Ask HN: How does consensus work in an enterprise blockchain?

https://news.ycombinator.com/item?id=15915520

by thisisit • 9 years ago

33 34 9 years ago

news.ycombinator.com

We have seen a lot of focus given to bitcoin's PoW and the electricity usage. This got me thinking how the enterprise offerings like Quorum, Hyperledger work exactly? Are they like a PoS model?

Edit: Based on the inputs, I wanted to add couple more questions.

If the consensus is based on a set of trusted accounts, why are people using the enterprise blockchain stuff still talk about blockchain being "trustless"?

Second, if it is only about a set of shared ledger with multiple trusted parties, what is wrong with an API layer integration? What exactly is the value creation for a full fledged system?

Third, bitcoin blockchain defends against a miner getting hacked by making everyone do PoS. Sure coins will get stolen.

But, if we have a permission-ed server which can add stuff to an enterprise blockchain doesn't it make the whole thing a lot less secure?

dozzie9• 9 years ago

How does consensus work in an enterprise blockchain?

It doesn't, because blockchain doesn't solve consensus problem.

econner• 9 years ago

What's the point of using a blockchain then?

prepend3• 9 years ago

There’s tons of answers to this, but one example I’m interested in is as a good shared, accessible audit log for data throughout an organization. Just having a stable history for all data helps with investigation and master data management.

In this case consensus isn’t really necessary because all participants are trusted and should rarely differ (since they all have the same boss at some level).

dozzie9• 9 years ago

To tell which document (transaction) of a given pair correlated ones was issued earlier, which is called "timestamping". But you don't need consensus (as in Byzantine generals problem) to do that, you just need timestamping protocol.

blueplanet200• 9 years ago

Maybe explain a little more? Obviously in your opinion the OP is confused, but this answer is short and unhelpful.

dozzie9• 9 years ago

First and foremost: what is consensus problem?

YuriNiyazov5• 9 years ago

A trustless blockchain most certainly does. https://news.ycombinator.com/item?id=15915957

dozzie9• 9 years ago

It most certainly doesn't. You even confuse blockchain and Merkle trees, and call into existence some weird term "distributed blockchain".

But then, consensus problem is a problem of establishing a specific value for almost all participants. Which implies that the value is established, which means that the protocol terminates. Blockchain was not designed to ever terminate, so it's not a consensus protocol even if for no other reason.

Otherwise, what parts of blockchain exactly establish a common value among participants and what exactly is this common value?

heckerhut• 9 years ago

It’s based on a quorum of white-listed accounts that are allowed to sign blocks.

YuriNiyazov5• 9 years ago

When the Bitcoin paper originally came out, it used the word 'blockchain' to specifically mean a 'trustless distributed blockchain' where consensus is reached via mining, and that is susceptible to a 50% + 1 attack, and where the mining nodes are individual businesses that have no reason to trust each other except that the game is set up in a way that it is in their self-interest to secure the blockchain.

However, there's a use for the word 'blockchain' which is 'distributed blockchain', which is a data structure that is a chain of blocks where each includes a hash of the previous one - it's distributed amongst machines, but those fundamentally trust each other (like in case of JPMorgan chain), so there's no reason to use a 'trustless distributed blockchain'. You can't set up a miner and join Quorum and make money securing it. In such a case, quorum is probably solved just using standard distributed database algorithms like Paxos or Raft.

0xf8• 9 years ago

JPM's Quorum is originally a fork of Ethereum though.

YuriNiyazov5• 9 years ago

Sure, but it's permissioned. Not everyone can join and mine.

russdpale2• 9 years ago

Huh? Bitcoin white paper does not have the word block-chain in it.

prepend3• 9 years ago

Yet it describes the blockchain. It talks about blocks, it refers to them in a chain. While true that the word block-chain doesn’t exist, it isn’t relevant to OP’s point (since the paper clearly defines the blockchain concept now used so prevelantly).

borplk• 9 years ago

It may not have the "blockchain" exactly but it certainly does have blocks and mentions chaining them together.

viraptor• 9 years ago

Second, if it is only about a set of shared ledger with multiple trusted parties, what is wrong with an API layer integration? What exactly is the value creation for a full fledged system?
But, if we have a permission-ed server which can add stuff to an enterprise blockchain doesn't it make the whole thing a lot less secure?

You're asking the right questions and this is pretty much a summary why the enterprise use is unlikely to use blockchain the same way as the public, if at all. Enterprise/banking may be interested in a distributed ledger as a datastructure, but other tech which provides a similar results already exists.

Unfortunately if you look at most of the "big (company/bank) starts (experimenting with/using) (Bitcoin/blockchain)" news, they very rarely say why and how.

brudgers• 9 years ago

As your edit notes, trust solves a lot of the technical hurdles that Bitcoin and Etherium and other protocols intended for use against adversaries must leap.

Many of the proposed and actual uses of blockchain are layered on top of existing trust networks. For example inter-connected electrical grids operated by separate companies already trust each other and already have working settlement mechanisms. Potentially a blockchain can improve/simplify/quicken an existing flow of settlements between trusted parties by eliminating phonecalls, faxes, snail mailed bank drafts, and so on. It may reduce manual processing and human error and banks in the middle.

As a technology, blockchain may be more like double entry accounting or an abacus than the many other things that the word "technology" tends to conjure up in our minds.

narak• 9 years ago

Worth watching this talk on Ripple's consensus algorithm by its architect: https://www.youtube.com/watch?v=7abKUs9tYZg and related whitepaper: https://ripple.com/files/ripple_consensus_whitepaper.pdf

I have no affiliation with Ripple or XRP, just enjoyed the fairly technical nature of the talk.

nnn1234• 9 years ago

The goal would be to enable co opetition. Think of patent pools, the incentive usually is to own the patent and enforce it, inside of patent pools however , the goal is to get to application. So a collection of non trusting entities can have a shared ledger of record.

That most certainly is the pull, which Enterprise blockchain cos sell as simplified back office.

Will it work like that in production ? No clue

Ask HN: How does consensus work in an enterprise blockchain?

Related Stories