Free Blockchain BTA Certified Blockchain Solution Architect Exam Dumps

The gas price is a value set by the creator of the transaction, who has to pay gas_price * gas up front from the sending account. If some gas is left after the execution, it is refunded in the same way. If the gas is used up at any point (i.e. it is negative), an out-of-gas exception is triggered, which reverts all modifications made to the state in the current call frame.

Hyperledger Composer has following main components:

1) Business Network Archive: Capturing the core data in a business network, including the business model, transaction logic, and access controls, the Business Network Archive packages these elements up and deploys them to a runtime. Business Network Archive files are stored as ''.bna'' files.

2) Composer Playground: This web-based tool allows developers to learn Hyperledger Composer, model out their business network (domain), test that network, and deploy that network to a live instance of a blockchain network. The playground keeps the development model in browser storage, allowing them to be easily uploaded or downloaded. The playground also allows for CRUD (create, read, update, delete) operations to be performed on asset transactions which are created and logged. Composer playground offers a repository of sample business networks that can provide a base for building your own business network

Remember, that the block creation time is set to 10 minutes and this can never change. So after a fixed time of approximately 2 weeks or exactly 2016 blocks the difficulty is re-adjusted. Increase in difficulty means target decreases.

2.0 Ethereum came after Bitcoin. Vitalik Buterin, one of the writers for Bitcoin Magazine that tried to popularize the technology in the early 2012. He witnessed first-hand the problems in the Bitcoin implementation like wasteful mining hardware, centralized mining community, and lack of network scalability. In 2013, the then 19 year old Vitalik described his vision for Ethereum by extending the concept of Bitcoin beyond just currency. He proposed a platform where developer community and entrepreneurs to build distributed application (Dapps) for the Blockchain network. He referred to this concept of trust beyond just currency as 'smart contracts' or even blockchain-based ''decentralized autonomous organizations'' (DAOs).

In 2008 a whitepaper is published by ''Satoshi Nakamoto'' which outlines a solution to the Byzantine Generals problem

Business logic -- something isn't right according to business requirements Security -- the code is vulnerable to some security exploits Regression -- some code updates caused existing features to break Performance -- the code is slow or some actions execute extra functions