Apologies first English is not my native language.

I want to work with hyperledger for a bunch of IoT devices.

People owning the IoT devices need to be able to make transactions (with the data).

My question is, do the IoT devices need to work as nodes? As in, have all the ledger data?

Or is there a way for the ledgers to be outside of these devices?

If so, How do you authenticate that the data belongs to the specific IoT devices?

How do people make transactions claiming the device belongs to them?

As far as I understand, mining works like this.

They get the "data" from the pool, in in order to verify them and put them in a "block",

they try to find the nonce with which if hashed with the data and the previous hash data produces

the hash result that starts with 0000000000xxxxxx...xxx.

What I don't understand is, what is this "pool" where they send the data to all the nodes? Also, how do the nodes

verify the integrity?

What if the pool is compromised and sends the wrong data in the first place?

How is finding the right nonce alone guarantee the integrity of data and transactions ?

I would very appreciate if anyone could explain please.

Thank you.

For example, from what I understand,
If Alice and Bob share an Bitcoin Account that holds 500 Bitcoin.

Alice could spend all 500 bitcoins on a car in North America when Bob spends it on a different car
in Asia. Both transactions would go to "pool" to be processed. Both of them would be processed in the next block.

What I don't understand is, 1) Would the transaction be visible on explorer site ? Both of them ?

2) I get that maybe a few blocks later, the longest chain would be taken and one of the transactions
would be revoked. But how is this reliable at all? The two cars are probably in possession of Alice and Bob already.

The seller needs to wait at least 4 blocks after the transaction is complete?
Also, regarding the 1st question, what happens on the explorer when the longest chain is taken ?
Before longest chain is picked, which one is displayed?

I am very confused with this. I would really appreciate a reply. Thank you very much in advance.

Apologies first English is not my first language.

I have a CS degree, and I've done a few ERC20 codes out of interest.

I also have BASIC knowledge of cryptocurrency.

I want to build platform like ethereum, or EOS (I know the latter hasn't made one yet).

Right now I have no real knolwedge (except for things you can find easily on google).

I really want to learn, but I don't know how.

I live in Korea and I can't seem to find a good course here. Could anyone recommend a course?

It can cost $$$. I found one on https://blockgeeks.com/pick-your-plan/ but don't know if it's worth the money.

I would really appreciate a reply. Thank you very much.

Hello, apologies first, English is not my first language.
We want to raise ethereums for our project (ICO).
We want it to make individual address for every single person who registers on the website

so that we can know who sent the ethereum when we get them.
If address XXX is assigned to person A, and if we get eth in that address,
we would know that A sent eths.

Could anyone tell me how one does this please?
Any reference? How can one manage a LARGE number of wallet addresses?

apologies first as English is not my first language.

I would really appreciate if anyone could explain the concept of hardfork.

As I understand it, if there is a hardfork with say, bitcoin, everyone who own X amount of

bitcoin gets X amount of hardforked coin as well.

For example, if bitcoin platinum were real, a person who owns 15 bitcoins would've got

15 bitcoin platinums.

But, software engineers who hardforked ended up with tons of them.

For example, litecoin developers ended up with tons of litecoin.

How did this happen? Also, how can I study about the blockchain technology?

And if one hardforks a coin, how do you acquire the mainnet (the network)?