Prof Willy Susilo presented a seminar titled "Blockchain and its Applications" as part of the SMART Seminar Series on 20th September 2018.
More information: https://news.eis.uow.edu.au/event/blockchain-and-its-applications/
Keep updated with future events: http://www.uoweis.co/events/category/smart-infrastructure-facility/
In this presentation we try to extend the capabilities of traditional cryptography from single user to multiple distrusting parties who wants to mutually evaluate a joint function by keeping their inputs as PRIVATE as possible and obtaining a FAIR and CORRECT output. Immediate applications of Secure Multi-Party Computation includes Detecting and Preventing Satellite Collision of between nations, Privacy Preserving Data Mining and Analysis, Secure e-autcion and e-voting etc.
With a transaction fee market and without a block size limit in Bitcoin netwo...ijgttjournal
International Journal of Game Theory and Technology ( IJGTT) is an open access peer -reviewed journal that helps bridge together both the research and development aspects of games theory and technology. Game theory is an inter-disciplinary field that focuses on studying games, creating innovative architectures and explores new ideas to develop games which can be used for learning purposes. This journal provides a platform for exchanging ideas in new emerging trends that needs more focus and exposure and will attempt to publish proposals that strengthen our goals.
Identity-based threshold group signature scheme based on multiple hard number...IJECEIAES
We introduce in this paper a new identity-based threshold signature (IBTHS) technique, which is based on a pair of intractable problems, residuosity and discrete logarithm. This technique relies on two difficult problems and offers an improved level of security relative to an on two difficult hard problems. The majority of the denoted IBTHS techniques are established on an individual difficult problem. Despite the fact that these methods are secure, however, a prospective solution of this sole problem by an adversary will enable him/her to recover the entire private data together with secret keys and configuration values of the associated scheme. Our technique is immune to the four most familiar attack types in relation to the signature schemes. Enhanced performance of our proposed technique is verified in terms of minimum cost of computations required by both of the signing algorithm and the verifying algorithm in addition to immunity to attacks.
Blockchain concept and technology. How this is becoming the next trend after the Bitcoin, expanding to a myriad of solutions. Smart contracts might be using a public distributed, and encrypted platform to support data persistence.
A Quick Start To Blockchain by Seval CaprazSeval Çapraz
Blockchain is one of the most innovative discoveries of the past century.
The first cryptocurrency, Bitcoin, was proposed in 2008 by Satoshi Nakamoto with a white paper.
In this presentation we try to extend the capabilities of traditional cryptography from single user to multiple distrusting parties who wants to mutually evaluate a joint function by keeping their inputs as PRIVATE as possible and obtaining a FAIR and CORRECT output. Immediate applications of Secure Multi-Party Computation includes Detecting and Preventing Satellite Collision of between nations, Privacy Preserving Data Mining and Analysis, Secure e-autcion and e-voting etc.
With a transaction fee market and without a block size limit in Bitcoin netwo...ijgttjournal
International Journal of Game Theory and Technology ( IJGTT) is an open access peer -reviewed journal that helps bridge together both the research and development aspects of games theory and technology. Game theory is an inter-disciplinary field that focuses on studying games, creating innovative architectures and explores new ideas to develop games which can be used for learning purposes. This journal provides a platform for exchanging ideas in new emerging trends that needs more focus and exposure and will attempt to publish proposals that strengthen our goals.
Identity-based threshold group signature scheme based on multiple hard number...IJECEIAES
We introduce in this paper a new identity-based threshold signature (IBTHS) technique, which is based on a pair of intractable problems, residuosity and discrete logarithm. This technique relies on two difficult problems and offers an improved level of security relative to an on two difficult hard problems. The majority of the denoted IBTHS techniques are established on an individual difficult problem. Despite the fact that these methods are secure, however, a prospective solution of this sole problem by an adversary will enable him/her to recover the entire private data together with secret keys and configuration values of the associated scheme. Our technique is immune to the four most familiar attack types in relation to the signature schemes. Enhanced performance of our proposed technique is verified in terms of minimum cost of computations required by both of the signing algorithm and the verifying algorithm in addition to immunity to attacks.
Blockchain concept and technology. How this is becoming the next trend after the Bitcoin, expanding to a myriad of solutions. Smart contracts might be using a public distributed, and encrypted platform to support data persistence.
A Quick Start To Blockchain by Seval CaprazSeval Çapraz
Blockchain is one of the most innovative discoveries of the past century.
The first cryptocurrency, Bitcoin, was proposed in 2008 by Satoshi Nakamoto with a white paper.
