I don't pretend to know how sidechains work. However, if they sidechain pegs (or whatever you call them)
require more space than a normal transaction, then why are they touted as a scalability solution?
But they are not. So either you are both unknowledgeable and misinformed or you are straight up disingenuous in your attempt at FUD.
Which is it?
One use case of sidechains is, that you peg Bitcoin to a side chain and then do what ever you want with that values on the sidechain for as long as you like
I don't think, a scenario where you peg Bitcoin to the sidechain, do one transaction on the sidechain and then put the values back in the Bitcoin blockchain makes much sense.
As far as I understand, that is what you are saying. If that is not what you are saying, than just be specific, I really don't want to play a guessing game, about what you are actually talking about.
In your proposal, transactions go to a chain based the addresses involved.We can reasonably assume that different people's wallet will tend to be
distributed uniformly over several sidechains to hold their transactions (if they're not, there is no scaling benefit anyway...). That means that
for an average transaction, you will need a cross-chain transfer in order to get the money to the recipient (as their wallet will usually be
associated to a chain that is different from your own). Either you use an atomic swap (which actually means you end up briefly with coins in the destination chain, and require multiple transactions and a medium delay), or you use the 2way peg transfer mechanism (which is very slow, and reduces the security the recipient has to SPV).
Whatever you do, the result will be that most transactions are:
* Slower (a bit, or a lot, depending on what mechanism you use).
* More complex, with more failure modes.
* Require more and larger transactions (causing a total net extra load on all verifiers together).
And either:
* Less secure (because you rely on a third party to do an atomic swap with,
or because of the 2 way peg transfer mechanism which has SPV security)
* Doesn't offer any scaling benefit (because the recipient needs to fully
validate both his own and the receiver chain).
In short, you have not added any scaling at all, or reduced the security of the system significantly, as well as made it significantly less convenient
to use.
So no, sidechains are not a direct means for solving any of the scaling problems Bitcoin has. What they offer is a mechanism for easier experimentation, so that new technology can be built and tested without needing to introduce a new currency first (with the related speculative and network effect problems). That experimentation could eventually lead us to discover mechanisms for better scaling, or for more scalability/security tradeoffs (see for example the Witness Segregation that Elements Alpha has).
--
Pieter
http://lists.linuxfoundation.org/pipermail/bitcoin-dev/2015-June/008617.html
Lying is just second nature to you, isn't it?
