1. bookVolume 2022 (2022): Edizione 1 (January 2022)
Dettagli della rivista
Prima pubblicazione
16 Apr 2015
Frequenza di pubblicazione
4 volte all'anno
access type Accesso libero

Toward Uncensorable, Anonymous and Private Access Over Satoshi Blockchains

Pubblicato online: 20 Nov 2021
Volume & Edizione: Volume 2022 (2022) - Edizione 1 (January 2022)
Pagine: 207 - 226
Ricevuto: 31 May 2021
Accettato: 16 Sep 2021
Dettagli della rivista
Prima pubblicazione
16 Apr 2015
Frequenza di pubblicazione
4 volte all'anno

Providing unrestricted access to sensitive content such as news and software is difficult in the presence of adaptive and resourceful surveillance and censoring adversaries. In this paper we leverage the distributed and resilient nature of commercial Satoshi blockchains to develop the first provably secure, censorship resistant, cost-efficient storage system with anonymous and private access, built on top of commercial cryptocurrency transactions. We introduce max-rate transactions, a practical construct to persist data of arbitrary size entirely in a Satoshi blockchain. We leverage max-rate transactions to develop UWeb, a blockchain-based storage system that charges publishers to self-sustain its decentralized infrastructure. UWeb organizes blockchain-stored content for easy retrieval, and enables clients to store and access content with provable anonymity, privacy and censorship resistance properties.

We present results from UWeb experiments with writing 268.21 MB of data into the live Litecoin blockchain, including 4.5 months of live-feed BBC articles, and 41 censorship resistant tools. The max-rate writing throughput (183 KB/s) and blockchain utilization (88%) exceed those of state-of-the-art solutions by 2-3 orders of magnitude and broke Litecoin’s record of the daily average block size. Our simulations with up to 3,000 concurrent UWeb writers confirm that UWeb does not impact the confirmation delays of financial transactions.


[1] Margot Williams, Henrik Moltke, Micah Lee, and Ryan Gallagher. Meltdown Showed Extent of NSA Surveillance. The Intercept, https://theintercept.com/2019/05/29/nsasidtoday-surveillance-intelligence/, 2019. Search in Google Scholar

[2] Government Monitoring of Social Media: Legal and Policy Challenges. https://www.brennancenter.org/our-work/research-reports/government-monitoring-social-media-legal-and-policy-challenges. Search in Google Scholar

[3] The List of Blocked Websites in China. https://www.saporedicina.com/english/list-of-blocked-websites-in-china/. Search in Google Scholar

[4] List of Websites Blocked in Russia. https://en.wikipedia.org/wiki/List_of_websites_blocked_in_Russia. Search in Google Scholar

[5] Devin Coldewey. China moves to ban foreign software and hardware from state offices. TechCrunch, https://techcrunch.com/2019/12/09/china-moves-to-ban-foreign-software-and-hardware-from-state-offices/, December 2019. Search in Google Scholar

[6] U.S. bans WeChat, TikTok as China becomes major focus of election. The Washington Post, https://www.washingtonpost.com/technology/2020/09/18/tiktokwechat-ban-trump/, September 2020. Search in Google Scholar

[7] Stephanie Kirchgaessner, Emma Graham-Harrison, and Lily Kuo. China clamping down on coronavirus research, deleted pages suggest. The Guardian, https://www.theguardian.com/world/2020/apr/11/china-clamping-down-on-coronavirus-research-deleted-pages-suggest, 2020. Search in Google Scholar

[8] George Cooper. Chinese state censorship of COVID-19 research represents a looming crisis for academic publishers. https://blogs.lse.ac.uk/impactofsocialsciences/2020/04/24/chinese-state-censorship-of-covid-19-research-represents-a-looming-crisis-for-academic-publishers/, 2020. Search in Google Scholar

[9] Does your VPN Keep Logs? 120 VPN Logging Policies Revealed. https://www.comparitech.com/vpn/vpn-logging-policies/. Search in Google Scholar

[10] Hundreds of Millions Have Downloaded Suspicious VPN Apps With Serious Privacy Flaws. Apple and Google Haven’t Taken Action. Entrepreneur, https://www.entrepreneur.com/article/337885. Search in Google Scholar

[11] Study finds half of most popular VPN apps linked to China. FinancialTimes,https://www.ft.com/content/e5567d8aee65-11e8-89c8-d36339d835c0. Search in Google Scholar

[12] Jiang Peng seized and warned for watching YouToube videos and shopping on Amazon. Turbo VPN records used as evidence. https://twitter.com/SpeechFreedomCN/status/1211095986908516352. Search in Google Scholar

[13] Tor 0day: Finding IP Addresses. https://www.hackerfactor.com/blog/index.php?/archives/896-Tor-0day-Finding-IP-Addresses.html. Search in Google Scholar

