Low-Latency Mix Networks for Anonymous Communication
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UC Santa Barbara UC Santa Barbara Electronic Theses and Dissertations
UC Santa Barbara UC Santa Barbara Electronic Theses and Dissertations Title A Web of Extended Metaphors in the Guerilla Open Access Manifesto of Aaron Swartz Permalink https://escholarship.org/uc/item/6w76f8x7 Author Swift, Kathy Publication Date 2017 Peer reviewed|Thesis/dissertation eScholarship.org Powered by the California Digital Library University of California UNIVERSITY OF CALIFORNIA Santa Barbara A Web of Extended Metaphors in the Guerilla Open Access Manifesto of Aaron Swartz A dissertation submitted in partial satisfaction of the requirements for the degree Doctor of Philosophy in Education by Kathleen Anne Swift Committee in charge: Professor Richard Duran, Chair Professor Diana Arya Professor William Robinson September 2017 The dissertation of Kathleen Anne Swift is approved. ................................................................................................................................ Diana Arya ................................................................................................................................ William Robinson ................................................................................................................................ Richard Duran, Committee Chair June 2017 A Web of Extended Metaphors in the Guerilla Open Access Manifesto of Aaron Swartz Copyright © 2017 by Kathleen Anne Swift iii ACKNOWLEDGEMENTS I would like to thank the members of my committee for their advice and patience as I worked on gathering and analyzing the copious amounts of research necessary to -
People Are Either Too Fake Or Too Real'': Opportunities And
Behavior in Online Communities CHI 2017, May 6–11, 2017, Denver, CO, USA “People Are Either Too Fake or Too Real”: Opportunities and Challenges in Tie-Based Anonymity Xiao Ma Nazanin Andalibi Louise Barkhuus Jacobs Institute, Cornell Tech College of Computing and The IT University of New York, NY, USA Informatics, Drexel University Copenhagen [email protected] Philadelphia, PA, USA Copenhagen, Denmark [email protected] [email protected] Mor Naaman Jacobs Institute, Cornell Tech New York, NY, USA [email protected] ABSTRACT affected social interactions and dynamics in offline and on- In recent years, several mobile applications allowed individ- line environments [11, 27]. Anonymity allows people to feel uals to anonymously share information with friends and con- less constrained by the expectations of their everyday iden- tacts, without any persistent identity marker. The functions of tities [3, 25], which in turn allows more candid and honest these “tie-based” anonymity services may be notably differ- self-expressions [1, 43]. Anonymity also leads users to dis- ent than other social media services. We use semi-structured close more information [52], which may result in positive interviews to qualitatively examine motivations, practices and emotional outcomes for the person disclosing [45]. On the perceptions in two tie-based anonymity apps: Secret (now de- other hand, the lack of attribution and responsibility in anony- funct, in the US) and Mimi (in China). Among the findings, mous environments can encourage malicious behaviors such we show that: (1) while users are more comfortable in self- as trolling [33] and cyberbullying [5, 6, 34]. It is no wonder disclosure, they still have specific practices and strategies to that society in general, and HCI researchers in particular, have avoid or allow identification; (2) attempts for de-identification been fascinated with the topic of anonymity. -
Low-Cost Traffic Analysis Of
Low-Cost Traffic Analysis of Tor Steven J. Murdoch and George Danezis University of Cambridge, Computer Laboratory 15 JJ Thomson Avenue, Cambridge CB3 0FD United Kingdom {Steven.Murdoch,George.Danezis}@cl.cam.ac.uk Abstract Other systems, based on the idea of a mix, were de- veloped to carry low latency traffic. ISDN mixes [33] Tor is the second generation Onion Router, supporting propose a design that allows phone conversations to be the anonymous transport of TCP streams over the Inter- anonymised, and web-mixes [6] follow the same design pat- net. Its low latency makes it very suitable for common terns to anonymise web traffic. A service based on these tasks, such as web browsing, but insecure against traffic- ideas, the Java Anon Proxy (JAP)1 has been implemented analysis attacks by a global passive adversary. We present and is running at the University of Dresden. These ap- new traffic-analysis techniques that allow adversaries with proaches work in a synchronous fashion, which is not well only a partial view of the network to infer which nodes are adapted for the asynchronous nature of widely deployed being used to relay the anonymous streams and therefore TCP/IP networks [8]. greatly reduce the anonymity provided by Tor. Furthermore, The Onion Routing project has been working on stream- we show that otherwise unrelated streams can be linked level, low-latency, high-bandwidth anonymous communi- back to the same initiator. Our attack is feasible for the cations [35]. Their latest design and implementation, adversary anticipated by the Tor designers. Our theoreti- Tor [18], has many attractive features, including forward se- cal attacks are backed up by experiments performed on the curity and support for anonymous servers. -
