General Block Chain questions / Js Block Chain

Question

First of all. I'm very new to block chain technology so please forgive any noob questions.

So I'm going a lot on the following tutorial on youtube regarding the knowledge that I do have other than general block chain theory that I've learnt over the past week.

https://www.youtube.com/watch?v=zVqczFZr124

1. People say that it isn't possible to shut down the block chain but the more that I look into the subject it doesn't matter how much tech you have behind your block chain there has to be an entry point I.E to the master node with a dedicated I.P address. If this is the case then how is it not possible to shut it down? Wouldn't it be a simple fact of blocking the ip like it has been done for so long in other countries?
2. Proof Of Work: I get that there has to be some sort of way of proving the source of information came from a certain contributing node. However I'm not totally understanding the point of the POW. For eg, if there was 100 block nodes connected to various master nodes then the information that would be processed by each node would be then emitted by each node to the master nodes which would then process the master nodes for insertion into the ledger, correct??? If that is the case then what is the point of the POW/High powered computer specs etc?? isn't it just using up computer resources with the algorithm??? isn't there nay other more efficient way to do this. It sound like a job that any average computer could do in this day and age without having to max out the CPU etc. This is just something that I'm not understanding.
3. Proof of Steak and Proof of Minimum: I'm quite confused with this type of mining. I get that they say "Ok, well we want you to hold on to your tokens for a long time and then we'll reward you with coins (Mining)", But for instance if I said that I want all my customers to believe in the tooth fairy and paste it in their social profiles on my block chain based network and that is the type of mining we choose, then how does this help with the actual job at hand ??? I.E the POW method is one way to prove that they did a job etc but thats the point. There is a job to do. I don't get how POS/POM takes care of this.
4. Supposing that the above questions have been answered then I'm looking in to different way that I could do a different type of block chain. More like a proof of participation. Simply being a relay point of information, then I'm seeing issues.
   If I did master nodes to store all the information in the ledger and insertions etc then then the information has to pass this point of entry first and then relayed to the block nodes, correct?

Presuming I'm understanding things correctly etc then can anyone point me in the right direction of how to implement the two methods above to the block chain in the tutorial?
Last question is I don't see many articles or people suggesting javascript for a block chain. I personally can't really see any issues with it. As far as I can see this is more of a theory implementation that could be pretty much implemented in any language. But if I'm understanding that wrong then I would really appreciate feed back.

Thank you.

Answer 1

People say that it isn't possible to shut down the block chain but the more that I look into the subject it doesn't matter how much tech you have behind your block chain there has to be an entry point I.E to the master node with a dedicated I.P address. If this is the case then how is it not possible to shut it down? Wouldn't it be a simple fact of blocking the ip like it has been done for so long in other countries?

That is completely incorrect. There is no master node nor is there any central source that dictates what the blockchain is. The blockchain is distributed to all nodes, and all nodes update their local copy of the blockchain according to the consensus rules that the node is following. If everyone is following the same consensus rules, then everyone will converge onto the using the same blockchain. However, there are some circumstances where a node will not use the same blockchain as all other nodes, but these only happen when the node is under attack.

Proof Of Work: I get that there has to be some sort of way of proving the source of information came from a certain contributing node. However I'm not totally understanding the point of the POW. For eg, if there was 100 block nodes connected to various master nodes then the information that would be processed by each node would be then emitted by each node to the master nodes which would then process the master nodes for insertion into the ledger, correct??? If that is the case then what is the point of the POW/High powered computer specs etc?? isn't it just using up computer resources with the algorithm??? isn't there nay other more efficient way to do this. It sound like a job that any average computer could do in this day and age without having to max out the CPU etc. This is just something that I'm not understanding.

Again, there is no master node that inserts things into the blockchain.

The proof of work is something that is done by miners to show that a certain amount of work was done to produce this block. This secures the blockchain because nodes will use a blockchain which has the most proof of work and is valid under its other consensus rules. This means that if an attacker wished to defraud someone by convincing their node that a different blockchain were the real blockchain, then they would have to do the same amount of work that has been done on the real blockchain. At that point, it would be far more cost effective to simply be an actual miner instead of maliciously attacking someone as the cost of doing that much work is very high.