Tor: the Second-Generation Onion Router
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A Generic Data Exchange System for F2F Networks
The Retroshare project The GXS system Decentralize your app! A Generic Data Exchange System for F2F Networks Cyril Soler C.Soler The GXS System 03 Feb. 2018 1 / 19 The Retroshare project The GXS system Decentralize your app! Outline I Overview of Retroshare I The GXS system I Decentralize your app! C.Soler The GXS System 03 Feb. 2018 2 / 19 The Retroshare project The GXS system Decentralize your app! The Retroshare Project I Mesh computers using signed TLS over TCP/UDP/Tor/I2P; I anonymous end-to-end encrypted FT with swarming; I mail, IRC chat, forums, channels; I available on Mac OS, Linux, Windows, (+ Android). C.Soler The GXS System 03 Feb. 2018 3 / 19 The Retroshare project The GXS system Decentralize your app! The Retroshare Project I Mesh computers using signed TLS over TCP/UDP/Tor/I2P; I anonymous end-to-end encrypted FT with swarming; I mail, IRC chat, forums, channels; I available on Mac OS, Linux, Windows. C.Soler The GXS System 03 Feb. 2018 3 / 19 The Retroshare project The GXS system Decentralize your app! The Retroshare Project I Mesh computers using signed TLS over TCP/UDP/Tor/I2P; I anonymous end-to-end encrypted FT with swarming; I mail, IRC chat, forums, channels; I available on Mac OS, Linux, Windows. C.Soler The GXS System 03 Feb. 2018 3 / 19 The Retroshare project The GXS system Decentralize your app! The Retroshare Project I Mesh computers using signed TLS over TCP/UDP/Tor/I2P; I anonymous end-to-end encrypted FT with swarming; I mail, IRC chat, forums, channels; I available on Mac OS, Linux, Windows. -
Pairing-Based Onion Routing with Improved Forward Secrecy ∗
Pairing-Based Onion Routing with Improved Forward Secrecy ∗ Aniket Kate Greg M. Zaverucha Ian Goldberg David R. Cheriton School of Computer Science University of Waterloo Waterloo, ON, Canada N2L 3G1 {akate,gzaveruc,iang}@cs.uwaterloo.ca Abstract This paper presents new protocols for onion routing anonymity networks. We define a provably secure privacy-preserving key agreement scheme in an identity-based infrastructure setting, and use it to forge new onion routing circuit constructions. These constructions, based on a user’s selection, offer immediate or eventual forward secrecy at each node in a circuit and require significantly less computation and communication than the telescoping mechanism used by Tor. Further, the use of the identity-based infrastructure also leads to a reduction in the required amount of authenticated directory information. Therefore, our constructions provide practical ways to allow onion routing anonymity networks to scale gracefully. Keywords: onion routing, Tor, pairing-based cryptography, anonymous key agreement, forward secrecy 1 Introduction Over the years, a large number of anonymity networks have been proposed and some have been implemented. Common to many of them is onion routing [RSG98], a technique whereby a message is wrapped in multiple layers of encryption, forming an onion. As the message is delivered via a number of intermediate onion routers (ORs), or nodes, each node decrypts one of the layers, and forwards the message to the next node. This idea goes back to Chaum [Cha81] and has been used to build both low- and high-latency communication networks. A common realization of an onion routing system is to arrange a collection of nodes that will relay traffic for users of the system. -
Anonymous Rate Limiting with Direct Anonymous Attestation
Anonymous rate limiting with Direct Anonymous Attestation Alex Catarineu Philipp Claßen Cliqz GmbH, Munich Konark Modi Josep M. Pujol 25.09.18 Crypto and Privacy Village 2018 Data is essential to build services 25.09.18 Crypto and Privacy Village 2018 Problems with Data Collection IP UA Timestamp Message Payload Cookie Type 195.202.XX.XX FF.. 2018-07-09 QueryLog [face, facebook.com] Cookie=966347bfd 14:01 1e550 195.202.XX.XX Chrome.. 2018-07-09 Page https://analytics.twitter.com/user/konark Cookie=966347bfd 14:06 modi 1e55040434abe… 195.202.XX.XX Chrome.. 2018-07-09 QueryLog [face, facebook.com] Cookie=966347bfd 14:10 1e55040434abe… 195.202.XX.XX Chrome.. 2018-07-09 Page https://booking.com/hotels/barcelona Cookie=966347bfd 16:15 1e55040434abe… 195.202.XX.XX Chrome.. 2018-07-09 QueryLog [face, facebook.com] Cookie=966347bfd 14:10 1e55040434abe… 195.202.XX.XX FF.. 2018-07-09 Page https://shop.flixbus.de/user/resetting/res Cookie=966347bfd 18:40 et/hi7KTb1Pxa4lXqKMcwLXC0XzN- 1e55040434abe… 47Tt0Q 25.09.18 Crypto and Privacy Village 2018 Anonymous data collection Timestamp Message Type Payload 2018-07-09 14 Querylog [face, facebook.com] 2018-07-09 14 Querylog [boo, booking.com] 2018-07-09 14 Page https://booking.com/hotels/barcelona 2018-07-09 14 Telemetry [‘engagement’: 0 page loads last week, 5023 page loads last month] More details: https://gist.github.com/solso/423a1104a9e3c1e3b8d7c9ca14e885e5 http://josepmpujol.net/public/papers/big_green_tracker.pdf 25.09.18 Crypto and Privacy Village 2018 Motivation: Preventing attacks on anonymous data collection Timestamp Message Type Payload 2018-07-09 14 querylog [book, booking.com] 2018-07-09 14 querylog [fac, facebook.com] … …. -