[14] IBM Blockchain. Now delivering value around the world. https://www.ibm.com/blockchain. Search in Google Scholar

[15] AWS Blockchain Partners: Accelerating your distributed ledger journey. Amazon, https://aws.amazon.com/partners/blockchain/. Search in Google Scholar

[16] Microsoft Azure Blockchain. Develop, test, and deploy secure blockchain apps. https://azure.microsoft.com/enus/solutions/blockchain/. Search in Google Scholar

[17] MaidSafe. https://maidsafe.net/. Search in Google Scholar

[18] FileCoin. https://filecoin.io/. Search in Google Scholar

[19] Sia: Fully Decentralized Cloud. https://sia.tech/. Search in Google Scholar

[20] LTI: Let’s Solve. https://www.lntinfotech.com/services/consulting/blockchain/. Search in Google Scholar

[21] Eleftherios Kokoris-Kogias, Enis Ceyhun Alp, Sandra Deepthy Siby, Nicolas Gailly, Philipp Jovanovic, Linus Gasser, and Bryan Ford. Hidden in plain sight: Storing and managing secrets on a public ledger. IACR Cryptology ePrint Archive, 2018. Search in Google Scholar

[22] Alevtina Dubovitskaya, Zhigang Xu, Samuel Ryu, Michael Schumacher, and Fusheng Wang. Secure and trustable electronic medical records sharing using blockchain. CoRR, abs/1709.06528, 2017. Search in Google Scholar

[23] Muneeb Ali, Jude Nelson, Ryan Shea, and Michael J. Freedman. Blockstack: A Global Naming and Storage System Secured by Blockchains. In Proceedings of the Usenix Annual Technical Conference, pages 181–194, 2016. Search in Google Scholar

[24] Muneeb Ali, Ryan Shea, Jude Nelson, and Michael J Freedman. Blockstack: A new decentralized internet. Whitepaper, 2017. Search in Google Scholar

[25] Alin Tomescu and Srinivas Devadas. Catena: Efficient Nonequivocation via Bitcoin. In Proceedings of IEEE Symposium on Security and Privacy, pages 393–409, 2017.10.1109/SP.2017.19 Search in Google Scholar

[26] Xueping Liang, Sachin Shetty, Deepak Tosh, Charles Kamhoua, Kevin Kwiat, and Laurent Njilla. Provchain: A blockchain-based data provenance architecture in cloud environment with enhanced privacy and availability. In Proceedings of the 17th IEEE/ACM International Symposium on Cluster, Cloud and Grid Computing, pages 468–477, 2017.10.1109/CCGRID.2017.8 Search in Google Scholar

[27] Bin Liu, Xiao Liang Yu, Shiping Chen, Xiwei Xu, and Liming Zhu. Blockchain based data integrity service framework for iot data. In Web Services (ICWS), 2017 IEEE International Conference on, pages 468–475. IEEE, 2017.10.1109/ICWS.2017.54 Search in Google Scholar

[28] Hossein Shafagh, Lukas Burkhalter, Anwar Hithnawi, and Simon Duquennoy. Towards blockchain-based auditable storage and sharing of iot data. In Proceedings of the 2017 on Cloud Computing Security Workshop, pages 45–50, 2017.10.1145/3140649.3140656 Search in Google Scholar

[29] Antorweep Chakravorty and Chunming Rong. Ushare: User controlled social media based on blockchain. In Proceedings of the 11th International Conference on Ubiquitous Information Management and Communication, pages 99:1–99:6, 2017. Search in Google Scholar

[30] Adiseshu Hari and T. V. Lakshman. The Internet Blockchain: A Distributed, Tamper-Resistant Transaction Framework for the Internet. In Proceedings of the 15th ACM Workshop on Hot Topics in Networks, pages 204–210, 2016.10.1145/3005745.3005771 Search in Google Scholar

[31] Binanda Sengupta, Samiran Bag, Sushmita Ruj, and Kouichi Sakurai. Retricoin: Bitcoin based on compact proofs of retrievability. In Proceedings of the 17th International Conference on Distributed Computing and Networking, 2016.10.1145/2833312.2833317 Search in Google Scholar

[32] Matthias Wachs, Martin Schanzenbach, and Christian Grothoff. A censorship-resistant, privacy-enhancing and fully decentralized name system. In International Conference on Cryptology and Network Security, pages 127–142. Springer, 2014.10.1007/978-3-319-12280-9_9 Search in Google Scholar

[33] Andrew Miller, Ari Juels, Elaine Shi, Bryan Parno, and Jonathan Katz. Permacoin: Repurposing bitcoin work for data preservation. In IEEE Symposium on Security and Privacy (SP), pages 475–490, 2014.10.1109/SP.2014.37 Search in Google Scholar