Consensgx: Scaling Anonymous Communications Networks With
Proceedings on Privacy Enhancing Technologies ; 2019 (3):331–349 Sajin Sasy* and Ian Goldberg* ConsenSGX: Scaling Anonymous Communications Networks with Trusted Execution Environments Abstract: Anonymous communications networks enable 1 Introduction individuals to maintain their privacy online. The most popular such network is Tor, with about two million Privacy is an integral right of every individual in daily users; however, Tor is reaching limits of its scala- society [72]. With almost every day-to-day interaction bility. One of the main scalability bottlenecks of Tor and shifting towards using the internet as a medium, it similar network designs originates from the requirement becomes essential to ensure that we can maintain the of distributing a global view of the servers in the network privacy of our actions online. Furthermore, in light to all network clients. This requirement is in place to of nation-state surveillance and censorship, it is all avoid epistemic attacks, in which adversaries who know the more important that we enable individuals and which parts of the network certain clients do and do not organizations to communicate online without revealing know about can rule in or out those clients from being their identities. There are a number of tools aiming to responsible for particular network traffic. provide such private communication, the most popular In this work, we introduce a novel solution to this of which is the Tor network [21]. scalability problem by leveraging oblivious RAM con- Tor is used by millions of people every day to structions and trusted execution environments in order protect their privacy online [70]. -
Doswell, Stephen (2016) Measurement and Management of the Impact of Mobility on Low-Latency Anonymity Networks
Citation: Doswell, Stephen (2016) Measurement and management of the impact of mobility on low-latency anonymity networks. Doctoral thesis, Northumbria University. This version was downloaded from Northumbria Research Link: http://nrl.northumbria.ac.uk/30242/ Northumbria University has developed Northumbria Research Link (NRL) to enable users to access the University’s research output. Copyright © and moral rights for items on NRL are retained by the individual author(s) and/or other copyright owners. Single copies of full items can be reproduced, displayed or performed, and given to third parties in any format or medium for personal research or study, educational, or not-for-profit purposes without prior permission or charge, provided the authors, title and full bibliographic details are given, as well as a hyperlink and/or URL to the original metadata page. The content must not be changed in any way. Full items must not be sold commercially in any format or medium without formal permission of the copyright holder. The full policy is available online: http://nrl.northumbria.ac.uk/policies.html MEASUREMENT AND MANAGEMENT OF THE IMPACT OF MOBILITY ON LOW-LATENCY ANONYMITY NETWORKS S.DOSWELL Ph.D 2016 Measurement and management of the impact of mobility on low-latency anonymity networks Stephen Doswell A thesis submitted in partial fulfilment of the requirements of the University of Northumbria at Newcastle for the degree of Doctor of Philosophy Research undertaken in the Department of Computer Science and Digital Technologies, Faculty of Engineering and Environment October 2016 Declaration I declare that the work contained in this thesis has not been submitted for any other award and that it is all my own work. -
Threat Modeling and Circumvention of Internet Censorship by David Fifield
Threat modeling and circumvention of Internet censorship By David Fifield A dissertation submitted in partial satisfaction of the requirements for the degree of Doctor of Philosophy in Computer Science in the Graduate Division of the University of California, Berkeley Committee in charge: Professor J.D. Tygar, Chair Professor Deirdre Mulligan Professor Vern Paxson Fall 2017 1 Abstract Threat modeling and circumvention of Internet censorship by David Fifield Doctor of Philosophy in Computer Science University of California, Berkeley Professor J.D. Tygar, Chair Research on Internet censorship is hampered by poor models of censor behavior. Censor models guide the development of circumvention systems, so it is important to get them right. A censor model should be understood not just as a set of capabilities|such as the ability to monitor network traffic—but as a set of priorities constrained by resource limitations. My research addresses the twin themes of modeling and circumvention. With a grounding in empirical research, I build up an abstract model of the circumvention problem and examine how to adapt it to concrete censorship challenges. I describe the results of experiments on censors that probe their strengths and weaknesses; specifically, on the subject of active probing to discover proxy servers, and on delays in their reaction to changes in circumvention. I present two circumvention designs: domain fronting, which derives its resistance to blocking from the censor's reluctance to block other useful services; and Snowflake, based on quickly changing peer-to-peer proxy servers. I hope to change the perception that the circumvention problem is a cat-and-mouse game that affords only incremental and temporary advancements. -