201803 Blockchains, Cryptocurrencies & Tokens - NYC Bar Association Presentat...Paperchain
Presented at the NYC Bar Association, an overview of the technologies that make up blockchain technology and why those technologies have implications with existing legal frameworks.
Virtual or digital currencies, with Bitcoin chief amongst them, have been gaining momentum and investment over the last couple of years. Offering an almost costless means of making payments around the globe, virtual currencies have the potential to bring significant disruption to the banking industry. This potential is not lost on either Bitcoin startups or banks themselves. But how does Bitcoin actually work? A peer-to-peer network maintains the “blockchain”, an innovative cryptographic protocol which securely mediates payments between parties without mutual trust. This session will step through the structure of the blockchain, showing how it solves the “double spend” problem and allows decentralised processing of financial transactions. Whether Bitcoin will become the currency of the internet or it’s a bubble that is doomed to burst sooner or later, the blockchain itself will change the face of transactional banking and perhaps other industries along the way.
Presentation to the Sydney Financial Mathematics Workshop (11 March 2015)
http://www.qgroup.org.au/content/bitcoin-banking-and-blockchain
This presentation gives you the sense on what is Blockchain and how does work
Blockchain is the technology that can disrupt economies by decentralizing , democratizing trust and eliminating unnecessary intermediaries using the TRUST protocol!
(Note: All numbers / brands / currencies used in these slides are for demonstration purposes)
Blockchain, cryptography and tokens — NYC Bar presentationPaperchain
Concise version of presentation delivered at the NYC Bar Association.
Overview of blockchains, how cryptography works on blockchains and the difference between cryptocurrencies and tokens.
Introduction to blockchain and cryptocurrency technologiesPaweł Wacławczyk
Introduction to cryptography primitives and fundamental data structures. Discuss the process of achieving distributed consensus, proof-of-work and potential attacks on network.
Creating an In-Aisle Purchasing System from ScratchJonathan LeBlanc
The future of retail is in removing the divide between the offline shopping state and the enhanced online buying experience. To create this type of enhanced retail experience, we can remove complexities in the process, such as simplifying checkout.
In this session we’ll learn how to use internet-connected microelectronics to attach to a buyer’s mobile device to provide the functionality to buy products right from the aisle.
Richard Skarbez presented a seminar titled "Cognitive Illusions in Virtual Reality: What do I mean? And why should you care?" as part of the SMART Seminar Series on the 4th March 2019.
More information:
https://news.eis.uow.edu.au/event/cognitive-illusions-in-virtual-reality-what-do-i-mean-and-why-should-you-care/
Keep updated with future events: http://www.uoweis.co/events/category/smart-infrastructure-facility
Dr Ricardo Peculis presented a seminar titled "Trusted Autonomous Systems as System of Systems" as part of the SMART Seminar Series on 19th February 2019.
More information:
https://news.eis.uow.edu.au/event/trusted-autonomous-systems-as-system-of-systems/
Keep updated with future events: http://www.uoweis.co/events/category/smart-infrastructure-facility"
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Presented at the NYC Bar Association, an overview of the technologies that make up blockchain technology and why those technologies have implications with existing legal frameworks.
Virtual or digital currencies, with Bitcoin chief amongst them, have been gaining momentum and investment over the last couple of years. Offering an almost costless means of making payments around the globe, virtual currencies have the potential to bring significant disruption to the banking industry. This potential is not lost on either Bitcoin startups or banks themselves. But how does Bitcoin actually work? A peer-to-peer network maintains the “blockchain”, an innovative cryptographic protocol which securely mediates payments between parties without mutual trust. This session will step through the structure of the blockchain, showing how it solves the “double spend” problem and allows decentralised processing of financial transactions. Whether Bitcoin will become the currency of the internet or it’s a bubble that is doomed to burst sooner or later, the blockchain itself will change the face of transactional banking and perhaps other industries along the way.
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This presentation gives you the sense on what is Blockchain and how does work
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Creating an In-Aisle Purchasing System from ScratchJonathan LeBlanc
The future of retail is in removing the divide between the offline shopping state and the enhanced online buying experience. To create this type of enhanced retail experience, we can remove complexities in the process, such as simplifying checkout.
In this session we’ll learn how to use internet-connected microelectronics to attach to a buyer’s mobile device to provide the functionality to buy products right from the aisle.
Richard Skarbez presented a seminar titled "Cognitive Illusions in Virtual Reality: What do I mean? And why should you care?" as part of the SMART Seminar Series on the 4th March 2019.
