Mythril is an open-source security analysis tool for EVM bytecode, courtesy of ConsenSys. It is also a component of their Security Analysis Service – Mythx. Mythril detects security vulnerabilities in smart contracts built for Ethereum and other EVM-compatible blockchains. Vulnerabilities found by Mythril are reported with reference to the weaknesses listed on the Smart Contract Weakness Classification Registry (SWC Registry). I will use two entries from SWC Registry for the examples in this article: SWC-106 – Due to missing or insufficient access controls, malicious parties can self-destruct the contract. SWC-107 – One of the major dangers of calling external contracts is that they can take over the control flow. In the reentrancy attack (a.k.a. recursive call attack), a malicious contract […]
KhelCoin (KHEL) is an ERC-20 token available on Ethereum blockchain. It is a Smart Contract created with Solidity, OpenZeppelin, Truffle, Ganache, Remix, web3.js and VSCode. It is currently available on Rinkeby test network. It will be launched on the Mainnet in the near future. You can get KHEL coins from this website – KHEL Coin ICO Head over to the ICO website. You will be prompted to install Metamask and connect to your account on Rinkeby testnet. Click on “Buy KHEL Coins” button to get your own coins! Source code is on github – https://github.com/ashtewari/khelcoin Puzzle Icon Credit: https://www.flaticon.com/free-icons/puzzle
Washington DC – May 2019 In this session, we will introduce you to the world of Blockchain technology. We will start with the fundamentals and explain the characteristics and use cases of Blockchains and Decentralized applications. We will explain public Blockchains as well as permissioned Blockchains – with examples from Ethereum and Hyperledger. You will learn how to create a private blockchain to get started. You will learn about Ethereum and how to program Smart Contracts for Ethereum Blockchain. We will also share best practices for secure and effective Smart Contracts development. Image Credit: Davidstankiewicz, Blockchain Illustration 2, CC BY-SA 4.0
TRINUG – Main Meeting : Programming Smart Contracts on Ethereum Blockchain – August 2018 In this session, Ash will introduce you to the world of Blockchain programming. You will learn about Ethereum and how to program Smart Contracts for Ethereum Blockchain. You will learn how to deploy and test your Contracts on a public Ethereum Testnet. Ash will share best practices for Smart Contract development. You will be able to participate in a hands-on walk-through in the latter half of the session.
Charlotte IOT – July 2018 You will not want to miss this chance to learn about Blockchain, a technology enabling an entire IoT ecosystem! It has a distributed database for all the transactions, which eliminates the need for the third party to authenticate the transactions. The database ledger is a continuously growing list of records, called blocks, which are linked and secured using cryptography. Charlotte IoT wants to thank Ash Tewari for traveling from Raleigh to share his extensive knowledge and experience around Blockchain. In this session, Ash will introduce you to the world of Blockchain programming. You will learn about Ethereum and how to program Smart Contracts on Ethereum Blockchain. You will learn how to deploy and test your code on a public Ethereum […]
Permissioned blockchains are being developed and used in Enterprise scenarios in which higher transaction throughput, lower latency, versatile confidentiality and governance models are more important than supporting low trust levels among participants. These Enterprise requirements are not being met adequately by the public and permission-less blockchain ledgers. Enterprise scenarios typically have known actors and the trust level between these actors is very high. This allows for trade-offs between trust levels and transaction throughput, speed, confidentiality and privacy, which in turn enables alternate solutions via permissioned blockchains. Hyperledger Fabric (referred to as ‘Fabric’ in the rest of this article) is the leading permissioned blockchain framework, initially developed by IBM. There are other players in this space, including Multichain, ChainCore and the relatively […]