Practical Anonymous Networking?
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IPFS and Friends: a Qualitative Comparison of Next Generation Peer-To-Peer Data Networks Erik Daniel and Florian Tschorsch
1 IPFS and Friends: A Qualitative Comparison of Next Generation Peer-to-Peer Data Networks Erik Daniel and Florian Tschorsch Abstract—Decentralized, distributed storage offers a way to types of files [1]. Napster and Gnutella marked the beginning reduce the impact of data silos as often fostered by centralized and were followed by many other P2P networks focusing on cloud storage. While the intentions of this trend are not new, the specialized application areas or novel network structures. For topic gained traction due to technological advancements, most notably blockchain networks. As a consequence, we observe that example, Freenet [2] realizes anonymous storage and retrieval. a new generation of peer-to-peer data networks emerges. In this Chord [3], CAN [4], and Pastry [5] provide protocols to survey paper, we therefore provide a technical overview of the maintain a structured overlay network topology. In particular, next generation data networks. We use select data networks to BitTorrent [6] received a lot of attention from both users and introduce general concepts and to emphasize new developments. the research community. BitTorrent introduced an incentive Specifically, we provide a deeper outline of the Interplanetary File System and a general overview of Swarm, the Hypercore Pro- mechanism to achieve Pareto efficiency, trying to improve tocol, SAFE, Storj, and Arweave. We identify common building network utilization achieving a higher level of robustness. We blocks and provide a qualitative comparison. From the overview, consider networks such as Napster, Gnutella, Freenet, BitTor- we derive future challenges and research goals concerning data rent, and many more as first generation P2P data networks, networks. -
Privacy Enhancing Technologies 2003 an Analysis of Gnunet And
Privacy Enhancing Technologies 2003 An Analysis of GNUnet and the Implications for Anonymous, Censorship-Resistant Networks Dennis Kügler Federal Office for Information Security, Germany [email protected] 1 Anonymous, Censorship-Resistant Networks • Anonymous Peer-to-Peer Networks – Gnutella • Searching is relatively anonymous • Downloading is not anonymous • Censorship-Resistant Networks – Eternity Service • Distributed storage medium • Attack resistant • Anonymous, Censorship-Resistant Networks – Freenet – GNUnet 2 GNUnet: Obfuscated, Distributed Filesystem Content Hash Key: [H(B),H(E (B))] • H(B) – Content encryption: H(B) – Unambiguous filename: H(E (B)) H(B) • Content replication – Caching while delivering – Based on unambiguous filename • Searchability – Keywords 3 GNUnet: Peer-to-Peer MIX Network • Initiating node – Downloads content • Supplying nodes – Store content unencrypted • Intermediary nodes – Forward and cache encrypted content – Plausible deniability due to encryption • Economic model – Based on credit Query A Priority=20 B – Charge for queries c =c -20 B B - – Pay for responses 4 GNUnet Encoding • DBlocks DBlock DBlock ... DBlock – 1KB of the content – Content hash encrypted • IBlocks IBlock ... IBlock – CHKs of 25 DBlocks – Organized as tree – Content hash encrypted IBlock • RBlock – Description of the content – CHK of the root IBlock RBlock – Keyword encrypted 5 The Attacker Model • Attacker – Controls malicious nodes that behave correctly – Prepares dictionary of interesting keywords – Observes queries and -
Will Sci-Hub Kill the Open Access Citation Advantage and (At Least for Now) Save Toll Access Journals?
