In a distributed database, data is updated consistently, so the process of consensus is performed, and especially in Bitcoin, it takes 10 minutes or more to consensus to counter tampering. Because of this work, if a large number of individual transactions are directly written to the distributed database, the same number of consensus work will occur and the system load will increase. Therefore, we have created a system in which a certain number of individual transactions (transactions) are grouped into blocks, consensus is formed in blocks, and written in a distributed database. In addition, past block information is mixed in the block for tampering prevention, and fee payment information to the maintenance manager of the distributed database is included.
There are various variations of the blockchain in bitcoin era, depending on the settings, such as the presence of the administrator, restrictions on participants, and data reference authority. And some things like bitcoins don’t necessarily need coins (tokens). You can find more info here.
In addition, considering the use of blockchains in financial consortiums, in order to secure security and the ability to respond when problems are discovered, avoiding an open form like Bitcoin, for example, it is possible to narrow down the range of participation by permission type. It may be done. In this case, in terms of the method of determining the updater of the database, mining such as proof of work, which is a competition to eliminate fraud from unspecified majority like Bitcoin, is unnecessary, and reliable participants It is only necessary to determine the data updater by the simplified consensus building mechanism in, and the data update frequency can be significantly increased.
Since there are various variations in the combination of setting items in the blockchain, it often happens that people who are thinking of free Bitcoin type and people who are thinking of closed things with managers do not talk to each other. I am.
Permissioned (also called “closed type” or “private type”), which is often heard in the blockchain classification, is often used in the sense that it has an administrator and the number of participants in the data recording work is limited. .. On the other hand, Permission-less (≈ open type) is often used in the sense that there is no specific administrator and participation in data recording work is freely released.
In any case, when talking about blockchain, it is important to first explain what type you are expecting.
“Shock of blockchain” Supplementary explanation for application to financial services
In the section “Chapter 3 Impact” on “Applications to financial services”, we introduced a basic example of using a blockchain in the financial industry. Here are some ideas I didn’t list.
Use for public offering the biggest advantage of using blockchain for public offering is that ownership of securities can be transferred very easily. By replacing the entire name rewriting layer at the securities settlement organization with the block chain, information transmission and confirmation costs can be greatly reduced.
In this case, if DVP settlement (simultaneous delivery of funds and securities) is not realized, there will be a gap between securities settlement and funds settlement, but even if you do not wait for the blockchain of funds settlement, escrow It is thought that DVP payment can be realized by using the mechanism.
Use for retail international remittances International remittance services using virtual currency, Bitcoin, have also appeared. By using virtual currency, it is possible to “send the value itself” in addition to the remittance information, so there is no need to use bank international remittance, and it is said that the cost reduction effect is great. On the other hand, if the sender and the recipient hold the virtual currency as it is, no intermediary is needed between them, the transaction is completed on a blockchain in a relative (P2P) manner, and the concept of borders is important. There is no need to do so, but this requires that cryptocurrencies become fairly common in both countries.
Currently, it is necessary to exchange virtual currency with legal currency instead of holding it as it is, so it is necessary to exchange cash for virtual currency at the part of the sender and exchange local currency for the virtual currency at the part of the recipient.