Hotspot Feature for Wi-Fi Clients with RADIUS User Authentication on Digi Transport
Application Note 56 Hotspot feature for Wi-Fi clients with RADIUS User Authentication on Digi TransPort. Digi Support November 2015 1 Contents 1 Introduction ......................................................................................................................................... 4 1.1 Outline ......................................................................................................................................... 4 1.2 Assumptions ................................................................................................................................ 4 1.3 Corrections .................................................................................................................................. 4 2 Version .................................................................................................................................................5 3 Configuration .......................................................................................................................................5 3.1 Mobile Interface Configuration .....................................................................................................5 3.2 Ethernet Interface Configuration ................................................................................................. 6 3.2.1 ETH 0 Configuration ................................................................................................................. 6 3.2.2 ETH 12 Logical Interface Configuration .................................................................................... -
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. -
Into the Reverie: Exploration of the Dream Market
Into the Reverie: Exploration of the Dream Market Theo Carr1, Jun Zhuang2, Dwight Sablan3, Emma LaRue4, Yubao Wu5, Mohammad Al Hasan2, and George Mohler2 1Department of Mathematics, Northeastern University, Boston, MA 2Department of Computer & Information Science, Indiana University - Purdue University, Indianapolis, IN 3Department of Mathematics and Computer Science, University of Guam, Guam 4Department of Mathematics and Statistics, University of Arkansas at Little Rock, AK 5Department of Computer Science, Georgia State University, Atlanta, GA [email protected], [email protected], [email protected], [email protected], [email protected], [email protected], [email protected], [email protected] Abstract—Since the emergence of the Silk Road market in Onymous" in 2014, a worldwide action taken by law enforce- the early 2010s, dark web ‘cryptomarkets’ have proliferated and ment and judicial agencies aimed to put a kibosh on these offered people an online platform to buy and sell illicit drugs, illicit behaviors [5]. Law enforcement interventions such as relying on cryptocurrencies such as Bitcoin for anonymous trans- actions. However, recent studies have highlighted the potential for Onymous, along with exit scams and hacks, have successfully de-anonymization of bitcoin transactions, bringing into question shut down numerous cryptomarkets, including AlphaBay, Silk the level of anonymity afforded by cryptomarkets. We examine a Road, Dream, and more recently, Wall Street [6]. Despite these set of over 100,000 product reviews from several cryptomarkets interruptions, new markets have continued to proliferate. The collected in 2018 and 2019 and conduct a comprehensive analysis authors of [7] note that there appears to be a consistent daily of the markets, including an examination of the distribution of drug sales and revenue among vendors, and a comparison demand of about $500,000 for illicit products on the dark web, of incidences of opioid sales to overdose deaths in a US city. -
Wikileaks and the Institutional Framework for National Security Disclosures
