query-load balancing in structured overlays

Karl Aberer, Anwitaman Datta, Roman Schmidt

Query-load (forwarding and answering) balancing in structured overlays is one of the most critical and least studied problems. It has been assumed that caching heuristics can take care of it. We expose that caching, while necessary, is not in itself suffic ...

2007

Oscar: A Data-Oriented Overlay For Heterogeneous Environments

Karl Aberer, Anwitaman Datta, Sarunas Girdzijauskas

Quite a few data-oriented overlay networks have been designed in recent years. These designs often (implicitly) assume various homogeneity which seriously limit their usability in real world. In this paper we present some performance results of the Oscar o ...

2007

The challenges of merging two similar structured overlays: A tale of two networks

Karl Aberer, Anwitaman Datta

Structured overlay networks is an important and interesting primitive that can be used by diverse peer-to-peer applications. Multiple overlays can result either because of network partitioning or (more likely) because different groups of peers build such o ...

Springer2006

SoS: self-organizing substrates

Anwitaman Datta

Large-scale networked systems often, both by design or chance exhibit self-organizing properties. Understanding self-organization using tools from cybernetics, particularly modeling them as Markov processes is a first step towards a formal framework which ...

EPFL2006

Internet-scale storage systems under churn - A study of the steady state using Markov models

Karl Aberer, Anwitaman Datta

Content storage in a distributed collaborative environment uses redundancy for better resilience and thus provides good availability and durability. In a peer-to-peer environment, where peers continuously leave and rejoin the network, various lazy strategi ...

IEEE Computer Society2006

Oscar: Small-world overlay for realistic key distributions

Karl Aberer, Anwitaman Datta, Sarunas Girdzijauskas

The research on P2P systems which support skewed key distributions has rapidly advanced in the recent years. Yet, the assumptions on the skews we are dealing with remained pretty simple: most of the existing literature assumes simple monotonous key distrib ...

2006

A decentralized public key infrastructure for customer-to-customer e-commerce

Karl Aberer, Anwitaman Datta, Manfred Hauswirth

Inderscience Publishers2005

Efficient, self-contained handling of identity in Peer-to-Peer systems

Karl Aberer, Anwitaman Datta, Manfred Hauswirth

Identification is an essential building block for many services in distributed information systems. The quality and purpose of identification may differ, but the basic underlying problem is always to bind a set of attributes to an identifier in a unique an ...

2004

A Query-Adaptive Partial Distributed Hash Table for Peer-to-Peer Systems

Karl Aberer, Anwitaman Datta, Fabius Klemm

2004

Autonomous Gossiping: A self-organizing epidemic algorithm for selective information dissemination in mobile ad-hoc networks

Karl Aberer, Anwitaman Datta

We introduce autonomous gossiping (A/G), a new genre epidemic algorithm for selective dissemination of information in contrast to previous usage of epidemic algorithms which flood the whole network. A/G is a paradigm which suits well in a mobile ad-hoc net ...

2004

Autonomous Gossiping: A Self-Organizing Epidemic Algorithm for Selective Information Dissemination in Wireless Mobile Ad-Hoc Networks

Karl Aberer, Anwitaman Datta

2004

Separating Business Process from User Interaction in Web-Based Information Commerce

Zoran Despotovic, Karl Aberer, Anwitaman Datta

In Web-based information commerce it is diffcult to disentangle presentation from process logic, and sometimes even data is not separate from the presentation. Consequently, it becomes crucial to define an abstract model for business processes and their ma ...

2003