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Stellar Protocol: A Federated Model for Internet-Level Consensus (2016) [pdf]

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Re: Stellar Protocol: A Federated Model for Internet-Level Consensus (2016) [pdf]

#11

Post by narrator »

ketzu wrote: post #9
narrator wrote: post #6

Leader election in distributed systems is still an unresolved problem AFAIK except for proof of work. The problem is what does the leader have to give up to be a leader? The economic value of being the leader must be balanced by the work to become the leader otherwise there is an opportunity for arbitrage. For instance, if the value of leadership is X and the cost to do a Sybil or other attack is X/10 the network wil…

You seem to use a very narrow definition of "distributed system" compared to most people. Could you explicitly state your assumptions? Your "distributed system" seems to coontain assumtions such as trustlessness and openness towards new participants. (No sybil attacks with fixed entities)

Yes, I was assuming a cryptocurrency situation in which the system is open, new participants can join, and it must work under byzantine fault-tolerant conditions. In a system such as RAFT or PAXOS this isn't the case and thus these systems can properly elect leaders.

Re: Stellar Protocol: A Federated Model for Internet-Level Consensus (2016) [pdf]

#12

Post by nullstyle »

desireco42 wrote: post #5
suckmydang wrote: post #3

When Stellar's codebase was still just a fork of Ripple (entire codebase was completely re-written from scratch in 2015), it experienced many divergent forks of the network due to weaknesses in the Ripple consensus protocol. Those weaknesses have been eliminated in the new SCP described in this paper, but AFAIK Ripple still has these systemic problems. The new Stellar codebase is actually a joy to work with.

I know their api is really nice and I was surprised how easy was to work with it, whether it is a test net or public.

Thanks for the kind words! (disclosure: I designed most of the API)

We're not done yet. IMO it's still not easy enough to build great software on top of our work.

Re: Stellar Protocol: A Federated Model for Internet-Level Consensus (2016) [pdf]

#13

Post by ChristianBundy »

desireco42 wrote: post #5
suckmydang wrote: post #3

When Stellar's codebase was still just a fork of Ripple (entire codebase was completely re-written from scratch in 2015), it experienced many divergent forks of the network due to weaknesses in the Ripple consensus protocol. Those weaknesses have been eliminated in the new SCP described in this paper, but AFAIK Ripple still has these systemic problems. The new Stellar codebase is actually a joy to work with.

I know their api is really nice and I was surprised how easy was to work with it, whether it is a test net or public.

Seriously: Stellar is _by far_ the easiest asset exchange platform I've ever worked with. It's completely silly, but it took me five minutes to create an IOU for a beer and send it to a friend (which they can "withdraw" as a free beer IRL at any time).

I'm deeply skeptical of most altcoins, but Stellar is going places.

Re: Stellar Protocol: A Federated Model for Internet-Level Consensus (2016) [pdf]

#14

Post by bradleyjg »

alistproducer2 wrote: post #10
narrator wrote: post #6

Leader election in distributed systems is still an unresolved problem AFAIK except for proof of work. The problem is what does the leader have to give up to be a leader? The economic value of being the leader must be balanced by the work to become the leader otherwise there is an opportunity for arbitrage. For instance, if the value of leadership is X and the cost to do a Sybil or other attack is X/10 the network wil…

In distributed ledgers, it doesn't matter who the leader is. The system only has to ensure that leadership is distributed in such a way that it is statistically infeasible or economically unprofitable to rewrite history. PoW distributes the leadership (block creation) via crypto puzzles. PoS tries to use economic incentives to make bad behavior more expensive than good. There's work being done (which I personally bel…

Isn't the problem with random selection, that if there's very little cost to enter then a bad actor can flood lottery with entries?

Re: Stellar Protocol: A Federated Model for Internet-Level Consensus (2016) [pdf]

#16

Post by zeroxfe »

cantrip wrote: post #8
neuronexmachina wrote: post #2

I was curious about how this was different from Ripple's approach, I thought this was interesting: > Generally, membership in Byzantine agreement systems is set by a central authority or closed negotiation. Prior attempts to decentralize admission have given up some of the benefits. One approach, taken by Ripple, is to publish a “starter” membership list that participants can edit for themselves, hoping people’s edit…

What part of this is interesting to you? This paragraph does not explain how they are different from Ripple's approach only that they are in fact different.

