Bitcoin 2.0: Unleash The Sidechains
techcrunch.com
techcrunch.com
Blockchains have a few serious disadvantages over other protocols (chaumian blinding, or just signed receipts, or a central ledger) -- inefficiency, lack of privacy (zerocoin addresses this, but at the cost of incredibly advanced mathematics), and the 51% attack.
Essentially, anything which is inherently centralized has no business being on a blockchain. This is really anything backed by a physical asset -- the ideas to do colored coins which were gold warehouse receipts were insane/inane. Most of the sidechain proposals I've seen are equally absurd -- the idea of equities issued in a blockchain where the equities are essentially tied to a single real-world issuer is an unnecessary step. You could just have the entity issue digital shares using a centralized protocol; non-repudiation works just as well with signatures. (you might use a distributed system for a virtual corporation of some kind, but that's an exception).
Bitcoin itself makes sense (it's a decentralized store of value), and some of the smart contracts stuff might make sense (but the smart contracts cease being self-enforcing, and thus smart, as soon as a lawyer or government gets involved...), but most of the sidechain proposals involve trying to recreate assets from off the blockchain in a less efficient, less secure way, just to prop up the value of bitcoin itself.
There's no reason to use a smart contract to "prevent issue of too many shares" -- you can just have the market price shares based on what the market believes is the outstanding treasury and float. People can build systems to provide better controls there, which might in some cases involve the blockchain, but it's not essential -- we can price assets using a market with imperfect information already.
A system with ~infinity of distinct issues, traded in realtime on market(s), with perhaps something like bitcoin as a unit of account, makes a lot more sense to me than trying to have one global currency (bitcoin) and then doing things like sidechains (which don't let you escape the limitations of the blockchain protocol).
non-repudiation works just as well with signatures
[1] http://blog.koehntopp.de/uploads/chaum_fiat_naor_ecash.pdf
Yeah, a central ledger works great if you want none of the benefits that Bitcoin offers.
>Essentially, anything which is inherently centralized has no business being on a blockchain. This is really anything backed by a physical asset
Bitcoin has proven that decentralized assets have huge advantage. Your starting assumption is wrong; wealth is not inherently centralized, and assets are not inherently centralized.
IBM shares are essentially centrally controlled by IBM.
Gold (or other physical commodity) backed shares can be centrally issued by each holder of gold; essentially, each bar or vault would have its own issue. This is just negotiable warehouse receipts.
The only classes where decentralized issues make sense are "virtual" currencies like bitcoin, or equities/debts of virtual corporations. There probably isn't a market for more than one virtual currency in the long run, except maybe for sidechains (or exchangeable alternatives) due to purely technical things, or compliance, like zerocash vs. bitcoin.
Why does that mean we have to trade IBM shares with a centralized system? There are huge advantages to having decentralized trading systems.
I still don't think the benefits of this make up for the costs of the blockchain for most uses.
So they can send the dividends to the addresses that own shares. In fact, that should be even cheaper than using a bank or any other middleman-requiring system. Another advantage of decentralization.
I am a bit confused. My impression so far was that something like this would be commonly seen as a decentralized scenario?
I would consider a promise from pg or sama to pay 1oz of gold upon presentation to be pretty low on counterparty risk; I'd consider the same from a random person online who claimed to have gold and be willing to redeem it upon presentation of one of his tokens as a much higher counterparty risk. The market would price these separate issues, and then you could build a basket of gold issues into something meta (maybe with a blockchain, or maybe with smart contracts, to reduce the meta counterparty risky).
In this case, there is no point in representing the asset in a blockchain. The blockchain is probably the least inefficient datastructure we have seen in modern times. A centralised asset is much more efficiently represented by a centralised ledger. You can still use triple-ledger accounting.
This sounds a bit like saying that Bitcoin is inherently centralized because someone can physically hold a gun to your head and compel you to turn over all your coins. I think there are still benefits to a blockchain approach, even if the represented asset is "centralized."