Will Sci-Hub Kill the Open Access Citation Advantage and (at least for now) Save Toll Access Journals? David W. Lewis October 2016 © 2016 David W. Lewis. This work is licensed under a Creative Commons Attribution 4.0 International license. Introduction It is a generally accepted fact that open access journal articles enjoy a citation advantage.1 This citation advantage results from the fact that open access journal articles are available to everyone in the word with an Internet collection. Thus, anyone with an interest in the work can find it and use it easily with no out-of-pocket cost. This use leads to citations. Articles in toll access journals on the other hand, are locked behind paywalls and are only available to those associated with institutions who can afford the subscription costs, or who are willing and able to purchase individual articles for $30 or more. There has always been some slippage in the toll access journal system because of informal sharing of articles. Authors will usually send copies of their work to those who ask and sometime post them on their websites even when this is not allowable under publisher’s agreements. Stevan Harnad and his colleagues proposed making this type of author sharing a standard semi-automated feature for closed articles in institutional repositories.2 The hashtag #ICanHazPDF can be used to broadcast a request for an article that an individual does not have access to.3 Increasingly, toll access articles are required by funder mandates to be made publically available, though usually after an embargo period. -
CS505: Distributed Systems
Cristina Nita-Rotaru CS505: Distributed Systems Lookup services. Chord. CAN. Pastry. Kademlia. Required Reading } I. Stoica, R. Morris, D. Karger, M. F. Kaashoek, H. Balakrishnan, Chord: A Scalable Peer-to-peer Lookup Service for Internet Applications, SIGCOMM 2001. } A Scalable Content-Addressable Network S.a Ratnasamy, P. Francis, M. Handley, R. Karp, S. Shenker, SIGCOMM 2001 } A. Rowstron and P. Druschel. "Pastry: Scalable, decentralized object location and routing for large-scale peer-to-peer systems". IFIP/ACM International Conference on Distributed Systems Platforms (Middleware), 2001 } Kademlia: A Peer-to-peer Information System Based on the XOR Metric. P. Maymounkov and D. Mazieres, IPTPS '02 2 DHTs 1: Lookup services Peer-to-Peer (P2P) Systems } Applications that take advantage of resources (storage, cycles, content, human presence) available at the edges of the Internet. } Characteristics: } System consists of clients connected through Internet and acting as peers } System is designed to work in the presence of variable connectivity } Nodes at the edges of the network have significant autonomy; no centralized control } Nodes are symmetric in function 4 DHTs Benefits of P2P and Applications } High capacity: all clients provide resources (bandwidth, storage space, and computing power). The capacity of the system increases as more nodes become part of the system. } Increased reliability: achieved by replicating data over multiple peers, and by enabling peers to find the data without relying on a centralized index server. } Applications: -
Piracy of Scientific Papers in Latin America: an Analysis of Sci-Hub Usage Data
Developing Latin America Piracy of scientific papers in Latin America: An analysis of Sci-Hub usage data Juan D. Machin-Mastromatteo Alejandro Uribe-Tirado Maria E. Romero-Ortiz This article was originally published as: Machin-Mastromatteo, J.D., Uribe-Tirado, A., and Romero-Ortiz, M. E. (2016). Piracy of scientific papers in Latin America: An analysis of Sci-Hub usage data. Information Development, 32(5), 1806–1814. http://dx.doi.org/10.1177/0266666916671080 Abstract Sci-Hub hosts pirated copies of 51 million scientific papers from commercial publishers. This article presents the site’s characteristics, it criticizes that it might be perceived as a de-facto component of the Open Access movement, it replicates an analysis published in Science using its available usage data, but limiting it to Latin America, and presents implications caused by this site for information professionals, universities and libraries. Keywords: Sci-Hub, piracy, open access, scientific articles, academic databases, serials crisis Scientific articles are vital for students, professors and researchers in universities, research centers