338 research outputs found
Decentralized combinatorial optimization.
Combinatorial optimization is a widely-studied class of computational problems with many theoretical and real-world applications. Optimization problems are typically tackled using hardware and software controlled by the user. Optimization can be competitive where problems are solved by competing agents in isolation, or by groups sharing hardware and software in a distributed manner. Blockchain technology enables decentralized applications (DApps). Optimization as a DApp would be run in a trustless manner where participation in the system is voluntary and problem-solving is incentivized with bitcoin, ether, or other fungible tokens. Using a purpose-built blockchain introduces the problem of bootstrapping robust immutability and token value. This is solved by building a DApp as a smart-contract on top of an existing Turing-complete blockchain platform such as Ethereum. We propose a means of using Ethereum Virtual Machine smart contracts to automate the payout of cryptocurrency rewards for market-based voluntary participation in the solution of combinatorial optimization problems without trusted intermediaries. We suggest use of this method for optimization-as-a-service, automation of contests, and long-term recording of best-known solutions
A Network Topology Approach to Bot Classification
Automated social agents, or bots, are increasingly becoming a problem on
social media platforms. There is a growing body of literature and multiple
tools to aid in the detection of such agents on online social networking
platforms. We propose that the social network topology of a user would be
sufficient to determine whether the user is a automated agent or a human. To
test this, we use a publicly available dataset containing users on Twitter
labelled as either automated social agent or human. Using an unsupervised
machine learning approach, we obtain a detection accuracy rate of 70%
Electric routing and concurrent flow cutting
We investigate an oblivious routing scheme, amenable to distributed
computation and resilient to graph changes, based on electrical flow. Our main
technical contribution is a new rounding method which we use to obtain a bound
on the L1->L1 operator norm of the inverse graph Laplacian. We show how this
norm reflects both latency and congestion of electric routing.Comment: 21 pages, 0 figures. To be published in Springer LNCS Book No. 5878,
Proceedings of The 20th International Symposium on Algorithms and Computation
(ISAAC'09
How to run POSIX apps in a minimal picoprocess
Abstract We envision a future where Web, mobile, and desktop applications are delivered as isolated, complete software stacks to a minimal, secure client host. This shift imbues app vendors with full autonomy to maintain their apps' integrity. Achieving this goal requires shifting complex behavior out of the client platform and into the vendors' isolated apps. We ported rich, interactive POSIX apps, such as Gimp and Inkscape, to a spartan host platform. We describe this effort in sufficient detail to support reproducibility
How to run POSIX apps in a minimal picoprocess
Abstract We envision a future where Web, mobile, and desktop applications are delivered as isolated, complete software stacks to a minimal, secure client host. This shift imbues app vendors with full autonomy to maintain their apps' integrity. Achieving this goal requires shifting complex behavior out of the client platform and into the vendors' isolated apps. We ported rich, interactive POSIX apps, such as Gimp and Inkscape, to a spartan host platform. We describe this effort in sufficient detail to support reproducibility
Manipulating Scrip Systems: Sybils and Collusion
Game-theoretic analyses of distributed and peer-to-peer systems typically use
the Nash equilibrium solution concept, but this explicitly excludes the
possibility of strategic behavior involving more than one agent. We examine the
effects of two types of strategic behavior involving more than one agent,
sybils and collusion, in the context of scrip systems where agents provide each
other with service in exchange for scrip. Sybils make an agent more likely to
be chosen to provide service, which generally makes it harder for agents
without sybils to earn money and decreases social welfare. Surprisingly, in
certain circumstances it is possible for sybils to make all agents better off.
While collusion is generally bad, in the context of scrip systems it actually
tends to make all agents better off, not merely those who collude. These
results also provide insight into the effects of allowing agents to advertise
and loan money. While many extensions of Nash equilibrium have been proposed
that address collusion and other issues relevant to distributed and
peer-to-peer systems, our results show that none of them adequately address the
issues raised by sybils and collusion in scrip systems.Comment: 20 pages, 5 figures. To appear in the Proceedings of The First
Conference on Auctions, Market Mechanisms and Their Applications (AMMA '09
How to run POSIX apps in a minimal picoprocess
Abstract We envision a future where Web, mobile, and desktop applications are delivered as isolated, complete software stacks to a minimal, secure client host. This shift imbues app vendors with full autonomy to maintain their apps' integrity. Achieving this goal requires shifting complexity out of the client platform and replacing the required behavior inside the vendors' isolated apps. We ported rich, interactive POSIX apps, such as Gimp and Inkscape, to a spartan host platform. We describe this effort in sufficient detail to support reproducibility
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