31 votes
Accepted

Without the Coordinator, how will the network decide which double-spend succeeds?

In every DLT, a transaction have a probability to be valid. (In Bitcoin, a transaction is valid as long as it is written in the longest chain, so the probability for your transaction to be invalid is ...
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  • 5,344
17 votes

Consensus - how is a single, non-conflicting graph (tangle) maintained?

IOTA uses Proof-of-Work as an anti-Sybil measure. Every transaction has some PoW tied to it, the transactions reference other transactions which the transaction issuer treats as valid, so a ...
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5 votes

Consensus - what convergence properties does the tangle have when multiple conflicting transactions are built upon by different parts of the network

I can't answer how it will behave in case the coordinator is shut down and the network is actually decentralized as described in the whitepaper. Right now, the branch that gets confirmed by the ...
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  • 461
4 votes

Consensus - what convergence properties does the tangle have when multiple conflicting transactions are built upon by different parts of the network

It is not easy to explain this in a few words. Therefore, I recommend to go over this consensus presentation first: https://github.com/noneymous/iota-consensus-presentation/blob/master/README.md ...
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  • 71
3 votes

What Proof of Work function does IOTA use?

IOTA's Proof of Work is directly comparable to Hashcash, as it serves a similar purpose to prevent spam, and in our case, also to prevent sybil-attacks. -Official IOTA FAQ More about the Hashcash ...
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  • 103
3 votes

How can there be consensus once the tangle is too large for a single iri node to track?

A single IOTA node can already handle around 1000 transactions per second, this is quite a bit but probably not enough in the future. Once this becomes an issue sharding can be a solution. This means ...
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  • 1,099
2 votes

What Proof of Work function does IOTA use?

Iota currently uses Curl hashing algorithm for proof of work. It was developed internally by IOTA team as a ternary (uses base 3 numbers, like all Iota, instead of binary) cryptographically secure ...
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  • 461
2 votes

Without the Coordinator, how will the network decide which double-spend succeeds?

Generally speaking, the double-spend which is directly and indirectly referenced by more transactions (i.e. has a larger cumulative weight) will most probably get confirmed. This is because more nodes ...
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  • 1,663
2 votes

How is consensus achieved in offline transactions?

When a part of the network (e.g. a satellite swarm of 4 devices, each are IOTA full nodes, floating into space planning to return in 4 years) decouples from the rest of the network a Subtangle is ...
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  • 4,459
2 votes
Accepted

Will the network and nodes be distributed after coordinator removed?

The coordinator plays a role in the network today only because fullnodes accept it. The current version of the IRI handle milestones (i.e. transactions issued by the coordinator) with specific code (...
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  • 5,344
2 votes

Finding a double-spending inner conflict referencing two tips

It traverses through ancestors until it reaches a recent memory-persisted snapshot of balances, creates a new potential state, and then checks to see whether any addresses resolve to a negative value.
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  • 316
2 votes

Immutability in IOTA: How to be sure a transaction is not "removable" from Tangle?

At the moment, we rely on Milestones issued by the Coordinator. In the future we might be able to rely on weight, which is the DAG equivalent of chain length. I don't know if Iota will need a ...
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  • 4,459
1 vote

Does Iota share its consensus algorithm with google ai?

MCMC ("Markov Chain Monte Carlo") is used for tip selection in IOTA. It is not mandatory, but the default iri algorithm (see Does the Tangle enforce a tip-selection algorithm?) White paper says: "...
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1 vote

Does Iota share its consensus algorithm with google ai?

I am pretty sure that the name is a coincidence. In general statistics, "Monte Carlo algorithm" refers to an algorithm that does not calculate an exact result, but performs several random simulations ...
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  • 7,254
1 vote

impact of a single double-spend to the network

Double spends are resolved once your transaction or bunch of transactions is attached to the main tangle. 1) COO in mainnet: The COO emits milestones every minute. Once your transaction is indirectly ...
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1 vote

GPU Proof-of-work

A team working on a spamming tool tried to implement GPU transaction spammer but they ran into big issues with OpenCL as of 20/2/2018. The library is not ready as it always crashes, so it's whether to ...
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1 vote

GPU Proof-of-work

IOTA has some OpenCL context Library: https://github.com/iotaledger/clcontext But I don't know what you can do with it. Maybe this is what people ware referring to.
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  • 840
1 vote

Consensus - what convergence properties does the tangle have when multiple conflicting transactions are built upon by different parts of the network

When a node gets word of a larger conflicting graph by what logic does it decide between the two? This is not how the nodes work. The node just selects random tips from its stored tangle to use ...
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  • 470
1 vote

How is consensus achieved in offline transactions?

Offline transactions (AKA flash channels) requires an online tx to start and an online tx at the end. In the meantime, all transactions between participants can be offline. (be aware that 'offline' ...
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  • 5,344

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