Showing posts with label Stanford. Show all posts
Showing posts with label Stanford. Show all posts

November 20, 2017

Stanford’s Applied Cryptography Group aims to Bulletproof Bitcoin

By C. Edward Kelso - November 20, 2017 (news.bitcoin.com)


Stanford University’s Applied Cryptography Group (ACG) is proposing Bulletproofs, a way to drastically reduce blockchain data, roughly ten-fold. The ACG team argues how using aggregation for transaction proofs and reducing block size will result in two goals long sought in Bitcoin, confidentiality and speed. 

Bitcoin’s Bulletproofs


Bulletproofs: Efficient Range Proofs for Confidential Transactions is a working publication from Stanford University’s Applied Cryptography Group. The project is overseen by professor Dan Boneh, and it involves PhD students and researchers from Stanford, University College London, and Blockstream. “Bulletproofs are designed to enable efficient confidential transactions in Bitcoin and other cryptocurrencies,” a background abstract begins.

A common misconception is transacting in bitcoin is somehow anonymous, confidential. The press often touts it as such, especially in the service of crime.


The irony of payment systems in the digital age is how public they are. Entire industries have been built up around gathering payment information, habits. Bitcoin is a step, for sure, toward thwarting institutional electronic payments’ invasiveness, but it is a long way from the anonymity of cash, for example.

“Confidential transactions hide the amount that is transferred in the transaction,” the paper continues, “Every confidential transaction contains a cryptographic proof that the transaction is valid. Bulletproofs shrink the size of the cryptographic proof from over 10kB to less than 1kB,” they claim.

Could Bulletproofs Ease the Scaling Debate?


Nothing in the paper overtly refers to the ongoing scaling debate, other than Bulletproofs assisting in scaling as a general idea. Those championing large block sizes have done so under the criticism of slow transaction times and higher fees. Meanwhile, status-quo arguments revolve around a bitcoin not reserved for micropayments, more for a settlement standard and store of value.

“If all Bitcoin transactions were confidential and used Bulletproofs, then the total size of the blockchain would be only 17 GB, compared to 160 GB with the currently used proofs,” authors Benedikt Bünz, Jonathan Bootle, Dan Boneh, Andrew Poelstra, Pieter Wiulle, Greg Maxwell insist.

Professor Dan Boneh
zkSNARKs, popularized in ZCash, are precursors to Bulletproofs. However, “Bulletproofs are short non-interactive zero-knowledge proofs that require no trusted setup,” which is the case with SNARKs.

“A Bulletproof can be used to convince a verifier that an encrypted plaintext is well formed. For example, prove that an encrypted number is in a given range, without revealing anything else about the number,” the ACG team asserts. The tradeoff in using Bulletproofs is in verification, as it is “more time consuming than verifying a SNARK proof.”

Block efficiency usage means the ACG proposal can “have many other applications in cryptographic protocols,” they write, “such as shortening proofs of solvency, short verifiable shuffles, confidential smart contracts, and as a general drop-in replacement for Sigma-protocols.”


Images courtesy of: Pixabay, Remington, Twitter. 


C. Edward Kelso

C. Edward Kelso is a long-time fintech journalist, passionately covering the cryptocurrency space since 2014.

October 13, 2017

Scaling Bitcoin announces this year’s program and a new developer bootcamp

By Aaron van Wirdum, Staff Writer - October 13, 2017 (bitcoinmagazine.com)

Today, Scaling Bitcoin, the international engineering conference focused on Bitcoin and blockchain research, released its program for the 2017 edition. The conference, to be held in Stanford, California, in the first weekend of November, will also introduce a new side event this year: Bitcoin Edge, a bootcamp for starting Bitcoin developers.


“The program is extremely interesting because it delivers cutting edge research on different blockchain scalability approaches, fungibility, consensus, data propagation, alternative techniques for handling blockchains and many other topics,” said Anton Yemelyanov, chair of the Scaling Bitcoin Planning Committee.

Scaling Bitcoin Stanford

After events in Montreal, Hong Kong and Milan, the fourth edition of the Scaling Bitcoin conference is taking place at Stanford University on November 4 and 5 of this year.

Where the first two editions of Scaling Bitcoin were mainly focused on scaling and scalability, the third edition broadened the scope of the conference to include a more diverse set of topics. This trend will continue in Stanford, where talks will range from highly technical topics concerning privacy and fungibility, to fee markets and fee estimation, censorship resistance and more.

“Bitcoin is the origin of all distributed ledger technology,” said Yemelyanov. “Scaling Bitcoin has been fortunate to act as a vehicle for bringing the audience technologies such as Segregated Witness and MimbleWimble, all of which have been adopted or incorporated into various blockchain projects. We hope that other material presented by our participants will be of similar value and help the industry advance the research and development of blockchains.”

Yemelyanov added that another key goal for Scaling Bitcoin conferences is to bring engineers and other technical minds together in a physical space where they can discuss their work in person.

“It is through collaboration where a lot of ideas are born and have potential of becoming reality,” he said.

Bitcoin Edge Dev++

In addition to the conference itself, Scaling Bitcoin is also introducing a two-day technical bootcamp for experienced developers getting into Bitcoin: Bitcoin Edge.

This nonprofit initiative is an effort to help scale the development capacity of the industry, Yemelyanov explained:

“One of the approaches of helping the industry scale is to scale the much needed development capacity of the industry. There is a clear talent deficit and we are trying to help all industry participants by running a nonprofit workshop that will allow developers to gain complete understanding of primitives that comprise Bitcoin and blockchains in general and be able to start working in this field.”

Bitcoin Edge will be led by well-known Bitcoin developers and academics Anditto Heristyo, Ethan Heilman, John Newbery, Karl-Johan Alm, Nicolas Dorier, Thaddeus Dryja and Jimmy Song. They’ll introduce participants to a range of technical Bitcoin-related topics, including Elliptic Curve cryptography, transaction structures, difficulty calculation and adjustments, and much more.

This workshop will take place on the November 2 and 3. For more information on the Bitcoin Edge initiative, visit bitcoinedge.org.

See here for the full Scaling Bitcoin Stanford program.