UCL Crypto Currencies And Bitcoin Seminarnicolascourtois.com/bitcoin/paycoin_seminar_0.pdfCrypto...

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UCL Crypto Currencies And Bitcoin Seminar And Bitcoin Seminar Nicolas T. Courtois - University College London, UK

Transcript of UCL Crypto Currencies And Bitcoin Seminarnicolascourtois.com/bitcoin/paycoin_seminar_0.pdfCrypto...

Page 1: UCL Crypto Currencies And Bitcoin Seminarnicolascourtois.com/bitcoin/paycoin_seminar_0.pdfCrypto Currencies UCL Bitcoin Seminar UCL crypto currency seminar and special interest group

UCLCrypto Currencies

And Bitcoin SeminarAnd Bitcoin Seminar

Nicolas T. Courtois

- University College London, UK

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Crypto Currencies

UCL Bitcoin SeminarUCL crypto currency seminar and special interest group

every Thur 12h00-14h00 -room and exact hour varies

Public web page: www.want2pay.com

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Blog: blog.bettercrypto.com

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This Seminar

This is a university research seminar. With talks, demos, discussions, etc.Our goals are:• Learn non-trivial facts about bitcoin, highly technical maths and crypto.• Discover many “facts” we have been told about bitcoin are… NOT true.

– break bitcoin: will require serious effort.

• Improve bitcoin - so that it would be resistant to cybercriminals / NSA.

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– write our own software and apps, looking for developers

• Develop methods to investigate what is going on in these networks: – for example undoing the anonymity, discovering statistically significant patterns, etc.

• Produce scientific works and Master/PhD theses about bitcoin.

The seminar will run every week at UCL. Slides and other materials will be made available on a selective basis.

I will also invite external people as speakers and stake holders.

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Donations Policy

Address for donations: 1Mx9TMAfhrJ9DfETMLmF5ytkGitqwYPTQN

Donations will be spent on:• Drinks and food for participants

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• Drinks and food for participants of UCL bitcoin seminar

• Student stipends• Research expenses

Thanks for generous donations already received!

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Speakers Wanted!

Speakers are wanted, also from business startups, bankers, lawyers etc etc…

Send proposals of talks to: [email protected]• speaker and affiliation• title of your presentation• 2-5 lines executive summary

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• 10+ pages of supporting material: sample slides, white paper, etc – to evaluate the quality/pertinence of your talk.

• time requested: 15 min / 30 min / 45 min.

Student s planning to do an M.Sc. Thesis on bitcoin are expected to deliver 2 short 15 min. talks before they are accepted to do their thesis on bitcoin.

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Crypto Research at UCL

Dr. Nicolas T. Courtois1. cryptologist and

codebreaker

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2. specialist of smart cards (e.g. bank cards, Oyster cards etc…)

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Our Works on BitcoinNicolas Courtois, Marek Grajek, Rahul Naik: The Unreasonable Fundamental Incertitudes Behind Bitcoin Mining, http://arxiv.org/abs/1310.7935

Nicolas Courtois, Lear Bahack:On Subversive Miner Strategies and Block Withholding Attackin Bitcoin Digital Currency http://arxiv.org/abs/1402.1718

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in Bitcoin Digital Currency http://arxiv.org/abs/1402.1718

Nicolas Courtois, Lear Bahack:On Subversive Miner Strategies and Block Withholding Attackin Bitcoin Digital Currency http://arxiv.org/abs/1402.1718

Nicolas T. Courtois, Pinar Emirdag and Daniel A. Nagy:Could Bitcoin Transactions Be 100x Faster? will appear in SECRYPT 2014, 28-30 August 2014, Vienna, Austria.

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Controversy Around Our Recent Paper:

https://bitcointalk.org/index.php?topic=600436.0;all

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Acknowledgments

The following people have helped to develop the slides [e.g. providing feedback]:

George Danezis, Gerald Davis, Pinar Emirdag, Michael Folkson, Marek Grajek and Tim Swanson.

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Slides 01234 etc..: www.want2pay.com

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Introducing Bitcoin

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Bitcoin In A Nutshell

• bitocoins are cryptographic tokens – stored by people on their PCs or mobile phones

• ownership is achieved through digital signatures: – you have a certain cryptographic key, you have the money. – publicly verifiable, only one entity can sign

• consensus-driven, a distributed system which has no central authority– but I will not claim it is decentralized, this is simply not true!

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– but I will not claim it is decentralized, this is simply not true! – a major innovation is that financial transactions CAN be executed and policed without

trusted authorities. Bitcoin is a sort of financial cooperative or a distributed business.

• based on self-interest: – a group of some 100 K people called bitcoin miners own the bitcoin “infrastructure”

which has costed about 0.5-1 billion dollars (estimation) – they make money from newly created bitcoins and fees – at the same time they approve and check the transactions. – a distributed electronic notary system

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Two Key Concepts

• initially money are attributed through Proof Of Work (POW)to one public key A

– to earn bitcoins one has to “work” (hashing) and consume energy (pay for electricity)– in order to cheat one needs to work even much more (be more powerful than the whole

network, for a short while)

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network, for a short while)

• money transfer from public key A to public key B:– like signing a transfer in front of one notary whic h confirms the

signature ,

– multiple confirmations: another notary will re-confirm it, then another, etc…– we do NOT need to assume that ALL these notaries are honest.

• at the end it becomes too costly to cheat

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Money Transfer

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Crypto Currencies

In Practice

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Payment and Crypto Currencies

Who AcceptsBitcoin?

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Full P2P Clienthttp://bitcoin.org/en/download

15 giga, 24 hours…

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Mobile Apps - Android

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