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Smart contracts in a public ledger system are a predicate-- Bitcoin's creator understood this. They take input-- about the transaction, and perhaps the chain-- and they accept or reject the update to the system. The network of thousands of nodes all around the world doesn't give a _darn_ about the particulars of the computation, they care only that it was accepted. The transaction is free to provide arbitrary side information to help it make its decision.Deciding if an arbitrarily complex condition was met doesn't require a turing complete language or what not-- the verification of a is in P not NP.In Bitcoin Script, we do use straight up 'computation' to answer these questions; because that is the simplest thing to do, and for trivial rule sets, acceptably efficient. But when we think about complex rule-- having thousands and thousands of computers all around the world replicate the exact same computation becomes obviously ludicrous, it just doesn't scale.Fortunately, we're not limited to the non-scalablity-- and non-privacy-- of making the public network repeat computation just to verify it. All we have to do is reconize that computation wasn't what we were doing from the very beginning, verification was!This immediately gives a number of radical improvements:"The program is big and I don't want to have to put it in the blockchain in advance." -> P2SH, hash of the program goes into the public key, the program itself ends up being side information."The program is big but we're only going to normally use one Nth of it-- the branches related to everything going right" -> MAST, the program is decomposed into a tree of ORs ans the tree is merkelized. Only the taken OR branches ever need to be made public; most of the program is never published which saves capacity and improves confidentiality."The program is big, and there are fixed number of parties to the contract. They'll likely cooperate so long as the threat of the program execution exists." -> Coinswap transformation; the entire contract stays outside of the blockchain entirely so long as the parties cooperate."The program is big, and there are fixed number of parties to the contract, and I don't care if everything just gets put back to the beginning if things fail." -> ZKCP; run _arbitrary_ programs, which _never_ hit the blockchain, and are not limited by its expressive power (so long as it supports hash-locked transactions and refunds.)"The program is kinda big, and we don't mind economic incentives for enforcement in the non-cooperative case" -> challenge/response verification; someone says "I assert this contract accepts," and puts up a bond. If someone disagrees, they show up and put up a bond to say it doesn't. Now the first party has to prove it (e.g. but putting the contract on the chain) or they lose their bond to the second party, if they're successful they get the bond from the second party to pay the cost of revealing the contract."The program is too big for the chain, but I don't want to depend on economic incentives and I want my contract to be private." -> ZKP smart contracts; PCP theorem proves that a program can be proved probabilisticly with no more data than log the size of its transcript. SNARKS use strong cryptographic assumptions to get non-interactive proofs for arbitrary programs which are constant size (a few hundred bytes). Slowness of the prover (and in the case of snarks, trusted setup of the public key-- though for fixed sets of participants, this can be avoided) limit the usefulness today but the tech is maturing.All of these radical improvements in scalablity, privacy, and flexibility show up when you realize that "turing complete" is the wrong tool, that what our systems do is verification, not computation. This cognitive error confers no advantage, outside of marketing to people with a fuzzy idea of what smart contracts might be good for in the first place.More powerful smart contracting in the world of Bitcoin will absolutely be a thing, I don't doubt. But the marketing blather around ethereum isn't power, it's a boat anchor-- a vector for consensus inconsistency and decentralization destroying resource exhaustion and incentives mismatches. Fortunately, the cognitive framework I've described here is well understood in the community of Bitcoin experts.
Blockchain, also referred to as distributed ledger, has captured the interest of business leaders, governments, academics and tech providers across the globe. The potential impact of blockchain is significant across all sectors/industries – from banking to government to healthcare and beyond. We think blockchain has the potential to be as significant as the internet, cloud computing, or mobile paradigms by enabling our customers to simplify and transform their current processes.
The term “other token” refers to any asset with a digital representation such media, copyright, currently, credits, mileage, votes, etc.
Blockchain as a Distributed Ledger has four advantages, Security – everything in the Blockchain is encrypted with digital signing. Shared – The real benefits of Blockchain (over conventional technology) are achieved when we use it to link organisations to share information on a distributed ledger. Distributed – a Blockchain can be distributed across multiple organisations and becomes more secure as replicas are added. Ledger – Every transaction written into the ledger once and cannot be changed after the fact. This has great advantages to the financial services industry because we have an auditable trace of every transaction. The compliance overheads for Financial Services have escalated since the financial crash and this feature of the technology has huge benefits for compliance teams and financial regulators
In 2016, Gartner has included Blockchain in their Hype Cycle for Emerging Technologies.
Traditional ledgers use middlemen to approve and record trasnactions. BlockChain safely distributs ledfgers across the entire network. Technology maintains multiple replicas (like P2P torrent files)
Tutorial on BlockChain and ICO in Commodity Trading
By Adj. Prof. Giuseppe Mascarella
1. What are Blockchain, BitCoin, ICOs?
2. Commodity Trading ICO
BLOCKCHAIN AND ICO
Value Amplify Consulting Confidential
1. What is bitcoin and blockchain?
ValueAmplify Consulting Confidential
Value Amplify Consulting Confidential
A. The term Bitcoin is used to refer to 3 things:
The set of technology, concepts and platform
The protocol for using this technology platform to move
value between peers (1 -8 MB block size record)
The currency (BTC) for transactions using this protocol.
B. The term Blockchain is used for
The underlying public ledger technology platform,
needed also for cryptocurrencies.
C. The term Smart Contract refers to
The scripting system on a public ledger, that instead of
just sending currency, sends contractual rights and
obligations - including the terms for payment and delivery
of goods and services - that can be automatically executed
by an autonomous system that’s trusted by all
1. What is BitCoin?
Example: House Ledger
Even if 30% of title have errors, it is better than peer managed
What Problem Are We Addressing?
Global Peer-To-Peer Trust!
Blockchain is a type of distributed ledger
in which value exchange transactions (in
bitcoin or other token) are sequentially
grouped into blocks. Each block is
chained to the previous block and
immutably recorded across a peer-to-peer
network, using cryptographic trust and
assurance mechanisms. Depending on the
implementation, transactions can include
Source: Gartner IT Glossary http://www.gartner.com/it-glossary/blockchain/
merging Technologies http://www.gartner.com/newsroom/id/3412017
What is blockchain?
In business terms:
Disintermediating accountants, auditors,
lawyers, public notary, banks, etc with an
army of fast robots checking up on each
others' work to secure compliance.
It provides a peer-to-peer technology through which a
transaction of value can be done in a secure manner,
without the need of a third party (i.e. a bank, a notary)
Proof: Blockchain explorer allows viewing of latest
transactions posting to the Public Ledger
Not all blockchain are
public. B2B solution can
ValueAmplify Consulting Confidential
What is an ICO?
ICO means: Initial Coin Offer
ICOs are a type of crowdfunding or crowd investing tool conducted entirely on the
Originally, the main idea of an ICO was to fund new projects by pre-selling coins/tokens
to investors interested in the project.
Entrepreneurs present a whitepaper describing the business model and the technical
specifications of a project before the ICO.