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Blockchain-based Provably Fair Betting

Our progress is far better than expected in developing a workaround for random number generation under blockchain environment! Here is the brief description how it works.

If you have installed MetaMask in Chrome or Firefox, welcome to have a try in this technical demo by switch to Ropsten testnet:

https://eth888.io/game1-ropsten/

You may get some Ethers from this faucet:

http://faucet.ropsten.be:3001/


There are three major concerns in design:

convince the players that the decision made by the platform was before themplayers can contribute their inputs to affect number generationplayers are unable to control the resultFor point 1, we provide a SHA256 encrypted hash to the players before any bets placed. The key to this hash actually is a random server-side seed (a long random string) generated from a centralized world (a private client node in Ethereum network). The seed is already stored in a private database (no public end-point). Once result available, the server-side seed will be availab…

Adding Vanil tokens to your wallet

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MyEtherWallet


Select "Send Ether & Tokens" section in the top tab bar.



On the lower right hand side, click "Add Custom Token".



Fill in three fields:

Address: 0x748183ca2e34279579ae21b16f93dcd3bbe3e3ed

Token Symbol: VAN

Decimals: 18



Afterwards, Click Save.



It shows the balance of yours Vanil tokens.


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MetaMask


Select "TOKENS" tab.



Fill in three fields:

Token Contract Address: 0x748183ca2e34279579ae21b16f93dcd3bbe3e3ed

Token Symbol: VAN

Decimals of Precision: 18




Afterwards, Click Save.



It shows the balance of yours Vanil tokens.







It is so exciting!

Hello everyone,

We are today so excited to announce that ETH888's stage 1 ICO already started today!

You are welcome to understand and be clear the concept before contributing. Please let us know if you have any questions in mind, so hope that we can make it clear to all of you!

THANKS!

Contract Source

In order to comply with blockchain's rationale, we are glad to share all contract codes in GitHub:

https://github.com/eth888/Crowdsale-Stage-1-Contracts

Welcome to take a look and comment it if any!

公平結果驗證

網上博彩最容易被大眾標籤的地方是結果產生欠透明度,公平性成疑。如何有效建立彼此的信任,是長遠經營成功的關鍵!這裡會分享一下,一個非常有趣而且聰明的數學方法去針對這方面需要。

首先,在數學層面,有一項加密方式叫SHA256,它是由美國國家安全局於2008年所發表的,詳細資料可按這裡。它的特色是,可以把任何字串句子,加密成一串長32個字母混合數字的字串,例如:

把"Hello"加密成:

"185f8db32271fe25f561a6fc938b2e264306ec304eda518007d1764826381969"

但如果我們輕輕把"Hello"改成"Hella",那結果將會是完全不同:

"62197ce641a17c96cf39ed51e72e86fd486f3de7b0135f8b8f0f7364dc010e54"

試嘗加密其他可到這裡

而且,有一個非常重要的特性,就是這個加密是單向的!即是說,如果我們只有加密後的結果,是無法運算出原本的字串,唯一方法是隨機撞中,但那需要極多的時間,或極大的hashing power,這大概是不可行。

正正應用以上特性,遊戲的結果可以結合伺服器方的秘密種子(即"Hello")及由玩家提供的輸入/隨機字串所產生,而在下注及結果產生之前,伺服器方會把已加密的結果字串("185f8db32271fe25f561a6fc938b2e264306ec304eda518007d1764826381969"),傳給玩家作記錄。當結果公怖後,伺服器方的秘密種子("Hello")也隨之公開,那玩家就可以利用SHA256加密工具去驗證一次,那秘密種子加密後,是不是跟"185f8db32271fe25f561a6fc938b2e264306ec304eda518007d1764826381969"一致。如果是,那代表,"Hello"是在結果產生及下注前已經存在,而不是針對自己的下注決定所產生出來欺騙玩家。






Smart Contract and Random Number

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It is really awesome that Ethereum support easy-deployment of smart contract by individual developers! The language / script is using called Solidity.

However, unlike coding in ordinary environment, it is running in blockchain network, so we don't have a function simply to seed and generate numbers, as all outputs from blockchain network are deterministic.
Blockhash
This is an approach for games which are merely for fun or with a relatively small bet, as its number generation algorithm is transparent and shown in the smart contract and also its inputs, like blockhash (an unique long text for labelling a block) and block number (completely deterministic). Normally, blockhash is unpredictable but if the bet is extremely large or worthy, miners can choose to whether publish a new block to the network, so they can have some degrees of control in blockhash generation for result manipulation. Here is a simple:
contract random { /* Generates a random number from 0 to 100 based on the l…

Ethereum is a destructive stuff for web3!

With the growth of blockchain technology, it keeps changing the world. It makes our Internet be more transparent and having higher level of security. 
In recent years, Bitcoin creates lots of discussions and critics. People in general associate it with illegal activities and evil money, but actually it is a very very realistic example in the success of blockchain application in real world!
Please note that, blockchain is not equal of Bitcoin, but Bitcoin's operation relies on blockchain technology. Similarly, Bitcoin is not an only crytocurrency but many many alternative coins do exist. For example Litecoin, Ripple and Dogecoin are quite popular. An indispensable one, Ethereum, a very promising public blockchain infrastructure in the coming future! It allows individual developers deploying smart contract to a sophisticated public network in which stakeholders of a contract all understand the contract details, things fairly without cheating, an awesome environment to replace ordin…