The Ripple / Stellar protocol is bad, so this is not a surprise. Ripple was invented before Bitcoin. Ripple/Stellar requires explicit trust, where Bitcoin does not. Also the distribution was widely known to be gameable (I know many people involved who managed to get free stellar). The only surprising thing is that Stripe and Ravikant invested in a technology which is obviously inferior to Bitcoin. Prof. Mazieré and JedMcCaleb have no significant background in economic research and it shows.
" Any distributed consensus system on the Internet must sacrifice one of these features."<p>is incomplete: a distributed consensus system (which is, at heart, a distributed database) <i>can not</i> have all three features... but there is no guarantee that a distributed database has <i>any</i> of those features.<p>As with everything else, execution matters.<p>If you're going to be recording history for financial transactions, you need to put immutability as your first goal. This is not compatible with unlimited space-time separation of trusted inputs, so the second thing you need is to decide how you're going to resolve inconsistent histories. Doing so <i>always</i> involves a centralized trusted system, even if it is fed from a distributed system: someone needs to decide what transactions really happened. You can claim that you have a distributed algorithm to do so (consensus) but that itself will always fall into the same distribution problem.<p>And that's what seems to have happened here.
I don't know what Stellar is. I had a look at their website. It's a decentralised [1] currency something or other. But this blog post states:<p>> We were able to replay most of these rolled back transactions on chain B to minimize the impact<p>And<p>> To ensure no ledger forks going forward in Stellar, we have decided to temporarily only run one validating node until the new consensus algorithm is live<p>I don't see the decentralisation here?<p>[1] <a href="https://www.stellar.org/learn/#Decentralized_network" rel="nofollow">https://www.stellar.org/learn/#Decentralized_network</a> "This means that the Stellar network does not depend on any single entity"
<p><pre><code> "Prof. Mazières’s research indicated some risk that consensus could fail, though we were nor certain if the required circumstances for such a failure were realistic."
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I'm surprised to see the above statement in a press release; maybe it was not worded quite right. At the scale of 100s of thousands, or a millions of transactions a day, "some risk" will manifest itself on operation timescales itself. So when one is "not certain" it's always best to assume that problems will show up and it will take less time than expected.<p><pre><code> "We are still investigating the triggers for this consensus failure, but believe it is caused by the innate weaknesses of the Ripple/Stellar consensus system outlined above compounded by the number of accounts in the network."
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Also not great wording. Saying the system had "innate weaknesses" and we "believe" kind of implies engineers are still guessing on the trigger. Your building a financial corporation and if you lose you loose everything
Ripple Labs' response:<p><a href="https://ripple.com/why-the-stellar-forking-issue-does-not-affect-ripple/" rel="nofollow">https://ripple.com/why-the-stellar-forking-issue-does-not-af...</a><p>(Ripple Labs develops the software that Stellar modifies for their own use, and the original Ripple network still runs on unmodified Ripple Labs software. Stellar was started by Jed McCaleb, who founded Ripple Labs, but broke with the CEO last year.)<p>The Ripple consensus protocol puts certain requirements on the topology of the network of transaction-validating nodes in order to work properly. They are still investigating, but it's possible Stellar's network fell outside the workable range. Ripple Labs manages their network topology more carefully than Stellar, and this incident may validate their approach. We'll have to see what actually happened.
I'm somewhat familiar with Bitcoin, and I've heard of Stellar, and my sense is they are related - both a decentralized consensus based ledger system. I'm wondering if the problem that Stellar encountered is something that Bitcoin has some resistance to. Anybody have some insight?
Well it was to be expected, Ripple scammed thousands of users with similar promises<p>They re-branded as "Stellar" + somehow got Stripe to give them a mention and the scam repeats