Trolls Under the Bridge: Anonymous Online Comments and Gatekeeping in the Digital Realm
TROLLS UNDER THE BRIDGE: ANONYMOUS ONLINE COMMENTS AND GATEKEEPING IN THE DIGITAL REALM _______________________________________ A thesis presented to the faculty of the graduate school at the University of Missouri-Columbia ___________________________________________________________ in partial fulfillment of the requirements for the degree, master of arts ______________________________________________ by NOELLE M. STEELE Ryan J. Thomas, Thesis Supervisor DECEMBER 2013 The undersigned, appointed by the dean of the graduate school, have examined the thesis entitled TROLLS UNDER THE BRIDGE: ANONYMOUS ONLINE COMMENTS AND GATEKEEPING IN THE DIGITAL REALM presented by Noelle M. Steele, a candidate for the degree of master of arts, and hereby certify that, in their opinion, it is worthy of acceptance. __________________________________________ Dr. Ryan J. Thomas __________________________________________ Dr. Tim Vos ___________________________________________ Professor Joy Mayer ____________________________________________ Dr. Christina Wells ACKNOWLEDGEMENTS A special thank you to Sarah Smith-Frigerio for her unending encouragement, faithful guidance and witty responses that kept matters light when they might otherwise have been stressful. Many a graduate student would have lost their way without her prompt attention to every issue that cropped up and tireless dedication to resolving the problem. Endless thanks to my thesis chair, Dr. Ryan J. Thomas, for his attention to detail and refusal to allow me to settle for anything less than the most polished piece of work I could possibly produce. I owe the completion of this research to his persistence and enthusiasm for the project. And to the remainder of my thesis committee – Drs. Tim Vos and Christina Wells and Professor Joy Mayer – thank you for believing in my rough research idea and challenging me to refine it from the very beginning. -
The Community Industry: an Analysis of Reddit and /R/Socialism
THE COMMUNITY INDUSTRY: AN ANALYSIS OF REDDIT AND /R/SOCIALISM Richard Babb A Dissertation Submitted to the Graduate College of Bowling Green State University in partial fulfillment of the requirements for the degree of DOCTOR OF PHILOSOPHY May 2021 Committee: Radhika Gajjala, Advisor Samuel T McAbee, Graduate Faculty Representative Lara Lengel Yanqin Lu © 2021 Richard Babb All Rights Reserved iii ABSTRACT Radhika Gajjala, Advisor Social media is an increasingly important space for community formation and interactions. Coinciding with the rise of social media has been an increasing interest in leftist ideologies once outside the mainstream. This analysis seeks to understand the social media site Reddit.com’s enabling and constraining features on the community /r/socialism. Using the communicative theory of identity and Marxist media theory not only to look at Reddit and /r/socialism’s relationship, but five key functions of a media: capital-economic, media sales and media market function, commodity circulation, domination, and the audience. Employing a mixed-methods approach enabled various data to be analyzed and relationally understood. Qualitative content analysis was used to examine user’s salient topics and their uses for the community. Survey methods were deployed to the community to gather demographic data on the /r/socialism community and user opinions on the group’s relationship with Reddit. Finally, secondary documents were analyzed to provide greater context to the other findings. Findings from the content analysis of salient subjects showed a preference for contemporary capitalist critique, socialist quotations, and class issues. However, topics impacting women and other minority groups were light to nonexistent. -
Social Network Based Anonymous Communication in Tor Peng Zhou, Xiapu Luo, Ang Chen, and Rocky K
1 STor: Social Network based Anonymous Communication in Tor Peng Zhou, Xiapu Luo, Ang Chen, and Rocky K. C. Chang Department of Computing, The Hong Kong Polytechnic University, Hunghom, Hong Kong cspzhouroc,csxluo,csachen,csrchang @comp.polyu.edu.hk f g Abstract—Anonymity networks hide user identities with the help of relayed anonymity routers. However, the state-of-the-art anonymity networks do not provide an effective trust model. As a result, users cannot circumvent malicious or vulnerable routers, thus making them susceptible to malicious router based attacks (e.g., correlation attacks). In this paper, we propose a novel social network based trust model to help anonymity networks circumvent malicious routers and obtain secure anonymity. In particular, we design an input independent fuzzy model to determine trust relationships between friends based on qualitative and quantitative social attributes, both of which can be readily obtained from existing social networks. Moreover, we design an algorithm for propagating trust over an anonymity network. We integrate these two elements in STor, a novel social network based Tor. We have implemented STor by modifying the Tor’s source code and conducted experiments on PlanetLab to evaluate the effectiveness of STor. Both simulation and PlanetLab experiment results have demonstrated that STor can achieve secure anonymity by establishing trust-based circuits in a distributed way. Although the design of STor is based on Tor network, the social network based trust model can be adopted by other anonymity networks. Index Terms—Social Network, Anonymous Communication, Tor, Fuzzy Model F 1 INTRODUCTION alone can be easily bypassed by an attacker. -
