Utreexo: A dynamic hash-based accumulator optimized for the Bitcoin UTXO set
It wasn't me! Repudiability and (Un)claimability of Ring Signatures
by Thaddeus Dryja (MIT’s Digital Currency Initiative)
Abstract: In the Bitcoin consensus network, all nodes come to agreement on the set of Unspent Transaction Outputs (The “UTXO” set). The size of this shared state is a scalability constraint for the network, as the size of the set expands as more users join the system, increasing resource requirements of all nodes. Decoupling the network’s state size from the storage requirements of individual machines would reduce hardware requirements of validating nodes. We introduce a hash based accumulator to locally represent the UTXO set, which is logarithmic in the size of the full set. Nodes attach and propagate inclusion proofs to the inputs of transactions, which along with the accumulator state, give all the information needed to validate a transaction. While the size of the inclusion proofs results in an increase in network traffic, these proofs can be discarded after verification, and aggregation methods can reduce their size to a manageable level of overhead. In our simulations of downloading Bitcoin’s blockchain up to early 2019 with 500MB of RAM allocated for caching, the proofs only add approximately 25% to the amount otherwise downloaded.
DCI's Neha Narula Interviewed by Anderson Cooper on '60 Minutes' - 'Bitcoin's Wild Ride'
by Sunoo Park (MIT Media Lab) and Adam Sealfon (MIT CSAIL)
To appear in the International Cryptology Conference (CRYPTO 2019).
Podcast: DCI's Neha Narula interviewed by Hari Sreenivasan for CNN's Amanpour
“Ten years ago, a mysterious computer programmer invented a new type of money that wasn't backed by any government or kept in any bank. There were no coins or bills, just long strings of letters and numbers stored inside a network of computers that anybody could be a part of by downloading some free software over the Internet. Today that computerized currency, bitcoin, is well-known, though little understood, and bitcoin's popularity has inspired the creation of thousands of other types of digital money, known as "cryptocurrency." Over the last decade, you could have made a five million percent profit by investing in cryptocurrency. Or you could have lost everything. It has been a wild ride, and few people have experienced the highs and lows…” Cooper. A (2019, May 19) Bitcoin’s Wild Ride.
DCI's Tadge Dryja interviewed by WHAT BITCOIN DID for a podcast on 'The Limitations of Lightning'
“Republican Senator Mitt Romney and Democratic Senator Chris Murphy join Christiane Amanpour from Washington D.C. to discuss their bipartisan trip to the Middle East and the growing tensions between the U.S. and Iran. Bill Weld, the only Republican challenging President Trump in the 2020 election talks about why he decided to run. Our Hari Sreenivasan talks to Neha Narula, the Director of the Digital Currency Initiative at the MIT Media Lab, about the future of cryptocurrencies.” Amanpour Podcast
DCI's Madars Virza presents: zk-SHARKs: Combining Succinct Verification and Public Coin Setup at ZKPROOF Workshop
In this episode for Lightning Month, I talk with Tadge Dryja, the co-author of the Lightning Network whitepaper. We discuss the limitations of the lightning network, why Bitcoin might not be for everyone, alternative scaling ideas, fees and inflation.
Cryptanalysis of Curl-P and Other Attacks on the IOTA Cryptocurrency
‘zk-SHARKs: Combining Succinct Verification and Public Coin Setup’ by Madars Virza (MIT DCI)
Madars presents at ZKPROOF Workshop on his project zk-SHARKS.
DCI Mentioned in BBC's 'Should Google, Amazon and Facebook fear this woman?'
By Ethan Heilman (Boston Uni), Neha Narula (MIT Media Lab), Garrett Tanzer (Harvard), James Lovejoy (MIT Media Lab), Michael Colavita (Harvard), Madars Virza (MIT Media Lab), and Tadge Dryja (MIT Media Lab)
We present attacks on the cryptography formerly used in the IOTA blockchain, including under certain conditions the ability to forge signatures. We developed practical attacks on IOTA’s cryptographic hash function Curl-P-27, allowing us to quickly generate short colliding messages. These collisions work even for messages of the same length. Exploiting these weaknesses in Curl-P-27, we broke the EU-CMA security of the former IOTA Signature Scheme (ISS). Finally, we show that in a chosen-message setting we could forge signatures and multi-signatures of valid spending transactions (called bundles in IOTA).