THE YALE LAW JOURNAL PATRICIA L. BELLIA WikiLeaks and the Institutional Framework for National Security Disclosures ABSTRACT. WikiLeaks' successive disclosures of classified U.S. documents throughout 2010 and 2011 invite comparison to publishers' decisions forty years ago to release portions of the Pentagon Papers, the classified analytic history of U.S. policy in Vietnam. The analogy is a powerful weapon for WikiLeaks' defenders. The Supreme Court's decision in the Pentagon Papers case signaled that the task of weighing whether to publicly disclose leaked national security information would fall to publishers, not the executive or the courts, at least in the absence of an exceedingly grave threat of harm. The lessons of the PentagonPapers case for WikiLeaks, however, are more complicated than they may first appear. The Court's per curiam opinion masks areas of substantial disagreement as well as a number of shared assumptions among the Court's members. Specifically, the Pentagon Papers case reflects an institutional framework for downstream disclosure of leaked national security information, under which publishers within the reach of U.S. law would weigh the potential harms and benefits of disclosure against the backdrop of potential criminal penalties and recognized journalistic norms. The WikiLeaks disclosures show the instability of this framework by revealing new challenges for controlling the downstream disclosure of leaked information and the corresponding likelihood of "unintermediated" disclosure by an insider; the risks of non-media intermediaries attempting to curtail such disclosures, in response to government pressure or otherwise; and the pressing need to prevent and respond to leaks at the source. AUTHOR. -
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]. -
The Economic Functioning of Online Drugs Markets
ISSN 2042-2695 CEP Discussion Paper No 1490 Revised August 2017 (Replaced July 2017 version) The Economic Functioning of Online Drugs Markets V. Bhaskar Robin Linacre Stephen Machin Abstract The economic functioning of online drug markets using data scraped from online platforms is studied. Analysis of over 1.5 million online drugs sales shows online drugs markets tend to function without the significant moral hazard problems that, a priori, one might think would plague them. Only a small proportion of online drugs deals receive bad ratings from buyers, and online markets suffer less from problems of adulteration and low quality that are a common feature of street sales of illegal drugs. Furthermore, as with legal online markets, the market penalizes bad ratings, which subsequently lead to significant sales reductions and to market exit. The impact of the well-known seizure by law enforcement of the original Silk Road and the shutdown of Silk Road 2.0 are also studied, together with the exit scam of the market leader at the time, Evolution. There is no evidence that these exits deterred buyers or sellers from online drugs trading, as new platforms rapidly replaced those taken down, with the online market for drugs continuing to grow. Keywords: dark web, drugs JEL codes:K42 This paper was produced as part of the Centre’s Communities Programme. The Centre for Economic Performance is financed by the Economic and Social Research Council. Acknowledgements Robin Linacre contributed to this paper in a personal capacity and in his own time. The research is not linked to any of his work for either the Sentencing Council or the Ministry of Justice. -
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. -
Privacy As Security
Privacy as Security Dr George Danezis Microsoft Research, Cambridge, UK. [email protected] Dr George Danezis Privacy as Security Key Thesis and Outline What is this talk about? I Explore the relations between notions of `privacy' and `traditional security'. I Key thesis: Privacy is better understood as security! How do we proceed? I Introduction to Privacy. I Revisiting security/privacy properties. Dr George Danezis Privacy as Security Scope Ground rules of this talk: I High-level: keep out the very technical details. Implementation issues, system specific, cryptography, statistics, standards. I Focus on technology and technology policy. There is also law, sociology, political science, and politics. I Look at privacy in the context of computer security Security properties, adversary models, security policies, . I A clear focus on the real world and its constraints. Dr George Danezis Privacy as Security Caricature of the debate: Security or Privacy \Privacy" important but. I . what about abuse and accountability? I . difficulties for Law Enforcement? I . copyright or libel? I (. what does a good, honest person has to hide anyway?) Established wisdom: I Need for a balance... I Control/limit dangerous technology (or research). I Result: Surveillance by design ! no privacy (often). Caricature conclusion: Security is most important! Dr George Danezis Privacy as Security Security and Privacy in Context A brief history of security, and where does privacy fit? I Early days (Pre-1970s): Security for the Government and Military. Focus on confidentiality properties. Some work on Tamper resistance, signal intelligence, . Keep secrets using computer security. I 70s to 90s: Commercial security and security for enterprises.