I've been thinking about item 2. on the i0coin client upgrade bounty.
2. OP_RETURN must be set to 80 bytes (to allow financial platform development)
I think it may be best to keep OP_RETURN at 40 bytes like Bitcoin. There are a few reasons for my change of mind. First, financial platforms are working fine on Bitcoin using 40 bytes. Second, it reduces the number of differences, even if minor, between i0coin and Bitcoin so there are less chances for bugs. Third, i0coin has a 90 second block time compared to Bitcoin's 10 minutes, so i0coin's block chain is growing faster. I0coin's block chain is already over 11 GB even with small numbers of transactions. I'm worried that a larger OP_RETURN could balloon the block chain even more. Of course, if and when Bitcoin updates the OP_RETURN byte size, so will i0coin.
Feedback is welcome.
2. OP_RETURN must be set to 80 bytes (to allow financial platform development)
I think it may be best to keep OP_RETURN at 40 bytes like Bitcoin. There are a few reasons for my change of mind. First, financial platforms are working fine on Bitcoin using 40 bytes. Second, it reduces the number of differences, even if minor, between i0coin and Bitcoin so there are less chances for bugs. Third, i0coin has a 90 second block time compared to Bitcoin's 10 minutes, so i0coin's block chain is growing faster. I0coin's block chain is already over 11 GB even with small numbers of transactions. I'm worried that a larger OP_RETURN could balloon the block chain even more. Of course, if and when Bitcoin updates the OP_RETURN byte size, so will i0coin.
Feedback is welcome.
Bitcoin 0.11.0 has enabled block chain pruning. If we upgrade i0coin to 0.11.0 then we could use larger OP_RETURN byte sizes.
Read about block file pruning here.
https://bitcoin.org/en/release/v0.11.0
Pruning definitely helps for those who can do it, but i0coin will need to maintain some nodes with full block chains. So I would still prefer to keep the block chain as small as possible with OP_RETURN at 40 bytes.
I do like the idea of pruning. It may attract users who don't like large block chains taking up room on their hard drives. I'd be ok with changing the bounty instructions to require version 0.11.0.
I've been playing with pruning on Bitcoin 0.11.0. It does reduce the Bitcoin folder from 46 GB to about 1.5 GB, but it's not much use in this mode. You CANNOT run a wallet, which means you can't send or receive coins. (A future release will provide wallets with pruning enabled.)
The main use I can see for running a client with pruning enabled is to create a "lite" node which can relay transactions and the latests block data. You can also mine using pruning, but there are potential cons to doing this.
"...550 blocks is not exactly a major buffer to prevent a potential Bitcoin fork. And if the majority of mining pools end up on on a fork of the network for a lengthy period of time, all hell will break loose."
https://www.bitcoin.com/news/pros-and-cons-on-bitcoin-block-pruning/
I can see this may help i0coin down the road to create more "lite" nodes to expand the network, but I'm not so sure this is a big advantage at this time until we can run a wallet too.
