The biggest problem block chain platform, you can use a simple analogy to illustrate:
The twenty-first century, the Internet speed is very slow. At that time if you have a blog, users want to access both time consuming and costly. People are aware of this issue, but also recognized the usefulness of the Internet.
To solve this problem, many efforts to improve the infrastructure and the design of the Internet. At the same time, it is also built from the Internet facilities more powerful hardware to run.
Because of these improvements, faster Internet access costs become lower. Previously, developers were only able to create a single Web page. But now, developers can build sites like Facebook, Google and Twitter on the improvement of infrastructure. All of this is possible because the Internet speed and capacity has been greatly improved.
Block chain technology is also facing a similar problem - slow and costly.
Many companies are committed to building block chain infrastructure can be expanded, so that the block chain platform in the future become mainstream. Once that day comes, people can not only use the block chain to make payments, you can build applications similar to Google and Facebook on top of it.
1, block chain and expansion of capacity issues
Before explaining the expansion issue, we must first explain the concept of throughput. Suppose you in the car such as the railway station, the train every one hour apart, can only do 10 people. Once the train is full, the tenth one passenger can only wait for the next trip. With this analogy, the passengers on behalf of the transaction, bitcoin or Ethernet Square block chain such common platform can handle an average of about 10 transactions per second.
By contrast, such as VISA payment company is currently averaging 5,000 to 8,000 transactions per second. Throughput rate is called task processing. Compared with Visa and other payment platform, block chain platform is very low throughput.
Now suppose you are in the same train station, but this time there is another one hundred people want to ride this train. The train came, the conductor looked at the crowd and said:. "Can pay up to 10 people on the train," because you are in a hurry, so you'll pay a lot of money to buy a ticket on the train.
Due to the low throughput block chain platform, transaction costs continue to rise. For example, a $ 10 deal is likely to be required to pay a $ 2 transaction fee on a crowded block chain platform. Therefore, slow and high costs are a huge obstacle to the mainstream transaction block chain migration to the platform on the Internet.
2, to enhance the capacity expansion
In order to improve the mainstream acceptance of the block chain platform, these platforms require expansion. To this end block chain companies have proposed several solutions.
2.1 increase in block size
The first most direct way is to increase the block size. Back to the train analogy, this means that the train will increase capacity from 20 people to 10 people. In this way, the train can transport more passengers within a specific time, reduce congestion station.
The current block size bits credits 1MB, the processing up to 2MB per second can be doubled it. The larger the block, the higher the amount of processing per second.
But in practice, there is a problem, you will assume a block size from 1MB to 1GB, when you create a block, it must be transferred to others in the network, and the network can not handle large files quickly.
As you use e-mail, when you upload a large file, mail will not be accepted. This is to increase the wrong block size can not exceed a certain critical point, so the ability of this solution is limited.
2.2 Chain Solutions
The second possibility is a chain solutions, such as lightning Bitcoin network, Ethernet network Square lightning, the body and the Neo network.
In the current case, each time transaction processing, all must be verified for each node in the network. (Node is a computer running algorithms and processing transactions)
For example, you want to buy a cup of coffee every day in the month from a particular coffee shop, coffee price is $ 1, but in the online trading $ 1 a day is very expensive and you do not want to $ 1 the entire transaction and crowded The internet. So you and cafe owners signed a contract.
The contract, you have to pay $ 1 a day symbolizes through license fees as coffee. You send to the network a deal to mark the beginning of the contract, 30 days after sending a deal to mark the end of the contract, after the end of the contract, the cafe owner can put 30 through certificate exchange is $ 30 on the network.
Because these are private agreements occurring outside the block chain network, they are called the lower chain solutions. The disadvantage of this trading system is that the entire process is focused on server transactions under the trusteeship of these chains, these chains Network is a black box, its transparency and safety is doubtful.
2.3 Proxy consensus agreement
Currently processing speed on the block chain network is very slow, as each node in the network must be involved in the processing. If there are a thousand nodes in the network, then one thousand nodes must be involved in each transaction processing network.
If a community has 1,000 people, everyone must agree on the process not only long, but also very confusing. Conversely, if you choose 10 representatives from the community, they appointed the administrator of the community, so that 10 people vote, consensus will be faster and easier.
Similarly, you can entrust a group of nodes to run the protocol and agree on a transaction, the consensus proxy nodes will represent the consensus of the community.
Most can block chain expansion projects are using this protocol. In order to enter the league of governance, community members must be registered interest and pass the test (called equity certificate or proof of authority). If they are successful, they will be granted warrants to join the League of governance and run a consensus agreement.
2.4 Segmentation
Segmentation is a chain of divide the network into the expansion program into pieces, but the concept is not new slice database field. Segmentation the large database into smaller, faster, more manageable components, called data fragmentation.
To show how it works, and now you have a hypothetical question consists of five steps.
Imagine that you have 10 students can help you this question, and this question five parallel steps can be divided into a classroom. So you put the class into five groups of two, each child solve a task.
Once the group has completed its subtasks, you will carry a message to the teacher, the teacher will answer summary of all five groups, and pass the complete answer to all groups. In this way, even when the teams to focus on their sub-tasks, you do not know what other groups are doing, but in the end all the participants will get an answer.
In this case, the student is a node on the network. Class is the network in all nodes, and the Panel is fragmented. The teacher represents the Directory Service Commission (DS), which itself is a fragment.
If the Bitcoin network compared to a classroom, the students must solve their own problems every step, which takes a much longer time, and the burden of each participant should be much greater.
However, using the network Segmentation, if you have 10,000 nodes, the certification process by the workload, they were randomly divided into 10 groups, each group is called a slice. Each fragment handling a different set of data and draw within the group agreed to answer.
Then, each slice will submit a summary report of these data to a slice called Directory Services Commission, which it has to co-ordinate data summary of different fragments and combine them to form a larger data set, called the final block, the final block of data will be returned all the fragments.
Can be seen from the above analysis, slicing technology is a decentralized, secure the expansion program chain, a linear expansion capacity - in other words, the more nodes, to give greater throughput.
Segmentation of two types: the state network fragmentation and slicing, Ethernet technology is being developed state Square slice. Difference between the two techniques is that slice, not every network node must handle each piece of information, but each node must store additional network information fragment;
If slice status, each node only stores the processed their own subset information, although this reduces the burden on each node, but the exchange between the fragments may become complicated.
3, slicing drawback is the complexity of design and deployment
Deploy a simple version of the patch is easy, but to correct and safe operation difficult, which is why it is now very little research team. Compared with the simplest solutions to increase capacity simply adjust a parameter block - the block size and throughput increases. But when introduced slicing technique, things need to be considered very much.
How to properly divide members of the group? How to assign tasks? All these have brought the system complexity. But if done correctly, the system will be distributed, secure, and has a linear expansion capability.
4, bandwidth and storage capacity expansion scheme is a common problem for all
For Bitcoin and Ethernet Square, these blocks chain platform, this problem is not serious, because they are low throughput. Bitcoin Ethernet Square and 10 transactions per second, at the current rate, all transaction data within a year will reach several GB.
However, when we deal with hundreds of millions of transactions every day, the data will be overflowing. To store all this data, we must find better storage solutions, this is not a network fragmentation can be directly addressed.