[34] Nir Kshetri. Chinese internet users turn to the blockchain to fight against government censorship. The Conversation, https://theconversation.com/chinese-internet-users-turn-to-the-blockchain-to-fight-against-government-censorship-111795, 2019. Search in Google Scholar

[35] Wolfie Zhao. Pharma Scandal Prompts Calls to Put Vaccine Data on a Blockchain. CoinDesk, https://www.coindesk.com/pharma-scandal-prompts-calls-to-put-vaccine-data-ona-blockchain, 2018. Search in Google Scholar

[36] Ruben Recabarren and Bogdan Carbunar. Tithonus: A Bit-coin Based Censorship Resilient System. PoPETS, 2019(1), 2019.10.2478/popets-2019-0005 Search in Google Scholar

[37] Mohsen Minaei, Pedro Moreno-Sanchez, and Aniket Kate. Moneymorph: Censorship resistant rendezvous using permissionless cryptocurrencies. Proceedings on Privacy Enhancing Technologies, 2020(3):404–424, 2020. Search in Google Scholar

[38] CoinMarketCap. https://coinmarketcap.com/. Search in Google Scholar

[39] Total Number of (Bitcoin) Transactions. https://www.blockchain.com/charts/n-transactions-total. Search in Google Scholar

[40] Total Number of (Litecoin) Transactions. https://blockchair.com/litecoin. Search in Google Scholar

[41] Transaction malleability. https://en.bitcoin.it/wiki/Transaction_malleability. Search in Google Scholar

[42] Miner Fees - Historic rules for fee transactions. https://en.bitcoin.it/wiki/Miner_fees#Historic_rules_for_free_transactions. Search in Google Scholar

[43] Miner Fees - Relaying. https://en.bitcoin.it/wiki/Miner_fees#Relaying. Search in Google Scholar

[44] Len Sassman tribute by Dan Kaminsky. http://www.slideshare.net/dakami/black-ops-of-tcpip-2011-black-hatusa-2011. Search in Google Scholar

[45] Apertus 0.3.17-beta. Archive data on your favorite blockchains. http://apertus.io/. Search in Google Scholar

[46] Number of OP_RET operations check. https://github.com/bitcoin/bitcoin/blob/0.18/src/policy/policy.cpp#L135. Search in Google Scholar

[47] Ruben Recabarren and Bogdan Carbunar. Tithonus: A bit-coin based censorship resilient system. PoPETs, 2019(1):68–86, 2019. Search in Google Scholar

[48] Peter Todd. Input Writing Example. https://github.com/petertodd/python-bitcoinlib/blob/master/examples/publish-text.py. Search in Google Scholar

[49] Majority Attack. https://en.bitcoin.it/wiki/Majority_attack. Search in Google Scholar

[50] Largest Crypto-Mining Marketplace. https://www.nicehash.com/. Search in Google Scholar

[51] ISP Tracking – 4 Ways to Stop it and Protect Your Privacy. https://digital.com/blog/isp-tracking/. Search in Google Scholar

[52] Is My Internet Service Provider Spying on Me? https://securethoughts.com/internet-service-provider-spying/. Search in Google Scholar

[53] IsStandard() Function. https://github.com/bitcoin/bitcoin/blob/0.18/src/policy/policy.cpp#L57. Search in Google Scholar

[54] Maximum Transaction Size. https://github.com/bitcoin/bitcoin/blob/0.16/src/policy/policy.h#L24. Search in Google Scholar

[55] Effective ScriptSig Size. https://github.com/bitcoin/bitcoin/blob/0.16/src/policy/policy.cpp#L108. Search in Google Scholar

[56] Standard Transaction. https://bitcoin.org/en/glossary/standard-transaction. Search in Google Scholar

[57] Unconfirmed chains. https://github.com/bitcoin/bitcoin/blob/57b34599b2deb179ff1bd97ffeab91ec9f904d85/doc/release-notes/release-notes-0.12.0.md. Search in Google Scholar

[58] John Holowczak and Amir Houmansadr. Cachebrowser: Bypassing chinese censorship without proxies using cached content. In Proceedings of the 22nd ACM SIGSAC Conference on Computer and Communications Security, pages 70–83. ACM, 2015.10.1145/2810103.2813696 Search in Google Scholar

[59] David Fifield, Chang Lan, Rod Hynes, Percy Wegmann, and Vern Paxson. Blocking-resistant communication through domain fronting. Proceedings on Privacy Enhancing Technologies, 2015(2):46–64, 2015.10.1515/popets-2015-0009 Search in Google Scholar

[60] Bitcoin Adoption in the world. https://blog.chainalysis.com/reports/2020-global-cryptocurrency-adoption-index-2020. Search in Google Scholar

