There has never been a lack of professional technical vocabulary in the blockchain field, such as asymmetric encryption technology, fragmentation technology, DAG technology...It can be said that if you don't understand some technology, you can't even understand the white paper. Today, the Intelligence Bureau will introduce a new blockchain technology-DAG technology
1. Reasons
We all know that the underlying public chain is the foundation for the implementation of blockchain technology. Only when the public chain technology is mature can blockchain applications enter millions of households. But for a long time, the public chain has always had problems such as slow processing speed, high cost, and potential safety hazards. If there is no safe, reliable and efficient public chain, the development of the entire blockchain industry will be severely restricted.
In this context, DAG technology came into being and was used to solve various problems on the public chain.
Second, what is DAG technology?
DAG is a directed acyclic graph. It is a distributed ledger technology that is different from mainstream blockchains. It upgrades synchronous accounting to asynchronous accounting. Many people think that it can solve the high concurrency problem of traditional blockchains. A revolution in blockchain from capacity to speed.
With DAG as the network foundation, the limitations of the blockchain are solved. This allows the blockchain to expand infinitely at a tiny cost. The payment process can be completed very quickly. However, only a small portion of cryptocurrencies are currently using the next-generation DAG architecture.
Three, the characteristics of DAG technology
Compared with the current public chain technology, DAG is actually the difference between a graph and a chain. For a chain, it cannot handle only one part, because the chain has only one in-degree and out-degree, and the nodes on the chain cannot be divided into several Nodes to process, but for graphs, because graphs can have multiple out-degrees, then multiple out-degree connected nodes can be processed at the same time. Therefore, its characteristics are:
1. Transaction speed block, local processing and parallel settlement realized by DAG can greatly increase transaction speed.
2. Strong scalability, because each node can calculate without waiting to synchronize the data of other nodes, making it easy for the accounting node to reply and extend, so DAG is very suitable for IoT projects, such as machine micropayments.
3. It is more difficult to do evil. Compared with the chain structure, the difficulty of malicious modification in DAG is much greater, because DAG has a lot of out and in degrees. If a node is to be modified, the corresponding in and out degrees are all To be modified.
For the chain network, it is not that the processing power of the nodes is not strong, but the chain structure cannot be calculated in parallel. The time wasted is actually waiting time: one is to initiate a transaction, and the transaction needs to be synchronized to all nodes, and the other is when there is one The node confirms and needs to synchronize to the entire network.
For DAG, there is no such problem. When the wallet initiates a transaction, it does not need to wait for how many transactions it has before. It only needs to undergo partial verification, network-wide broadcasting, and other partial verification, which is equivalent to decentralizing transaction confirmation. Nodes are doing work similar to a puzzle, splicing their own and other confirmed transactions.
Fourth, the status quo of DAG technology
The representative projects using DAG technology, the most well-known is undoubtedly the DAG three carriages-IOTA, Byteball, Nano, as the latest distributed ledger competition technology, DAG began to attract a lot of attention began when IOTA rushed into the market value in the second half of 2017 The currency ranked fourth in the rankings, and new projects based on DAG continue to enter people's vision.
DAG is undergoing rapid development and innovation. In addition to the troika, new DAG projects have made updated progress in consensus algorithms, decentralization mechanisms, speed and concurrency. Recently, projects that have attracted attention include HashGraph. , Algorand, Nerthus, Mixin, etc. For specific introduction, please Google or Baidu by yourself.
In addition, each project that uses DAG has certain differences. For example, the structure used by IOTA is called "tangle", and Byteball uses "witness"... As more and more people and projects participate in the ecological development of DAG In recent years, the possibility of DAG application is also increasing.
Five, summary
DAG is a new generation of blockchain technology facing the future. With its popularity, developers have gradually increased. The advantages of the DAG project are gradually becoming prominent. Its superior performance and strong scalability have a huge impact on existing blockchain projects. From a technical point of view, DAG has brought us a new blockchain experiment.
Everything has advantages and disadvantages. DAG has fast speed and high throughput, but as a very young data structure, security and consistency need more verification and recognition, and the application scenarios are not as extensive as traditional blockchains; However, the advantages and innovation speed of DAG technology have emerged, and more and more subsequent innovation projects based on DAG and DAPP are emerging rapidly.