With a signed token (optionally blinded), you get non-repudiability, but if the central exchange is shut down, you don't have safe transfers (it becomes impossible to prevent double spending, so you probably do a single payment to a trustworthy entity and get new tokens from elsewhere). Does nothing for redemption risk.
With blockchains, you have non-repudiability (although less strong than the signed tokens, due to 51% double spend attack being easier than defeating RSA 4096 or whatever), and continue with transferability even in the face of issuer failure, but still have redemption risk (if it's a "backed" currency).
Arguably sidechains give you non-repudiability, eternal transferability, and no redemption risk (at least back to bitcoin). However, it only makes sense for things which are anchored in the root blockchain (i.e. ultimately bitcoin derivatives of some kind); it doesn't make sense for gold bars.
That's true. But gold is a physical asset; shares in a company are not. There is no technical challenge to distributing abstract assets (like shares) over a decentralized system, and there are many advantages to doing so.
Sidechains have issues in the current incarnation that we have been shown; they need to be mined and a 51% attack on Bitcoin will enable the miner to gain access to the coins that are in the Bitcoin blockchain waiting for release via the two way peg.
If these issues cannot be solved then Vitalik may be correct that Ethereum based side chains might actually be a better way as it seems Ethereum is designed to handle this type of advanced contract.
Either way, whatever coin (bitcoin or ether) implements these side chains safely and correctly will likely win as being the foundation for the future of cryptocurrency/platforms.
The side chain idea allows the native cryptocurrency to compete and win out over other competitors. Want faster confirms? Use side chains. Want Zerocash anonymous transactions, peg into Zerocash and peg back out again. I believe the future will be a battle between Bitcoin and Ethereum with a major war zone being sidechains.
Also consider this: If cryptocurrency can have on top of itself many other applications built (decentralised: {web hosting,web app hosting, databases, information, computing engines: {search, math, compute}, contracts, code}) then does that coin itself eventually gain 'intrinsic' value via being the foundation of all these new systems?
Imagine a TOR that is based entirely on the greed incentive and not just good will, where the entire system is an Ethereum contract. Imagine an open source google search where the code is run entirely on top of the nodes and each search costs 1 cent in ether to be paid to the nodes for hosting and running the code.
If this happens, that coin becomes pegged to a brand new internet running on top of blockchains. Just something to think about.
Part of what drives altcoin innovation is the chance for profit (I guess this drives a lot of innovation). Since Bitcoin sidechains are pegged 1-1, there is no chance for a lot of profit on each sidechain. So if you are starting a new altcoin, what are you more likely to do, create a sidechain where you can't make any money or create a separate currency with all kinds of potential?
In fact, much of the same incentive is what is driving the desire to make everything a sidechain. People who are invested in Bitcoin want to keep interest and value there, which is more difficult when altcoins pop up. But why should Bitcoin be the currency, other than it was there first? When you look at some of the PoS coins which are energy efficient and have 10 second blocks compared to Bitcoin's energy-using mining and 10 minute blocks, you have to wonder what would be a better tech going forward (and yes I know about the possibility for attack on PoS coins).
But thankfully, we don't have to put all our eggs in one basket. The current system where multiple exchanges exist where you can go from one coin to another very quickly seems to work pretty well. Does everything need to be pegged to a single currency?
Second, people need to realize that you can't easily decentralize everything using Ethereum (when it exists). Each node will have a relatively small amount of memory and computing power on it in comparison to more centralized servers and will be slower/more expensive for the same reason. So one example people have used are decentralized exchanges. Wouldn't it be nice instead of having centralized exchanges which can be hacked, corrupt, etc (MtGox), just make them a contract on Ethereum? Sure, if you are okay with making each transaction on your decentralized exchange relatively slow and expensive compared to a good centralized exchange.
These kinds of issues will be run into more and more once Ethereum is usable. A lot of things would have seemed like a good fit for decentralization but it is just easier and makes more sense to build a centralized service. Of course Ethereum also will open up a lot of unforeseen avenues as well.
