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the age of cryptocurrency at Devoxx Morocco
1. #DevoxxCoin
By BELLAJ Badr
Twitter @badrbellaj
The Age of Cryptocurrency
Developers Let’s Discover A new
opportunity
Bellaj.badr@gmail.com
Linkedin.com/in/bellajbadr
2. Twitter @Badrbellaj#DevoxxCoin
The Age of Cryptocurrency
•Money is …..?
•In Math 𝑥 + 𝑎 𝑛 = 𝑘=0
𝑛 𝑛
𝑘
𝑥 𝑘 𝑎 𝑛−𝑘 we trust.
•What is the Crypto-currency?
•How it works (Bitcoin)?
•Behind the scene(Block Chain Technology)
•Start coding for Bitcoin/BC
•Demo.
9. Twitter @badrbellaj#DevoxxCoin
Paper money was introduced in China during the 11th
century.
In the 13th century, paper money became known in
Europe.
PAPER ..No Way????
Currency Evolution
The problems begins :(
11. Twitter @badrbellaj#DevoxxCoin
inflation/diflation
the Vietnam War and persistent balance of payments deficits, led U.S.
President Richard Nixon to end international convertibility of the U.S.
dollar to gold on August 15, 1971
Governments (banks) prints easily money to pay debts, pay more salaries …
without regard for a stable currency.
15. Twitter @badrbellaj#DevoxxCoin
In a god they trust
I have no trust in the god they trust
• Inflation
• Slow transfers (2 business days)
• Expensive transfers
• Ease of seizure
• local
19. Twitter @badrbellaj#DevoxxCoin
A digital currency in which encryption techniques are used to
regulate the generation of units of currency and verify the
transfer of funds, operating independently of a central bank
within a peer to peer network.
We trust in Math/ Encryption
20. Twitter @badrbellaj#DevoxxCoin
• In 2008 A whitepaper was
posted on the internet by
Satoshi Nakamoto
titled Bitcoin: A Peer-to-Peer
Electronic Cash System. It
described a sytem of
cryptocurrency that was not
backed by any government or
any form of existing currency.
Bitcoin ("BTC") since 2008
21. Twitter @badrbellaj#DevoxxCoin
• Bitcoin is an Open-Source project (software)
• The most successful & the first fully implemented
crypto currency.
• Bitcoin is a peer to peer Network (over internet) and a
Currency base.
Bitcoin
23. Twitter @badrbellaj#DevoxxCoin
Public key cryptography was
invented in the 1970s and is a
mathematical foundation for
computer and information security
In Math we trust
We trusts
In something (gold) we trusts In someone (bankers) we trusts
31. Twitter @badrbellaj#DevoxxCoin
Proof of Work
To get paid for their hash, a miner must find a hash that starts with a certain sequence.
(for example, 000)
This extends the amount of time the miner must spend on each block (avoid inflation)
39. Twitter @Badrbellaj#DevoxxCoin
Get started with BitcoinJ
You can download the library as a JAR, or use Maven, or get the code from
github.
Documentation : https://bitcoinj.github.io/javadoc/0.13.3/
bitcoinj is a library for working with the Bitcoin protocol. It
can maintain a wallet, send/receive transactions without
needing a local copy of Bitcoin Core and has many other
advanced features
40. Twitter @Badrbellaj#DevoxxCoin
BitcoinJ Sample
final NetworkParameters params = RegTestParams.get();
final DumpedPrivateKey dumpedPrivateKey = new DumpedPrivateKey(RegTestParams.get(),
"cQWVW6Vj3E7qEH4DSxN5HGcE29YTPQhpKBzJGXEcQ7LtWtEZ9YGK");
final ECKey key = dumpedPrivateKey.getKey();
System.out.println("BTC address that will be added: " +
key.toAddress(RegTestParams.get()));
System.out.println("Private key that will be added: " +
key.getPrivateKeyEncoded(RegTestParams.get()));
Address addressFromKey = key.toAddress(params);
System.out.println("On the network, we can use this address:n" + addressFromKey);
final WalletAppKit kit = new WalletAppKit(RegTestParams.get(), new File("Doxx"),
"Devoxx BTC") {
protected void onSetupCompleted() {
}
};
42. Twitter @badrbellaj#DevoxxCoin
BTC is 42 000 lines of code only
As of June 30, there
were 6,109 Github
repositories
referencing Bitcoin. By
comparison, there were
2,318 repositories
referencing Paypal.
Cryptocurrencies use decentralized control as opposed to centralized electronic money/centralized banking systems.
The decentralized control is related to the use of bitcoin's block chain transaction database in the role of a distributed ledger.
Decentralized cryptocurrency is produced by the entire cryptocurrency system collectively, at a rate which is defined when the system is created and which is publicly known
Most cryptocurrencies are designed to gradually decrease production of currency, placing an ultimate cap on the total amount of currency that will ever be in circulation.
No corporation or government controls it, and you don’t have to trust any third party with your money. You completely control your money with Bitcoin, and can anonymously and securely send it to anyone else.
Les maths sont incorubtible
NO SPOF
in October 2013, reaching over $1160 by early December. Note how the 2nd Bitcoin bubble on the left side of the price chart is absolutely dwarfed by the 3rd bubble. This is the highest price Bitcoin has ever reached to date
and slowly declined through May 2014 to $440. Alot of the decline can be explained by Mt. Gox collapsing, China trying to ban the Bitcoin trade, and the United States government taking an anti-Bitcoin stance. Currently the price is relatively stable despite all of these factors, and it appears the worst is over.
A VIDEO that explain the notion Behind BTC
Vous pouvez voir en temps reel les transactions en cours
Avez-vous des questions avant de passer au code?
bitcoinj is a library for working with the Bitcoin protocol. It can maintain a wallet, send/receive transactions without needing a local copy of Bitcoin Core and has many other advanced features
there are no situations in which you could sue any of the developers (it's as if you wrote the entire library yourself). If you can't handle that, don't use this library.