bitcoin is decided by port and algorithm?

[myapple]

I tested the bitcoin wallet. I changed the name of the coin but I keep
1 I keep the port 8333 and 8332
2 I keep sha256d algorithm
3 I keep using the same genesis hash
And
I change the bitcoin name and the max_money

i found the the coin I mined was dropped and it will also follow the long Blockchain

Does that means
Once the algorithm and port and genesis hash was decided， the coin will merge even i changed the coin name etc?

[1713473063]

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[1713473063]

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[1713473063]

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[1713473063]

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[achow101]

I tested the bitcoin wallet. I changed the name of the coin but I keep
1 I keep the port 8333 and 8332
2 I keep sha256d algorithm
3 I keep using the same genesis hash
And
I change the bitcoin name and the max_money

i found the the coin I mined was dropped and it will also follow the long Blockchain

Does that means
Once the algorithm and port and genesis hash was decided， the coin will merge even i changed the coin name etc?

Yes. The name is completely cosmetic; there is no name in the Bitcoin blockchain that identifies it as being Bitcoin. The thing that identifies it as being Bitcoin are the consensus rules. This DOES NOT include the port, but it includes the mining algorithm, the genesis block, the difficulty adjustment algorithm, etc. If you do not change any of the consensus rules, then you are using Bitcoin.

[myapple]

Thanks
Whether it also includes the number of coins generated in each block and the block size
？I mean the parameter nBlockSize

[myapple]

Continue from last post
As I understand a new coin based on the same genesis block of bitcoin must have some feature to make itself rejected and not merged by bitcoin due to the long Blockchain of bitcoin
1 to change port, maybe the bitcoin wallet can forward from 8333 to a different port which will easily merge the new coin due to its longer Blockchain?
2 to increase block size, if there is not much transactions the real size will be very small, this will not make much difference
3 decrease the maturity for mining. Will this helpful to made the coin independent from bitcoin?
4 change the number of mined coins in each block?
5 if in one block I make many transactions to let the size of the block more than 1000, as I know this block will be rejected by bitcoin but acceptable by the modified coin, so after this coin，the new created coin will be independent from bitcoin and will not merge with bitcoin due to the longer bitcoin’s Blockchain

Thanks

[ranochigo]

1 to change port, maybe the bitcoin wallet can forward from 8333 to a different port which will easily merge the new coin due to its longer Blockchain?

The problem with it is that the reference client DOES connect to nodes with non-standard ports, albeit rarely. If that happens, your whole network is gone,

2 to increase block size, if there is not much transactions the real size will be very small, this will not make much difference

Yes.

3 decrease the maturity for mining. Will this helpful to made the coin independent from bitcoin?

Yes but read the last point.

4 change the number of mined coins in each block?

Yes but read the last point.

5 if in one block I make many transactions to let the size of the block more than 1000, as I know this block will be rejected by bitcoin but acceptable by the modified coin, so after this coin，the new created coin will be independent from bitcoin and will not merge with bitcoin due to the longer bitcoin’s Blockchain

Yes. The reference client only considers the longest valid chain with the longest proof of work. Since your block violates the protocol rule for the block weight, Bitcoin reference nodes will not accept it.

However, your modified coin node's would consider the Bitcoin chain as valid, since the smaller block size does not technically violate any rules for your modified client.

The reference client considers any block reward (without transaction fee) below the current 12.5BTC as valid so Bitcoin can still take over your own Blockchain. You have to somehow modify the blocks being produced such that the blocks are only valid on your modified coin (ie. decrease the block reward).

[myapple]

Thanks a lot
If I set the fourth and fifth Blockchain will yield 0 coin and other blockchains yield 12.5 coins, whether all the bitcoin blockchain will be rejected from my coin after the fourth blockchain even with the same algorithm and port
In this way my coin will be independent?
Thanks

[myapple]

For the bitcoin source code. If I change from 10 minutes one block to 5 minutes one block and also I changed the port, whether I still face th possibility that my new coin will be merged with bitcoin due to the longer blockchain?

[achow101]

For the bitcoin source code. If I change from 10 minutes one block to 5 minutes one block and also I changed the port, whether I still face th possibility that my new coin will be merged with bitcoin due to the longer blockchain?

Changing the difficulty adjustment calculation to target 5 minutes should make it not be wiped out after the first 2016 blocks. The first 2016 blocks can still be the same as Bitcoin's and could wipeout your chain.

[myapple]

thanks
why the first 2016 blocks different？

[achow101]

thanks
why the first 2016 blocks different？

Because the difficulty adjustment algorithm won't kick in until after the first 2016 blocks, so only after the first interval will your blockchain be different. If you change the retarget period, it will be the minimum of 2016 blocks and whatever you set the retarget period to be, i.e. if the retarget period is smaller than 2016, it will be that. Otherwise it will be 2016 blocks.

[myapple]

thanks
so if i set it to be smaller than 2016, for example set it to be 100, I will not eat my coin after the first 100 blocks?

 Thanks

[achow101]

so if i set it to be smaller than 2016, for example set it to be 100, I will not eat my coin after the first 100 blocks?

Not necessarily. You may need to increase what the maximum target value is (i.e. decrease minimum difficulty) if you are also changing the target interval time between blocks.

[myapple]

maximum target value is which parameter? How to increase it for example

[achow101]

maximum target value is which parameter? How to increase it for example

That's the powlimit variable found here: https://github.com/bitcoin/bitcoin/blob/master/src/chainparams.cpp#L83. To increase it, just make the number bigger.