scispace - formally typeset
Search or ask a question
Author

Sven Östring

Bio: Sven Östring is an academic researcher from University of Cambridge. The author has contributed to research in topics: Vehicular ad hoc network & Wireless ad hoc network. The author has an hindex of 3, co-authored 3 publications receiving 367 citations.

Papers
More filters
Journal ArticleDOI
01 Aug 2004
TL;DR: The model incorporates incentives for users to act as transit nodes on multi-hop paths and to be rewarded with their own ability to send traffic and illustrates the way in which network resources are allocated to users according to their geographical position.
Abstract: This paper explores a model for the operation of an ad hoc mobile network. The model incorporates incentives for users to act as transit nodes on multi-hop paths and to be rewarded with their own ability to send traffic. The paper explores consequences of the model by means of fluid-level simulations of a network and illustrates the way in which network resources are allocated to users according to their geographical position.

301 citations

Book ChapterDOI
29 Mar 2004
TL;DR: A framework for providing incentives for honest participation in global-scale distributed trust management infrastructures is introduced and an honesty metric is developed which can indicate the accuracy of feedback.
Abstract: In this paper, we introduce a framework for providing incentives for honest participation in global-scale distributed trust management infrastructures. Our system can improve the quality of information supplied by these systems by reducing free-riding and encouraging honesty. Our approach is twofold: (1) we provide rewards for participants that advertise their experiences to others, and (2) impose the credible threat of halting the rewards, for a substantial amount of time, for participants who consistently provide suspicious feedback. For this purpose we develop an honesty metric which can indicate the accuracy of feedback.

65 citations

Journal ArticleDOI
01 Jul 2004
TL;DR: The paper explores some of the trust questions that arise in this problem space and conjectures that the very structure of a peer organisation may have some hidden benefits for trust re-enforcement, that have been previously explored.
Abstract: This paper explores the extension of a model for the operation of an ad hoc mobile network to more general providerless networks, such as peer-to-peer systems. The model incorporates incentives for users to act as transit nodes on multi-hop paths and to be rewarded with their own ability to send traffic. The paper explores some of the trust questions that arise in this problem space and conjectures that the very structure of a peer organisation may have some hidden benefits for trust re-enforcement, that have not been previously explored (to our knowledge).

6 citations


Cited by
More filters
Proceedings ArticleDOI
17 May 2004
TL;DR: This work model the P2P system using the Generalized Prisoner's Dilemma, and proposes the Reciprocative decision function as the basis of a family of incentives techniques that can drive a system of strategic users to nearly optimal levels of cooperation.
Abstract: Lack of cooperation (free riding) is one of the key problems that confronts today's P2P systems. What makes this problem particularly difficult is the unique set of challenges that P2P systems pose: large populations, high turnover, a symmetry of interest, collusion, zero-cost identities, and traitors. To tackle these challenges we model the P2P system using the Generalized Prisoner's Dilemma (GPD),and propose the Reciprocative decision function as the basis of a family of incentives techniques. These techniques are fullydistributed and include: discriminating server selection, maxflow-based subjective reputation, and adaptive stranger policies. Through simulation, we show that these techniques can drive a system of strategic users to nearly optimal levels of cooperation.

633 citations

Journal ArticleDOI
TL;DR: This survey summary summarizes different modeling and solution concepts of networking games, as well as a number of different applications in telecommunications that make use of or can make useof networking games.

593 citations

01 Jan 2004
TL;DR: This paper proposes a fully distributed reputation system that can cope with false disseminated information and enables redemption and prevent the sudden exploitation of good reputation built over time by introducing re-evaluation and reputation fading.
Abstract: Reputation systems can be tricked by the spread of false reputation ratings, be it false accusations or false praise. Simple solutions such as exclusively relying on one’s own direct observations have drawbacks, as they do not make use of all the information available. We propose a fully distributed reputation system that can cope with false disseminated information. In our approach, everyone maintains a reputation rating and a trust rating about everyone else that they care about. From time to time first-hand reputation information is exchanged with others; using a modified Bayesian approach we designed and present in this paper, only second-hand reputation information that is not incompatible with the current reputation rating is accepted. Thus, reputation ratings are slightly modified by accepted information. Trust ratings are updated based on the compatibility of second-hand reputation information with prior reputation ratings. Data is entirely distributed: someone’s reputation and trust is the collection of ratings maintained by others. We enable redemption and prevent the sudden exploitation of good reputation built over time by introducing re-evaluation and reputation fading.

555 citations

Book
20 Jun 2008
TL;DR: This survey provides a comprehensive discussion of the models, algorithms, analysis, and methodologies in this vast and growing literature of power control in cellular networks, including optimization theory, control theory, game theory, and linear algebra.
Abstract: Transmit power in wireless cellular networks is a key degree of freedom in the management of interference, energy, and connectivity. Power control in both the uplink and downlink of a cellular network has been extensively studied, especially over the last 15 years, and some of the results have enabled the continuous evolution and significant impact of the digital cellular technology. This survey provides a comprehensive discussion of the models, algorithms, analysis, and methodologies in this vast and growing literature. It starts with a taxonomy of the wide range of power control problem formulations, and progresses from the basic formulation to more sophisticated ones. When transmit power is the only set of optimization variables, algorithms for fixed SIR are presented first, before turning to their robust versions and joint SIR and power optimization. This is followed by opportunistic and non-cooperative power control. Then joint control of power together with beamforming pattern, base station assignment, spectrum allocation, and transmit schedule is surveyed\break one-by-one. Throughout the survey, we highlight the use of mathematical language and tools in the study of power control, including optimization theory, control theory, game theory, and linear algebra. Practical implementations of some of the algorithms in operational networks are discussed in the concluding section. As illustrated by the open problems presented at the end of most chapters, in the area of power control in cellular networks, there are still many under-explored directions and unresolved issues that remain theoretically challenging and practically important..

479 citations

Journal ArticleDOI
TL;DR: This article describes how various interactions in wireless ad hoc networks can be modeled as a game, which allows the analysis of existing protocols and resource management schemes, as well as the design of equilibrium-inducing mechanisms that provide incentives for individual users to behave in socially-constructive ways.
Abstract: The application of mathematical analysis to the study of wireless ad hoc networks has met with limited success due to the complexity of mobility and traffic models, the dynamic topology, and the unpredictability of link quality that characterize such networks. The ability to model individual, independent decision makers whose actions potentially affect all other decision makers renders game theory particularly attractive to analyze the performance of ad hoc networks. In this article we describe how various interactions in wireless ad hoc networks can be modeled as a game. This allows the analysis of existing protocols and resource management schemes, as well as the design of equilibrium-inducing mechanisms that provide incentives for individual users to behave in socially-constructive ways. We survey the recent literature on game theoretic analysis of ad hoc networks, highlighting its applicability to power control and waveform adaptation, medium access control, routing, and node participation, among others.

449 citations