and other knowledge institutions worldwide. When academic publishing started, academies, institutions and professional associations gathered articles, assessed their quality, collected them in journals, printed and distributed its copies; with the added difficulty of not having digital technologies. Producing journals became unsustainable for some professional societies, so commercial scientific publishers started appearing and assumed printing, sales and distribution on their behalf, while academics retained the intellectual tasks. Elsevier, among the first publishers, emerged to cover operations costs and profit from sales, now it is part of an industry that grew from the process of scientific communication; a 10 billion US dollar business (Murphy, 2016). -
Zeronet Presentation
ZeroNet Decentralized web platform using Bitcoin cryptography and BitTorrent network. ABOUT ZERONET Why? Current features We believe in open, free, and ◦ Real-time updated sites uncensored network and communication. ◦ Namecoin .bit domain support ◦ No hosting costs ◦ Multi-user sites Sites are served by visitors. ◦ Password less, Bitcoin's BIP32- ◦ Impossible to shut down based authorization It's nowhere because it's ◦ Built-in SQL server with P2P data everywhere. synchronization ◦ No single point of failure ◦ Tor network support Site remains online so long as at least 1 peer serving it. ◦ Works in any browser/OS ◦ Fast and works offline You can access the site even if your internet is unavailable. HOW DOES IT WORK? THE BASICS OF ASYMMETRIC CRYPTOGRAPHY When you create a new site you get two keys: Private key Public key 5JNiiGspzqt8sC8FM54FMr53U9XvLVh8Waz6YYDK69gG6hso9xu 16YsjZK9nweXyy3vNQQPKT8tfjCNjEX9JM ◦ Only you have it ◦ This is your site address ◦ Allows you to sign new content for ◦ Using this anyone can verify if the your site. file is created by the site owner. ◦ No central registry ◦ Every downloaded file is verified, It never leaves your computer. makes it safe from malicious code inserts or any modifications. ◦ Impossible to modify your site without it. MORE INFO ABOUT CRYPTOGRAPHY OF ZERONET ◦ ZeroNet uses the same elliptic curve based encryption as in your Bitcoin wallet. ◦ You can accept payments directly to your site address. ◦ Using the current fastest supercomputer, it would take around 1 billion years to "hack" a private key. WHAT HAPPENS WHEN YOU VISIT A ZERONET SITE? WHAT HAPPENS WHEN YOU VISIT A ZERONET SITE? (1/2) 1 Gathering visitors IP addresses: Please send some IP addresses for site 1EU1tbG9oC1A8jz2ouVwGZyQ5asrNsE4Vr OK, Here are some: 12.34.56.78:13433, 42.42.42.42:13411, .. -
CS 552 Peer 2 Peer Networking
CS 552 Peer 2 Peer Networking R. Martin Credit slides from B. Richardson, I. Stoica, M. Cuenca Peer to Peer • Outline • Overview • Systems: – Gnutella – Freenet – Chord – PlanetP Why Study P2P • Huge fraction of traffic on networks today – >=50%! • Exciting new applications • Next level of resource sharing – Vs. timesharing, client-server, P2P – E.g. Access 10’s-100’s of TB at low cost. P2P usage • CMU network (external to world), 2003 • 47% of all traffic was easily classifiable as P2P • 18% of traffic was HTTP • Other traffic: 35% – Believe ~28% is port- hopping P2P • Other sites have a similar distribution Big Picture • Gnutella – Focus is simple sharing – Using simple flooding • Bit torrent – Designed for high bandwidth • PlanetP – Focus on search and retrieval – Creates global index on each node via controlled, randomized flooding • Cord – Focus on building a distributed hash table (DHT) – Finger tables Other P2P systems • Freenet: – Focus privacy and anonymity – Builds internal routing tables • KaaZa • eDonkey • Napster – Success started the whole craze Key issues for P2P systems • Join/leave – How do nodes join/leave? Who is allowed? • Search and retrieval – How to find content? – How are metadata indexes built, stored, distributed? • Content Distribution – Where is content stored? How is it downloaded and retrieved? Search and Retrieval • Basic strategies: – Flooding the query – Flooding the index – Routing the query • Different tradeoffs depending on application – Robustness, scalability, legal issues Flooding the Query (Gnutella) N3 Lookup(“title”) N1 N2 N4 N5 Key=title N8 N6 Value=mp3 N7 Pros: highly robust. Cons: Huge network traffic Flooding the Index (PlanetP) Key1=title1 N3 N1 Key2=title2 N2 N4 N5 Lookup(“title4”) Key1=title3 N8 N6 Key2=title4 N7 Pros: Robust. -
