https://www.bilibili.com/video/av45247943
If there are four ABCD bits currency trading, wherein the transaction A to B by 10 bits credits (BTC), and this information to be broadcast to all other traders know.
We hypothesized that this transaction has been performed, and a block chain "block" about 4,000 such transaction information (billing), a size of approximately 1M.
This bill will do its packaging, packaged as a block. (Why go pack, who will pack?), Because the chain to the center of the block, not as a unified management center as the National Bank, in order to obtain the right package, there will be an "algorithm problem" appears, which traders cracked the problem, they acquired the rights package, and get a bit of coin design awards (ie bitcoin), commonly known as "mining the success of" the. so miners (traders) to mining (earned BTC) is the source of the packaging system of incentives and traders the right to deduct acquisition fee.
1. Who shall prevail? (Broadcast network delay caused by each trader receives the order may not be the same, in order to record who is the subject block it?)
Nakamoto proposed workload proof (mining), each participating user must do a difficult math problem, this is difficult math problems do you put it out, it won the right to package.
You got into the package, you will get commission and bonus package.
2. Why accounting? (Why do you broadcast to me, I would receive yet, so how can I use their computing resources (computers, GPU, mining machine) to record a nothing to do with my account of it?)
Accounting Award:
(1) fee income. A paid to B, 10 bits coins, 10 to spend some extra fees paid for packagers to.
. (2) The packaged bonus Satoshi design package provides 50 bits of reward currency, and every four half, i.e. the total number of bits of coins:
50 × 6 (6 an hour 10 minutes, 10 minutes as packaged) × 24 hours × 365 days × 4 years × (1 + 1/2 + (1/2) second power + (1/2 ) + ........ third power (because halved)) ≈ 2100 bits coins Wan
3. How do security? (Block trading information to prevent tampering)
4. How to prevent double payment?
5. How secret? (The information is public, people will know how much money you yet?)
6. To demonstrate how the workload?
之所以需要矿机或者上万台的专业挖矿机去计算这个算法问题,是因为这个问题与密码破解是有一样的难度的,我也在想这是不是也有可能是有一部分黑客在挖矿的过程中,
同时利用这样的矿机进行了密码暴力破解同时制造了比特币勒索病毒.
(李永乐):假设求解的问题为某字符串解释为sha256后,规定的其前面的二进制的数位为0000000111,要确定每位去碰撞到那个数值,概率均为1/2,那么难度总系数为(1/2)^n.
(中本聪):需要每10分钟出一个块,怎么去保证呢,就是调整李永乐说的调整n的难度.让接入区块链的计算能力与n实现与规定时间的均衡.
假设世界上有1万台矿机,每个矿机的运算能力在14T/s,(即1秒钟执行14T次哈希运算),1T是10的12次方,即1.4×10^13/s
10分钟出现一个区块(根据中本聪设计), 10分钟为 600秒
计算次数 1.4×10^13(每台矿机1秒的计算能力) × 600s(10分钟,区块出现世界) × 10^4 (1万台矿机) = 8×10^19次 (假设全世界1万台矿机,在这个10分钟里计算的次数)
根据设定10分钟内"打包权利的计算题"的难度n,来调整总计算量与求解出的时间配置.