Thing is, sidecoins, Ethereum, etc, don't exist (at least not as a live, fully-functioning implementation). Most writings about either right now are "this is what will be possible", "this is what can happen", the dreaming stage. We need to see these things out in the wild to get past hype to reality.
I believe that apart from Counterparty and ColoredCoins, Ethereum may also be able to run as a decentralized exchange in fact helping Bitcoin and the other Alternative coins.
I assumed a long time ago that eventually many of these coins will somehow tie into each other in the process of building the future foundations of a new decentralised internet. I think that time is coming.
That's not the point. The point is knowing that you won't lose money by trying out altcoins. With sidechains, at any point you can claim back your original bitcoins. You won't be left holding the bag as it happens all the time with separate blockchain altcoins.
Yeah, unless it's 51% attacked in which case you would lose everything.
I see this as a good thing. There are just too many people launching non-innovative altcoins with the only goal of getting rich quick or just for the sake of it. As someone who is mainly interested in the technical side of cryptocurrencies, this will allow me to quickly dismiss any altcoin which is not pegged to Bitcoin as a get rich quick scheme (unless they provide a pretty good technical reason).
Also, there are tons of incentives (apart from speculation) for creating altcoins, I wouldn't worry too much about about sidechains stifling innovation. On the contrary, it will allow people to use new altcoins without the risk of falling into pump and dump schemes.
> But why should Bitcoin be the currency, other than it was there first?
There's no other good reason in my opinion. In an ideal world, Bitcoin itself would have been pegged to an existing currency (e.g. USD) to allow for a more fair initial distribution but this was not possible due to the inherent limitations of fiat currencies. I like the concept of PoS/lower block intervals but as far as I know, those are still open problems (and Bitcoin's protocol could be changed over time to incorporate eventual solutions).
> But thankfully, we don't have to put all our eggs in one basket. The current system where multiple exchanges exist where you can go from one coin to another very quickly seems to work pretty well. Does everything need to be pegged to a single currency?
It works well but it's not a decentralised process which is what sidechains would effectively enable. Of course, some altcoins whose claimed innovation is directly tied to the mining mechanism would still continue to exist independently but this is not the case for most altcoins.
PS: People who believe having a theoretical single Currency would be bad thing usually base their argument on assumptions which do not hold in the cryptocurrency world. In the fiat world, the fact that there are multiple currencies is seen as a good thing because governments can manipulate currencies, restrict or impose their use, etc. Those considerations do not apply to cryptocurrencies. I personally believe that having a single cryptocurrency would be a good thing (I know, taboo!). I'm not sure if Bitcoin will be it though.
Nothing can stop people from falling into fraudulent schemes. Many altcoins are heavily premined, the developers are BS, or the developers have a disproportionately large upside compared to investors. But all of that should be apparent to all onlookers.
The main problem I see with sidechains is that 51% attacking them is made easy by default. Unless you negotiate deals with huge mining pools, there's not enough security, and BTC can be stolen from sidechains if miners attack it. So the idea of sidechains looks dependent upon mining centralization which is a big enough issue already.
I wholeheartedly agree with other posters. Blockchains just aren't good at certain use cases. You can't do HFT on a blockchain, even one with 10 second blocks. OTOH, the blockchain is censorship resistant and pseudonymous. In areas where excessive rules and regulations push out the little guy, the blockchain can be a solution.
His conclusion: "Is there value in Bitcoin? Let me ask a counter question: Is decentralization valuable? If you think that we'll increasingly lose trust in the central authorities that manage the infrastructure we rely on, you might expect Bitcoins to rise a lot in value. If not, that is you believe that authorities will be able to tackle the challenges of the future better in centralized form, then from your perspective Bitcoins don't add value. We'll see."
http://www.belmarca.com/2014/02/26/mt-gox-failure-and-opport...