[61] Bitcoin trading volume. https://www.statista.com/statistics/1195753/bitcoin-trading-selected-countries/. Search in Google Scholar

[62] Andrew Sward, Vecna OP, and Forrest Stonedahl. Data Insertion in Bitcoin’s Blockchain. Augustana Digital Commons, 2017.10.5195/ledger.2018.101 Search in Google Scholar

[63] Natkamon Tovanich, Nicolas Soulié, and Petra Isenberg. Visual analytics of bitcoin mining pool evolution: on the road toward stability? In 3rd International Workshop on Blockchains and Smart Contracts (BSC 2020-2021), held in conjunction with the 11th IFIP International Conference on New Technologies, Mobility and Security (IFIP NTMS 2021), 2021.10.1109/NTMS49979.2021.9432675 Search in Google Scholar

[64] Bitcoin Wiki. Variable length integer format. https://en.bitcoin.it/wiki/Protocol_documentation#Variable_length_integer. Search in Google Scholar

[65] Mendel Rosenblum and John K. Ousterhout. The design and implementation of a log-structured file system. ACM Trans. Comput. Syst., 10(1):26–52, February 1992.10.1145/146941.146943 Search in Google Scholar

[66] John H. Hartman and John K. Ousterhout. The zebra striped network file system. ACM Trans. Comput. Syst., 13(3):274–310, August 1995.10.1145/210126.210131 Search in Google Scholar

[67] Athicha Muthitacharoen, Robert Morris, Thomer M. Gil, and Benjie Chen. Ivy: A read/write peer-to-peer file system. SIGOPS Oper. Syst. Rev., 36(SI):31–44, December 2002.10.1145/844128.844132 Search in Google Scholar

[68] Litecoin - Download. https://litecoin.org/. Search in Google Scholar

[69] Saias” “Evyatar. BITCOINS, BLOCKCHAINS, AND BOT-NETS. https://blogs.akamai.com/sitr/2021/02/bitcoinsblockchains-and-botnets.html. Search in Google Scholar

[70] Dominic Deuber, Bernardo Magri, and Sri Aravinda Krishnan Thyagarajan. Redactable blockchain in the permissionless setting. CoRR, abs/1901.03206, 2019. Search in Google Scholar

[71] Eugenia Politou, Fran Casino, Efthimios Alepis, and Constantinos Patsakis. Blockchain mutability: Challenges and proposed solutions. arXiv preprint arXiv:1907.07099, 2019. Search in Google Scholar

[72] Martin Florian, Sebastian Henningsen, Sophie Beaucamp, and Björn Scheuermann. Erasing data from blockchain nodes. In 2019 IEEE European Symposium on Security and Privacy Workshops (EuroS&PW), pages 367–376. IEEE, 2019.10.1109/EuroSPW.2019.00047 Search in Google Scholar

[73] David Derler, Kai Samelin, Daniel Slamanig, and Christoph Striecks. Fine-grained and controlled rewriting in blockchains: Chameleon-hashing gone attribute-based. IACR Cryptology ePrint Archive, 2019:406, 2019. Search in Google Scholar

[74] Tracy M. Cook. How much U.S. newspapers charge for digital subscriptions. https://www.americanpressinstitute.org/publications/reports/digital-subscription-pricing/. Search in Google Scholar

[75] Curated list of open-source anti-censorship tools. https://github.com/danoctavian/awesome-anti-censorship. Search in Google Scholar

[76] Alternative methods to download Tor Browser. https://www.torproject.org/projects/gettor. Search in Google Scholar

[77] Stegotorus. https://sri-csl.github.io/stegotorus/. Search in Google Scholar

[78] UProxy-client. https://sourceforge.net/projects/unr-proxy/files/UProxy-Client/. Search in Google Scholar

[79] BitSmuggler. https://github.com/danoctavian/bit-smuggler. Search in Google Scholar

[80] Miner Fees: Including in Blocks. https://en.bitcoin.it/wiki/Miner_fees#Including_in_Blocks. Search in Google Scholar

[81] Litecoin Block Size Historical Chart. https://bitinfocharts. com/comparison/size-ltc.html. Search in Google Scholar

[82] Download Tor. https://www.torproject.org/download/download. Search in Google Scholar

[83] Gregory Rocco. Public Blockchains as a Means to Resist Information Censorship. CUNY Academic Works, https://academicworks.cuny.edu/gc_etds/2995, 2019. Search in Google Scholar

[84] 2020 World Press Freedom Index. https://rsf.org/en/ranking. Search in Google Scholar

[85] Global Bitcoin Nodes Distribution. https://bitnodes.io/. Search in Google Scholar

[86] Total Bitcoin Hashrate. https://www.blockchain.com/charts/hash-rate. Search in Google Scholar

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