MIT Technology Review and MIT Media Lab Digital Currency Initiative Announce 2019 Business of Blockchain Conference on May 2
US presidential hopeful Elizabeth Warren says she'd consider dismantling the tech giants should she ever get the top job. But is this really necessary or even possible?
Read full article here
DCI's Director interviewed for Fortune's latest article: 'Zcash Discloses Vulnerability That Could Have Allowed 'Infinite Counterfeit' Cryptocurrency'
Today, MIT Technology Review announced the third annual Business of Blockchain event, which will take place on May 2, 2019 at the MIT Media Lab. The event is held in collaboration with the Digital Currency Initiative, an MIT Media Lab research group focusing on cryptocurrencies and their underlying technology, and brings together industry leaders and pioneers in this emerging field to examine the technology, ethics, and impact of blockchains.
Read the Article here
"DCI Working Groups: the blockchain sandbox at MIT" On Medium by DCI's Alin Dragos
On March 1 of last year, Ariel Gabizon was tidying up a presentation he was preparing to deliver the following day at a financial cryptography conference on the Caribbean island of Curaçao when he spotted a seemingly small mathematical mistake that could, he realized, jeopardize billions of dollars in capital.
Read the full article here
Coin Rivet's 'Single Lightning Network node routes record number of Satoshis in a day'
Our MIT motto, mens et manus, is a call-to-action to be more than mere technologists and to learn (by doing!) how to be thoughtful makers of a better world. The Digital Currency Initiative (DCI) Working Group Program creates a sandbox for interdisciplinary teams of students to hack on pressing topics in cryptocurrency and blockchain technology. Students from the Blockchain Lab will collaborate with instructors, companies and DCI to investigate uses of blockchain technology and how to integrate it into viable business models.
Read the full post on Medium
Coindesk's 'This Scaling Tech Could Let You Sync Bitcoin Straight From Your Phone' using UTreeXO created by Tadge Dryja
A Lightning Network node hosted by Satoshi Labs successfully routed one Bitcoin worth of Lightning transactions in a 24-hour period
Read the full article and watch the video here
Coindesk's 'Bitcoin at 10[years old]': From Fearing Bitcoin To Fixing Its Worst Problem: Tadge Dryja
“Maybe we don’t have to store everything ourselves.”
That’s Tadge Dryja, cryptocurrency research scientist at the MIT Digital Currency Initiative, explaining the concept behind his bitcoin scaling solution, “utreexo.”
Based on an idea that has been pursued by developers for many years, utreexo seeks to streamline an aspect of bitcoin’s code that leads to heavy storage requirements over time.
Read the original article here
WGBH News: More local ATMs Will Soon Dispense 'Cryptocurrencies' - Arun Rath Interviews DCI's Director Neha Narula and Others
A celebration of 10 years of Bitcoin features DCI's Tadge Dryja story:
““I thought I would go to jail.”
That’s why Tadge Dryja, one of two principal researchers who would go on to envision lightning – what has become arguably the most important innovation in the quest to bring bitcoin to the masses – kept his passion for the technology to himself when he first heard about it in 2011.”
Read the article on Coindesk here
DCI Director interviewed for The Wall Street Journal: "Winklevosses’ Cryptocurrency Exchange Says the ‘Revolution Needs Rules’" By Nat Ives
DCI’s Director Neha Narula was interviewed by WGBH on the topic of how making cryptocurrency mainstream is beneficial to the general public, by using more tangible methods.
Read the article or listen to the post here
Introducing DCI's New Podcast: Grey Mirror
DCI’s Director Neha Narula commented on ‘Gemini Trust ad campaign calling for new regulations’ in an article for The Wall Street Journal
Cryptocurrency Research Review
In this episode: Tadge Dryja, a research scientist at DCI who co-invented the Lightning Network. We chat about his current research (uTreeXO, a dynamic accumulator for Bitcoin state) and discuss non-fork ways to bootstrap upgrades to a network (a bridge node for uTreeXO).
Michael Casey's "Vertcoin’s Struggle Is Real: Why the Latest Crypto 51% Attack Matters"
Introducing the first issue of the DCI’s Cryptocurrency Research Review. Read it here
You may not have heard of Vertcoin, a crypto project designed to curtail concentration in mining power in the interests of broad-based participation. But if you care about security, decentralization and open access for cryptocurrencies, then the questions raised by a recent breach of its blockchain will matter to you.