Title: P2P Networks for Content Sharing
Title: P2P Networks for Content Sharing Authors: Choon Hoong Ding, Sarana Nutanong, and Rajkumar Buyya Grid Computing and Distributed Systems Laboratory, Department of Computer Science and Software Engineering, The University of Melbourne, Australia (chd, sarana, raj)@cs.mu.oz.au ABSTRACT Peer-to-peer (P2P) technologies have been widely used for content sharing, popularly called “file-swapping” networks. This chapter gives a broad overview of content sharing P2P technologies. It starts with the fundamental concept of P2P computing followed by the analysis of network topologies used in peer-to-peer systems. Next, three milestone peer-to-peer technologies: Napster, Gnutella, and Fasttrack are explored in details, and they are finally concluded with the comparison table in the last section. 1. INTRODUCTION Peer-to-peer (P2P) content sharing has been an astonishingly successful P2P application on the Internet. P2P has gained tremendous public attention from Napster, the system supporting music sharing on the Web. It is a new emerging, interesting research technology and a promising product base. Intel P2P working group gave the definition of P2P as "The sharing of computer resources and services by direct exchange between systems". This thus gives P2P systems two main key characteristics: • Scalability: there is no algorithmic, or technical limitation of the size of the system, e.g. the complexity of the system should be somewhat constant regardless of number of nodes in the system. • Reliability: The malfunction on any given node will not effect the whole system (or maybe even any other nodes). File sharing network like Gnutella is a good example of scalability and reliability. -
Escaping the Ossification Trap with Gnunet
Escaping the Ossification Trap with GNUnet Christian Grothoff BFH & The GNU Project 25.1.2018 \We shape our tools, and thereafter our tools shape us". {John Culkin What can be done? I Democracies are slow ) Effective regulation of mega-corporations exists only under dictatorships Dictatorship or Corpocracy? Regulation? I Charles Stross (@34c4) warns: Companies are AIs that develop faster than the law I Julia Reda (@IGF) warns: Regulation of platforms paradoxically can give them more power Regulation? I Charles Stross (@34c4) warns: Companies are AIs that develop faster than the law I Julia Reda (@IGF) warns: Regulation of platforms paradoxically can give them more power I Democracies are slow ) Effective regulation of mega-corporations exists only under dictatorships Dictatorship or Corpocracy? Better Technology! Data protection! Decentralization! Self-Organization! Technological impact assessment!1 1Difficult, but better than design-by-buzzword! Technological impact assessment case-study: Name systems DNS/DNSSEC DNS Server Root Zone a.root-servers.net. www.example.com? a.gtld-servers.net.test E2D3C9.... DNSSEC Trust Anchor NS . S4LXnQiBS... 49AAC1... DS RRSIG www.example.com? Recursive DNS Server Stub www.example.com? Name .com Resolver Server NS a.gtld-servers.net.test a.gtld-servers.net. A 93.184.216.119 DS 3490A6.... RRSIG example.com. K0rp9n... RRSIG com. U/ZW6P3c... AD www.example.com? RRSIG A 93.184.216.119 example.com. K0rp9n... DNS Server example.com a.iana-servers.net. RAINS Authority Server Root Zone 44 ) com ZK ; :registry www.example.com? -
1 Explain How Freenet Enables Individuals to Publish Anonymous Web Pages That Are Extremely Difficult to Censor. Does This Mean
Explain how FreeNet enables individuals to publish anonymous web pages that are extremely difficult to censor. Does this mean that the battle against state censorship in oppressive regimes has been won? Abstract Anonymity is a necessity for free speech, without it democracy cannot exist. Ensuring that anonymity has been hard to do online, however Freenet is a novel attempt to ensure anonymity. By encrypting and fragmenting documents which are stored on multiple nodes, and ensuring that nodes can only talk to a small subset, rather than a whole network, an individual’s anonymity becomes stronger. While Freenet does not make it impossible to trace what someone has downloaded, it does make it much harder. Freenet is a big step towards enabling people living in countries with oppressive governments to voice