Are there sidechains in NEM to make micropayments?
Is it possible to create a public “Catapult” blockchain without fees as a sidechain of Mainnet NEM?
The short answer is no, the longer answer is 'ish.
You can run as many Catapult chains as you wan’t but they’ll be seperate networks. You can adapt the code however you want and remove fees (presumably the private version doesn’t bother with fees) but those are in place for a reason (regardless of what Nano folks would have you believe).
Youl could do x-chain-tx from your chain to the mainnet which doesn’t make it a side-chain but you did get what you wanted to have and you can switch to xem from whatever your chain uses as token (assuming anyone on mainnet is willing to exchange xem for your token).
And would it be possible to connect Catapult (NEM v2) with mainnet (NEM v1) and make Catapult public ?
As far as I know, this catapult sidechain would have only 1 node, so technically is not a sidechain.
Any other solution?
No, there is no x-chain-tx in nem before Catapult.
How would we change this ?
I propose to change the fees for NEM to nearly 0 for amounts < 0.05 xems
We hace 6 decimals -> so if tx amount is <0.05 xem -> fee = 0.000001 xem
How would I propose this? Is there a procedure? Like EIP in Ethereum
How would you block spam with such low fees?
Also NEM is not designed to be a digital cash with micropayments.
In the case of Bitcoin, there are solutions on the table, like channels, but they are solutions off-chain and without great support yet.
Now I see that both are separate matters; sidechains are one thing and micropayments are another.
And moreover, what would be the motivation for the harvesters if the fees were towards 0?
None of them would “mine” that transactions.
Or should be enforced to mine 90% tx with fees, and 10% with ~0 xem?
Too much work to do, and the dev team may be occupied in other priorities like deliver Catapult on mainnet.
It might be a difficult NIP (NEM Improvement Proposal).
Good point, but do you know if that NIP procedure exists?