Asphalion: Trustworthy Shielding Against Byzantine Faults
Asphalion: Trustworthy Shielding Against Byzantine Faults IVANA VUKOTIC, SnT, University of Luxembourg VINCENT RAHLI, University of Birmingham PAULO ESTEVES-VERÍSSIMO, SnT, University of Luxembourg Byzantine fault-tolerant state-machine replication (BFT-SMR) is a technique for hardening systems to tolerate arbitrary faults. Although robust, BFT-SMR protocols are very costly in terms of the number of required replicas (3f + 1 to tolerate f faults) and of exchanged messages. However, with “hybrid” architectures, where “normal” components trust some “special” components to provide properties in a trustworthy manner, the cost of using BFT can be dramatically reduced. Unfortunately, even though such hybridization techniques decrease the message/time/space complexity of BFT protocols, they also increase their structural complexity. Therefore, we introduce Asphalion, the first theorem prover-based framework for verifying implementations of hybrid systems and protocols. It relies on three novel languages: (1) HyLoE: a Hybrid Logic of Events to reason about hybrid fault models; (2) MoC: a Monadic Component language to implement systems as collections of interacting hybrid components; and (3) LoCK: a sound Logic Of events-based Calculus of Knowledge to reason about both homogeneous and hybrid systems at a high-level of abstraction (thereby allowing reusing proofs, and capturing the high-level logic of distributed systems). In addition, Asphalion supports compositional reasoning, e.g., through mechanisms to lift properties about trusted-trustworthy components, to the level of the distributed systems they are integrated in. As a case study, we have verified crucial safety properties (e.g., agreement) of several implementations of hybrid protocols. CCS Concepts: • Theory of computation → Logic and verification. -
Sok: a Consensus Taxonomy in the Blockchain Era*
SoK: A Consensus Taxonomy in the Blockchain Era* Juan A. Garay Aggelos Kiayias† Texas A&M University University of Edinburgh & IOHK [email protected] [email protected] Sunday 8th December, 2019 Abstract Consensus is arguably one of the most fundamental problems in distributed computing, playing also an important role in the area of cryptographic protocols as the enabler of a secure broadcast functionality. While the problem has a long and rich history and has been analyzed from many dif- ferent perspectives, recently, with the advent of blockchain protocols like Bitcoin, it has experienced renewed interest from a much wider community of researchers and has seen its application expand to various novel settings. One of the main issues in consensus research is the many different variants of the problem that exist as well as the various ways the problem behaves when different setup, computational assump- tions and network models are considered. In this work we perform a systematization of knowledge in the landscape of consensus research in the Byzantine failure model starting with the original formu- lation in the early 1980s up to the present blockchain-based new class of consensus protocols. Our work is a roadmap for studying the consensus problem under its many guises, classifying the way it operates in the various settings and highlighting the exciting new applications that have emerged in the blockchain era. 1 Introduction The consensus problem—reaching agreement distributedly in the presence of faults—has been exten- sively studied in the literature starting with the seminal work of Shostak, Pease and Lamport [PSL80, LSP82]. -
El Gamal Mix-Nets and Implementation of a Verifier
KTH Royal Institute of Technology School of Computer Science and Communication El Gamal Mix-Nets and Implementation of a Verifier SA104X Degree Project in Engineering Physics Erik Larsson ([email protected]) Carl Svensson ([email protected]) Supervisor: Douglas Wikstr¨om Abstract A mix-net is a cryptographic protocol based on public key cryptography which enables untraceable communication through a collection of nodes. One important application is electronic voting where it enables the construction of systems which satisfies many voting security requirements, including veri- fiability of correct execution. Verificatum is an implementation of a mix-net by Douglas Wikstr¨om. This report concerns the implementation of a verifier and evaluation of the implementation manual for the Verificatum mix-net. The purpose of the document is to enable third parties to convince themselves that the mix- net has behaved correctly without revealing any secret information. This implementation is a simple version of the verifier using the document and some test vectors generated by the mix-net. The document contains all information but there are still some possibilities for further clarification in order to make it comprehensible to a larger audience. Contents 1 Introduction 2 1.1 Verificatum . 2 1.2 Goals and Scope . 3 2 Background 3 2.1 El Gamal Cryptography . 3 2.1.1 Definition . 4 2.1.2 Security . 4 2.1.3 Properties . 5 2.2 Cryptographic Primitives . 6 2.2.1 Hash functions . 6 2.2.2 Pseudo Random Generators . 6 2.2.3 Random Oracles . 7 2.3 Mix Networks . 7 2.3.1 Overview . 7 2.3.2 El Gamal Mix-Nets .