More information:
https://news.eis.uow.edu.au/event/cognitive-illusions-in-virtual-reality-what-do-i-mean-and-why-should-you-care/
Keep updated with future events: http://www.uoweis.co/events/category/smart-infrastructure-facility
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More information:
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More information: http://www.uoweis.co/event/dealing-with-uncertainty-with-the-observer-in-the-loop/
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http://sandymillin.wordpress.com/iateflwebinar2024
Published classroom materials form the basis of syllabuses, drive teacher professional development, and have a potentially huge influence on learners, teachers and education systems. All teachers also create their own materials, whether a few sentences on a blackboard, a highly-structured fully-realised online course, or anything in between. Despite this, the knowledge and skills needed to create effective language learning materials are rarely part of teacher training, and are mostly learnt by trial and error.
Knowledge and skills frameworks, generally called competency frameworks, for ELT teachers, trainers and managers have existed for a few years now. However, until I created one for my MA dissertation, there wasn’t one drawing together what we need to know and do to be able to effectively produce language learning materials.
This webinar will introduce you to my framework, highlighting the key competencies I identified from my research. It will also show how anybody involved in language teaching (any language, not just English!), teacher training, managing schools or developing language learning materials can benefit from using the framework.
The French Revolution, which began in 1789, was a period of radical social and political upheaval in France. It marked the decline of absolute monarchies, the rise of secular and democratic republics, and the eventual rise of Napoleon Bonaparte. This revolutionary period is crucial in understanding the transition from feudalism to modernity in Europe.
For more information, visit-www.vavaclasses.com
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Macroeconomics- Movie Location
This will be used as part of your Personal Professional Portfolio once graded.
Objective:
Prepare a presentation or a paper using research, basic comparative analysis, data organization and application of economic information. You will make an informed assessment of an economic climate outside of the United States to accomplish an entertainment industry objective.
4. Traditional View of Digital Currency
Bank
Payer Payee
Account
Establishment
Generate
an e-coin
Spend an
e-coin
Deposit
an e-coin
5. Traditional View of Digital Currency
Bank
Payer Payee
Account
Establishment
Generate
an e-coin
Spend an
e-coin
Deposit
an e-coin
Remove the
central party
7. Bitcoins revisited
• Bitcoin is a cryptocurrency, existing purely in
the digital realm – first deployed in 2009.
• Cryptocurrency: a currency built upon computer
science, cryptography and economics.
• Born out of the Cypherpunk movement – a
libertarian fight for privacy and self-governance.
• The inspiration for the invention of the
blockchain.
• Created by Satoshi Nakamoto (anonymous ID)
8. What is Blockchain?
• A chain of blocks
• Public ledger/database
• Records all transactions across P2P network
• Shared between participants
18. Ingredient #1: Hashes
• A hash function (like SHA-256) takes a block
of data in, and produces an effectively random
fixed size integer.
• Any change to the input randomizes it
SHA-256
“The quick brown fox did some crypto”
410312395834291203…
SHA-256
“The quick brown Fox did some crypto”
983249120432492340…
19. Hash property 1: Collision-free
• Nobody can find x and y such that
• x != y and H(x)=H(y)
x
y
H(x) = H(y)
20. • Collisions do exist ...
• … but can anyone find them?
possible inputs
possible outputs
21. Hash property 2: Hiding
• Hiding property:
• If r is chosen from a probability
distribution that has high min-entropy,
then given H(r | x), it is infeasible to
find x.
• High min-entropy means that the
distribution is “very spread out”, so
that no particular value is chosen with
more than negligible probability.
22. Hash property 3: Puzzle-friendly
• Puzzle-friendly:
• For every possible output value y,
• if k is chosen from a distribution
with high min-entropy,
• then it is infeasible to find x such
that H(k | x) = y.
23. Application: Search puzzle
• Given a “puzzle ID” id (from high min-entropy
distrib.),
• and a target set Y:
• Try to find a “solution” x such that
• H(id | x) ∈ Y.
• Puzzle-friendly property implies that no solving
strategy is much better than trying random
values of x.
24. SHA-256 hash function
256 bits 256 bits
512 bits
Theorem: If c is collision-free, then SHA-256 is
collision-free.