their views. Why is Anonymity important? The first amendment in the United States constitution is arguably one of the most important, and most controversial articles of law. It states that individuals have the right to free speech, free from persecution. Democracy is based on individuals electing representatives, based on their performance and what they say they will do. If freedom of speech is denied, then it is not possible for anyone to critique the government, and evaluate whether they are truly carrying out their responsibilities, or whether another party would be more appropriate. Indeed, without free speech, it is 1 impossible for other parties to exist, as their views will inevitably contradict that of the current government in power. Free speech can be ensured by anonymity. If an oppressive government does not know who is criticizing it, then it cannot punish the individual. -
Resource-Sharing Computer Communications Networks
PROCEEDISGS OF THE IEEE, VOL. 60, NO. 11, NOVEMBER 1972 1397 ington. D. C.: Spartan, 1970, pp. 569-579. [47] L. G. Roberts and B. Wessler, “The ARP.4 computer network de- [34] D. Klejtman,“Methods of investigatingconnectivity of large velopmentto achieve resource sharing, in Spring Joint Compztfer graphs, IEEE Trans.Circuit Theory (Corresp.),vol. CT-16, pp. Conf., AFIPS Conf. Proc., 1970, pp. 543-519. 232-233, May 1969. [48] --, “The ARPA computer network,” in Computer Communication [35] P. Krolak, IV. Felts,and G. Marble,“A man-machine approach Networks, F. Kuo and X. .‘\bramson, Eds.Iiew York: Prentice- towardsolving the traveling salesman problem,’! Commun.Ass. Hall, 1973, to be published. Comput. Mach., vol. 14, pp. 327-335, May 1971. [49] B. Rothfarb and M. Goldstein, ‘The one terminal Telpak problem,” [36] S. Lin,“Computer solutions of thetraveling salesman problem,” Oper. Res., vol. 19, pp. 156-169, Jan.-Feb. 1971. Bell Sysf. Tech. J., vol. 44, pp. 2245-2269, 1965. [SO] R. L. Sharma and M.T. El Bardai, “Suboptimal communications [37] T. Marilland L. G. Roberts, “Toward a cooperative netwotk of network synthesis,” in Proc. Int. Conf. Communications, vol. 7, pp. time-shared computers,” in Fall Joint Computer Conf.?AFIPS Conf. 19-11-19-16, 1970. Proc. Washington, D.C.: Spartan, 1966. ..[Sl] K. Steiglitz, P. Weiner, and D.J. Kleitman, “The design of minimum [38] B. Meister,H. R. Muller, and H. R.Rudin, “Sew optimization cost survivable networks,’! IEEE Trans. Circuit Theory, vol. CT-16, criteriafor message-switching networks,’ IEEE Trans.Commun. pp. 455-260, Nov. -
The Potential Harms of the Tor Anonymity Network Cluster Disproportionately in Free Countries
The potential harms of the Tor anonymity network cluster disproportionately in free countries Eric Jardinea,1,2, Andrew M. Lindnerb,1, and Gareth Owensonc,1 aDepartment of Political Science, Virginia Tech, Blacksburg, VA 24061; bDepartment of Sociology, Skidmore College, Saratoga Springs, NY 12866; and cCyber Espion Ltd, Portsmouth PO2 0TP, United Kingdom Edited by Douglas S. Massey, Princeton University, Princeton, NJ, and approved October 23, 2020 (received for review June 10, 2020) The Tor anonymity network allows users to protect their privacy However, substantial evidence has shown that the preponder- and circumvent censorship restrictions but also shields those ance of Onion/Hidden Services traffic connects to illicit sites (7). distributing child abuse content, selling or buying illicit drugs, or With this important caveat in mind, our data also show that the sharing malware online. Using data collected from Tor entry distribution of potentially harmful and beneficial uses is uneven, nodes, we provide an estimation of the proportion of Tor network clustering predominantly in politically free regimes. In particular, users that likely employ the network in putatively good or bad the average rate of likely malicious use of Tor in our data for ways. Overall, on an average country/day, ∼6.7% of Tor network countries coded by Freedom House as “not free” is just 4.8%. In users connect to Onion/Hidden Services that are disproportion- countries coded as “free,” the percentage of users visiting Onion/ ately used for illicit purposes. We also show that the likely balance Hidden Services as a proportion of total daily Tor use is nearly of beneficial and malicious use of Tor is unevenly spread globally twice as much or ∼7.8%.