One more question: When I use Exodus to store my coins, I have my private keys, so I am the only person who has access to the coindatas in the blockchain. Is my wallet on exodus a node. Do I run a node by using my wallet on exodus?
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Well the blockstream satellite can only receive new blocks, so you would still need some internet connection to send the blocks to the network, you can use another commercial satellite transmitter like BGAN for that if you want to go completely off wire 
In practice it would be quite difficult to actually replace the transmission layer in Bitcoin you would have to get a bit innovative, but it is possible.
I’m not familiar with Exodus wallet, but I’m guessing its just a light node or SPV.
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HI, can only the miner that solves the block add an unconfirmed transaction to the BTC blockchain?
Yes, when a transaction is mined in the block, that means one confirmation of the transaction and each subsequent block means another confirmation
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So only the miner that is awarded the block confirms the transaction? Dose this mean every transaction has to be confirmed in order for a block to be awarded? Is the fee/gas payed only to the miner that is awarded the block?
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A block is a confirmation. Every transaction once put in a block is confirmed.
Not sure what you mean by that. Once a transaction is in a block its confirmed.
Yes, fees are only awarded to the miner that mines a block but there is no notion of gas in Bitcoin. Gas is used in Ethereum for execution of code inside the EVM. How the block rewards are distributed however is a bit more complicated since you can have forks (or so called uncles) in Ethereum and the rewards are distributed also to the miners that mined that block. A good explanation of this can be found in recent tweets by Andreas:
Its a bit of a long rant, but worth the read
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hi guys,
great community
quick question
if a have bitcoin in my wallet and i send half of it to someone else
on my wallet it would show each transaction,
how does the blockhain update the block my initial 1 bitcoin was in?
does this not break the chain becuase now ive only got half a bitcoin, and if you change anything in a block it it breaks the hash aswell as the links to other blocks its connected too
thanks
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I am curious how does the Bitcoin source code been protected since it is open and prevent from others to meddle with it?
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It is not updated. The bitcoin is stored in an unspent transaction output (UTXO) and when you want to spend it you use it as an input to a new transaction and the outputs from that transaction can then be sent to multiple addresses (half to your friend and half back to yourself) that become new UTXOs on the blockchain the address owner can use.
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Everyone can meddle with it, that is why so many coins exist. Most of them are forks of Bitcoin, with a few tweaks
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Hi Alko89, thanks for the reply.
So I would think that if anyone should change any of the critical codes e.g. 21M max distribution, bitcoin rewards etc, the community will be alerted and rejected these changes?
What happens if those who are not aware of it (not codes savvy) and update these changes in their computer/node? Is there a group/person that oversees this source code and make sure it is intact? Thanks again.
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A completely silly question.
Can you create fake blocks with fake transactions and try to add that to the blockchain?
What I mean by, if you create a block that has the previous block’s hash, some fake transactions (e.g. transactions sent to my Bitcoin address) and a nonce - and let’s say I manage to get a hash that is lower than the target - where would it get rejected?
And let’s assume that all the senders have enough UTXO to cover those fake transactions.
There is the main repository on Github that has maintainers that merge and review the code from people that try to commit to the core project. So if anyone creates a PR that does is not appropriate to be accepted upstream it will get rejected.
Anyone however is free to fork the project and make changes and start their own currency if they want.
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The transactions would be invalid since they were not signed with the owners private keys. So the entire block would be invalid and rejected by the network.
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Yes, of course, back to first lesson - can’t be a valid transaction as it’s not signed. Thanks for clarifying that.
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Hi Team,
I need some help to understand something,
- a bitcoin wallet holds your private key - OK
- Public key is generated from the private key - OK
- wallet address is generated by the public key - OK
So we need to have the private key to generate the address
So, is a bitcoin wallet and a private key the same thing?
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A wallet stores your private keys. 
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hello all,
just finished bitcoin 101. I think I got it all so far. Some questions I did not see answered
- What is the incentive to be an SPV node which is not a miner? I assume big exchanges with a vested interest in the speed and reliability of the network have an incentive to add SPV nodes to the network but why would any one else run it?
- How does a software wallet on your phone keep the private secure? It appears that using crypto puts a target on your back for any hacker so how can phone wallet be secure?
- I assume that when a wallet gets created the software generates a random private key based on an algorithm of the wallet, but does it also check the (very very unlikely) possibility that the resulting public key and bitcoin address do not already exist?
- in the specific case of a hardware wallet like a nano ledger, how does the address get generated?
thank you for your replies
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generally when you refer to a wallet you refer to a piece of software which
- holds your private keys encrypted and your public key and address
- can query the blockchain to let you know what your current balance is
- can interact with the network to broadcast transactions and receive updates
a “paper” wallet is purely the combination of public and private key
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You would run an SPV node to run your wallet. Did you had a full node in mind? There are usecases for running a full node. You can use it for either development, run your own explorer, connect an SPV to your node, providing you better privacy…
I’m not sure, to be honest I don’t use them 
But I bet they use some kind of encryption to protect the keys from being hacked or just somehow getting “safely backed up” by google.
They don’t, the probability is so low it will basically never happen, except if the software used to generate keys uses a bad RNG. This did happen a while ago I think.
Ledger is a HD (hierarchical deterministic) wallet (described in BIP32). It uses a master key to derive private keys from it.
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