Padding (10* | length)
IV
Message
(block 1)
Message
(block 2)
Message
(block n)
Hash
c c c
25. Consensus--Hash-based Proof of Work
• To find a hash with N zeros at the start of the input,
requires 2N computations…proves computational work
• If we hash an incrementing “nonce” as the hash input,
we can go looking for zeros:
in 3e-05 seconds, nonce = 0 yielded 0 zeros. value =
4c8f1205f49e70248939df9c7b704ace62c2245aba9e81641edf…
in 0.000138 seconds, nonce = 12 yielded 1 zeros. value =
05017256be77ad2985b36e75e486af325a620a9f29c54…
in 0.000482 seconds, nonce = 112 yielded 2 zeros. value =
00ae7e0956382f55567d0ed9311cfd41dd2cf5f0a7137…
in 0.014505 seconds, nonce = 3728 yielded 3 zeros. value =
000b5a6cfc0f076cd81ed3a60682063887cf055e47b…
in 0.595024 seconds, nonce = 181747 yielded 4 zeros. value =
0000af058b74703b55e27437b89b1ebcc46f45ce55d6….
in 3.491151 seconds, nonce = 1037701 yielded 5 zeros. value =
00000e55bd0d2027f3024c378e0cc511548c94fbeed0e….
in 32.006105 seconds, nonce = 9913520 yielded 6 zeros. value =
00000077a77854ee39dc0dc996dea72dad8852afbde6….
26. PoW property 1: difficult to compute
~about 1020 hashes/block
Only some nodes bother to compete —
miners
27. PoW property 2: parameterizable cost
Nodes automatically re-calculate the target every
two weeks
Goal: average time between blocks = 10 minutes
Prob (Alice wins next block) =
fraction of global hash power she controls
29. PoW property 3: trivial to verify
Nonce must be published as part of block
Other miners simply verify that
H(nonce ‖ prev_hash ‖ tx ‖ … ‖ tx) < target
31. The Nonce / Hash Loop
• The algorithm to make a new block:
1. Verify the hashes of all the previous blocks
2. Build a new block with a random nonce
3. Hash the new block. Does it have N zeros?
– No? Go back to Step 2
– Yes? Send your new block to everyone!
• Note that as a result of step #1, you can find
out how many points anyone has by counting
how many blocks they have won
32. Ingredient #2: Signatures
Signing key
Public part 454F4D3E1..
Private part 56F23F2D..
Data
Signing
Algorithm
Signature
Private part
Signature
Verification
Algorithm
Yes/No
Public part
Data
33. What we want from signatures
• Only you can sign, but anyone can verify
• Signature is tied to a particular
document
• can’t be cut-and-pasted to another doc
34. API for digital signatures
• (sk, pk) := generateKeys(keysize)
• sk: secret signing key
• pk: public verification key
• sig := sign(sk, message)
• isValid := verify(pk, message, sig)
can be
randomized
algorithms
35. Requirements for signatures
• “valid signatures verify”
• verify(pk, message, sign(sk, message)) == true
• “can’t forge signatures”
• adversary who:
• knows pk
• gets to see signatures on messages of his choice
• can’t produce a verifiable signature on another message
36. • Bitcoin uses ECDSA standard
• Elliptic Curve Digital Signature Algorithm
• relies on hairy math
• will skip the details here --- look it up
if you care
37. Incentive 1: block reward
Creator of block gets to
• include special coin-creation transaction in the block
• choose recipient address of this transaction
Value is fixed: currently 12.5 BTC, halves every 4 years
Block creator gets to “collect” the reward only if the
block ends up on long-term consensus branch!
Mechanism: Incentive
38. Incentive 2: transaction fees
Creator of transaction can choose to make
output value less than input value
Remainder is a transaction fee and goes to
block creator
Purely voluntary, like a tip
39. Where are the rules?
• The laws of Bitcoin (or any blockchain)
are in the miner nodes
– Whatever 51% of the miners are running will
win
• The source to the node are the law
• How do you change rules?
• What happens if:
– The crypto breaks?
– We want to add more coins?
– We want to change the block format?
40. Attacks
• What happens if the majority of
the players defect?
– 51% attacks – can extend bad blocks
• How large a body needs to defect?
– Depending on network, can be 30% or
less
– Sybil attacks
48. 4848
Existing methods to trace
Based on transaction analysis
• Clustering algorithms, graph theory and
data analysis
Based on a central party
• RScoin and Solidus
Based on cryptographic tools
• Accountable DAP and our proposal
64. Before
After, with Bitcoin
You Your money
at the bank intermediaries
Fees, slow, closed
Their bank
Other people
and business
You
The Bitcoin networks
Open, peer-to-peer, instant, free
Other people
and business
65. You Your money
at the bank
intermediaries
Fees, slow, closed
Their
bank Other
people and
business
The Bitcoin networks
Open, peer-to-peer, instant, free
intermediaries
Fees, slow, closed