> This paragraph does not explain how they are different from Ripple's approach only that they are in fact different.

I think the last line sums it up: "SCP is the first Byzantine agreement protocol to give each participant maximum freedom in choosing which combinations of other participants to trust."

As opposed to Ripple, where the trust is heavily biased towards the starter membership list, making it more centralized than one would want.

Re: Stellar Protocol: A Federated Model for Internet-Level Consensus (2016) [pdf]

#17

Post by avdempsey »

bradleyjg wrote: post #14
alistproducer2 wrote: post #10

Earlier quoted context omitted.

In distributed ledgers, it doesn't matter who the leader is. The system only has to ensure that leadership is distributed in such a way that it is statistically infeasible or economically unprofitable to rewrite history. PoW distributes the leadership (block creation) via crypto puzzles. PoS tries to use economic incentives to make bad behavior more expensive than good. There's work being done (which I personally bel…

Isn't the problem with random selection, that if there's very little cost to enter then a bad actor can flood lottery with entries?

My understanding is they try to mitigate this by having a minimum account balance to participate.

Re: Stellar Protocol: A Federated Model for Internet-Level Consensus (2016) [pdf]

#18

Post by desireco42 »

nullstyle wrote: post #12
desireco42 wrote: post #5

Earlier quoted context omitted.

I know their api is really nice and I was surprised how easy was to work with it, whether it is a test net or public.

Thanks for the kind words! (disclosure: I designed most of the API) We're not done yet. IMO it's still not easy enough to build great software on top of our work.

Whoa, awesome, well, thank you personally. I find it surprising the UI is pretty rudimentary taking into account how API is easy to work with.

I am looking to do something, not 100% what on Stellar Network, mostly due to the fact that I am familiar with it and I like api among other things.

Re: Stellar Protocol: A Federated Model for Internet-Level Consensus (2016) [pdf]

#19

Post by jcfrei »

alistproducer2 wrote: post #10
narrator wrote: post #6

Leader election in distributed systems is still an unresolved problem AFAIK except for proof of work. The problem is what does the leader have to give up to be a leader? The economic value of being the leader must be balanced by the work to become the leader otherwise there is an opportunity for arbitrage. For instance, if the value of leadership is X and the cost to do a Sybil or other attack is X/10 the network wil…

In distributed ledgers, it doesn't matter who the leader is. The system only has to ensure that leadership is distributed in such a way that it is statistically infeasible or economically unprofitable to rewrite history. PoW distributes the leadership (block creation) via crypto puzzles. PoS tries to use economic incentives to make bad behavior more expensive than good. There's work being done (which I personally bel…

> There's work being done (which I personally believe is the right way to go) in using a leader election-based system that works like a lottery (Algorand[0] is an example).

Probably what you meant but I still wanted to mention it: Bitcoin (or most PoW schemes) work like a lottery. Think of each attempt at generating a nonce below the required difficulty as a lottery ticket. The more nonces you generate (the more hashes per second you compute) the higher your chance of winning. The system works because people who spent lots of money on lottery tickets in the past (and maybe won one or two times) are incentivized to keep the lottery running in an honest manner (so their prize keeps its value - if they haven't spent it).

> Along these lines one of the more intriguing projects is called RandHound[1]. It's a way of creating distributed randomness (according to the paper's title). I think chains secured via lottery leader selection protocol has more promise than PoS.

Another notable mention is dfinity (dfinity.org). They have a very interesting technology stack and I'm hoping for discussions about it in the future on HN.

Re: Stellar Protocol: A Federated Model for Internet-Level Consensus (2016) [pdf]

#20

Post by cantrip »

zeroxfe wrote: post #16
cantrip wrote: post #8

Earlier quoted context omitted.

What part of this is interesting to you? This paragraph does not explain how they are different from Ripple's approach only that they are in fact different.

> This paragraph does not explain how they are different from Ripple's approach only that they are in fact different. I think the last line sums it up: "SCP is the first Byzantine agreement protocol to give each participant maximum freedom in choosing which combinations of other participants to trust." As opposed to Ripple, where the trust is heavily biased towards the starter membership list, making it more centrali…

How exactly does that work?

To me, the statement says essentially "you can trust us more than Ripple" with no explanation as to why.

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