today I want to present schema of something named Proof of Work.
There are people which better understand situation with pictures then with words. Also there is a saying one picture is worthy thousands of words.
First of all, imagine, that all blockchain is 6 computers. All of them of course connected. For example like on the picture:
Computer 5 is in another colour for a reason. Read next part and you'll get why.
Next think, imagine, that we have in blockchain 4 elements. Like this:
And of course, task. It is needed to add one more chain: blockchain5 to all of this. Here is what will happen:
- It's not possible just to add blockchain5 via simple copy in memory of all 6 nodes.
- In order to add new chain, some computationally hard puzzle should be solved.
- Suppose that computer 5 solved that puzzle
- In that case other computers ( i.e. 1, 2, 3 ) will validate result. NB validation is not computationally intensive
- After 51% of computers or more agree that solution is correct then new blockchain element will be added to list
- Computer 5 will get a reward