Blockchain Android

1.

blockchain includes public blockchain, joint (instry) blockchain and private blockchain. Public chain point-to-point e-cash system: bitcoin, smart contract and decentralized application platform: Ethereum

blockchain is a new application mode of distributed data storage, point-to-point transmission, consensus mechanism, encryption algorithm and other computer technologies

blockchain is an important concept of bitcoin. In essence, it is a decentralized database. At the same time, as the underlying technology of bitcoin, it is a series of data blocks generated by using cryptographic methods. Each data block contains a batch of bitcoin network transaction information, Used to verify the validity of its information (anti-counterfeiting) and generate the next block

extended data

according to the different degree of blockchain network centralization, three kinds of blockchains under different application scenarios are differentiated:

1. The blockchain with the whole network open and without user authorization mechanism is called public chain

2. The authorized nodes are allowed to join the network, and the information can be viewed according to the authority. It is often used in the inter agency blockchain, which is called alliance chain or instry chain

3. All the nodes in the network are in the hands of one organization, which is called private chain

alliance chain and private chain are also called licensing chain, and public chain is called non licensing chain

blockchain features

1, decentralization. Blockchain technology does not rely on additional third-party management institutions or hardware facilities, and there is no central control. In addition to the self-contained blockchain itself, each node realizes information self verification, transmission and management through distributed accounting and storage. Decentralization is the most prominent and essential feature of blockchain

2. Openness. Blockchain technology is based on open source. In addition to the private information of all parties involved in the transaction is encrypted, the data of blockchain is open to everyone. Anyone can query blockchain data and develop related applications through the open interface, so the information of the whole system is highly transparent

3. Independence. Based on consensus specifications and Protocols (similar to various mathematical algorithms such as hash algorithm used by bitcoin), the whole blockchain system does not rely on other third parties, and all nodes can automatically and safely verify and exchange data in the system without any human intervention

4. Safety. As long as 51% of all data nodes cannot be controlled, the network data cannot be arbitrarily manipulated and modified, which makes the blockchain itself relatively safe and avoids subjective and artificial data changes

5. Anonymity. Unless there are legal requirements, technically speaking, the identity information of each block node does not need to be disclosed or verified, and the information can be transferred anonymously

2. Ethereum also uses blockchain technology, but it is more convenient to use than bitcoin's blockchain Turing, which is complete and open source. Anyone can create their own application on the basis of Ethereum

3.

1. Different network architectures:

decentralized application (DAPP) runs on the distributed network, the information of participants is protected (or anonymous), and the decentralized operation is carried out through different people in the network nodes. Distributed network is made up of node computers which are distributed in different places and have multiple terminals. When any line in the network fails, the communication can be completed through other links, which has high reliability

traditional app needs services provided by third-party service providers, and can achieve wireless network access through mobile communication network, which belongs to the centralized network architecture mode

2. Different from open source:

DAPP applications must be open source. Most of the tokens issued by DAPP run independently rather than controlled by an entity. All data and records must be encrypted and stored on a public and decentralized blockchain

traditional app software, games, navigation and other applications are generally provided by third-party service providers, which should solve the problems of right protection and economic interests, and their programs are not open source

extended data

in 2018, a large number of new DAPP projects were launched. According to the statistics, there are about two or three thousand dapps in the whole network. According to the DAPP survey of fluence labs, 72% of DAPP projects were launched in 2018. This means that in the past year, the number of dapps in the whole network has more than tripled

of all dapps, more than 80% are developed on Ethereum, about 20% on EOS and less than 10% on Tron. It is worth noting that about 10% of the projects are developed on multiple main chains at the same time, while the number of dapps developed on other main chains is relatively rare

there are about ten projects based on gxchain, mainly small applications in block city

4. Do you want to learn blockchain development technology or just want to know what blockchain is? If it is the former, you can look at the code of other blockchain projects and learn about it first. If it is the latter, we can pay attention to some good blockchain we media. Blockchain is an emerging instry. There is no ready-made training course. It depends on self exploration and understanding.

5.

Public chain, also known as "public chain", refers to the blockchain that anyone in the world can enter the system at any time to read data, send confirmatory transactions and compete for bookkeeping. The public chain is generally considered to be "completely decentralized", because no indivial or institution can control or tamper with the reading and writing of data in it. In terms of application, blockchain public chain mainly includes bitcoin, Ethereum, super ledger, most counterfeit currencies and smart contracts. The ancestor of blockchain public chain is bitcoin blockchain, which has the following characteristics:

1, open source code

upload the code to GitHub, and everyone can get complete blockchain data by downloading, Accept the test of the public

2, complete decentralization

anyone can become a node, each node is open, everyone can participate in the calculation of the blockchain, any node is not permanent, but phased, and any center is not mandatory for nodes. Anyone can read and send transactions, and transactions can be effectively confirmed on the blockchain. Anyone can participate in the consensus process. The consensus process determines whether a block can be added to the blockchain and the exact current state. Everyone can get financial reward from it, which is proportional to their contribution to the consensus process. These public chains are generally considered to be "completely decentralized"

3. Developing decentralized applications

through this public chain, developers can easily develop centralized applications. Public chain can protect the rights and interests of users from the influence of program developers

6. Only the circulation of digital currency can proce value. The DGC is the only one to promote the circulation first and then. DGC is a kind of digital cryptocurrency, which has two characteristics: decentralization and open source code. Just like 100 yuan RMB, each money has a different code. A total of 500 million shared coins were mined, each with a different code. The shared currency is gram

7.

1. Learning conditions:

level above 45, each player can only learn two life skills at the same time. If you reach level 90, you should be able to learn the third life skill

8. Blockchain is just hot. Just like bike sharing, only the elite can survive after the limelight. If you are an elite, you will have a future

9. Only after using it can we know whether it's good or not. We can't believe that the advertisements are very good. In fact, they are average

10. This can't be generalized! Some Chinese medicine is very reliable, where he is, you can find him (her)! Not necessarily the hospital of traditional Chinese medicine or the people's hospital!