35
votes
Accepted
Is it possible to send pictures to the Tangle? What is the data limit per transaction?
Yes, you can upload images or any files or other data to the tangle.
As long as their size is less than 2187 trytes you can put them into one tx (=transaction). If they are bigger (=more trytes) than ...
- 4,444
27
votes
What does the IOTA coordinator actually do?
I think this copy/paste from Reddit explains it perfectly:
What is the Coordinator and what does it do?
Every minute [now 35 seconds] the Coordinator makes a normal transaction with its signature ...
- 1,099
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 ...
- 1,540
11
votes
Accepted
How is data stored in the tangle?
Your metaphor
putting luggage in an empty train and someone in the next station opens the door and gets the bags out
is actually quite accurate because that's basically whats happening. Except ...
- 4,444
8
votes
Accepted
What does the "block number" in the iota wallet represent?
The two numbers are the
the latest solid subtangle milestone index
The "latest solidsubtangle milstone" is used for sending transactions. For a milestone to become solid your local node (or whatever ...
- 4,444
8
votes
Accepted
Does every node in the network have to know about all transactions issued by other nodes eventually?
As of the current implementation state, every node will have to receive every confirmed transaction eventually (so that the solid subtangle milestone can increase and the node can calculate all ...
mihi♦
- 7,309
7
votes
Accepted
How can IOTA's proof of work provide sufficient network security?
What PoW means in practice is that cost spent on mining = security. Ie. $100 fees per hour? Spend >$100 (in energy used for mining) to rewind these transactions. It's better with asics as that adds '...
- 1,607
7
votes
Accepted
What is IOTA trading off giving up Blockchain and adopting DAG?
The biggest perceived "downside" of Tangle as opposed to Blockchain is that the cost of decentralization requires PoW in every transaction as opposed to centralizing it with miners.
Blockchain may be ...
- 3,135
7
votes
Extracting data from the tangle
Basically there are three ways to get to the data (depending on what you want):
Query the API of your node to find transactions and walk along them. This might be slow (depending on what you are ...
mihi♦
- 7,309
7
votes
Accepted
Is double spending possible in IOTA?
In short: double spending is incredibly unlikely in IOTA.
In IOTA, majority hashpower is insufficient for a double-spend attack. IOTA is unlike proof-of-work based blockchains in this regard. You ...
- 294
6
votes
What are the IOTA disk space needs?
I did a crude test based on the Tangle data available here http://store.alon-e.com/IOTA_DBs and then fitted a projection function to it.
So the whole size of the Tangle (counted from December 2016) ...
- 1,663
6
votes
What are the IOTA disk space needs?
What is the current size of the IOTA chain data?
Right now the whole IRI directory on my Ubuntu server is 5.2gb. The current database is 4.9gb and is likely due for a pruning (snapshot in IOTA terms)....
- 148
6
votes
How does a reattached transaction impact the tangle?
A transaction is only an envelope for the signed bundle that details the exact transaction of funds between addresses. The transaction gets attached to the Tangle by doing the Proof of Work and ...
- 314
6
votes
How can IOTA's proof of work provide sufficient network security?
"Hype aside it's a minor change that's equivalent to transaction chains in Lightning Network or Raiden, offering exactly the same advantages (asynchronous) and disadvantages (lower security)." - this ...
- 1,540
6
votes
Accepted
Pseudocode to walk the tangle?
Basic recursion for every open tip should do it. Just follow everything back to the origin or until you hit something you mapped already. I know that those object notations are very pseudo ;)
foreach(...
- 1,293
6
votes
Accepted
What is the goal of the Nash Equilibrium blog posts?
Here's my takeaway, and technical people please feel free to correct me:
This blog post is about how every node can pick their own tip selection algorithm, which is the method by which they decide ...
- 3,135
5
votes
Accepted
Transactions per second
I think you got something wrong there: 1-2 transactions per second is not the max amount of transactions possible, it's the amount of transactions people make.
On the live tangle, we have seen ...
- 3,135
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 ...
- 461
5
votes
How does a reattached transaction impact the tangle?
When you re-attach a transaction you don't take the old one out. You basically issue a copy of the same transaction.
So if the yellow transaction is already approved/referenced by the black ones, ...
- 1,663
5
votes
Accepted
What does it mean that "the tangle is network-bound instead of hash-power-bound like blockchain"?
The IOTA Tangle more network-bound than hash-power-bound because in order to perform an attack, you need to meet three conditions:
X [any number] percentage of network hash rate (depending on Y 34% ...
- 4,444
5
votes
Accepted
How long does the proof of work take today and in future?
Short answer it depends.
A little longer answer, the needed time for the proof of work depends on:
the device that calculates the hash.
the load of this device (with other stuff).
the ...
- 804
5
votes
In a transaction, what are "trunk", "branch" and "bundle" exactly?
Bundle
All individual transactions that make up the complete transaction share the same bundle hash. That bundle hash is unique to them. It is not an address hash or a transaction hash of another ...
- 921
5
votes
Persistence of important data on the Tangle
With the Tangle you can only really verify that a particular transaction was issued by a specific party but the data inside the payload must not really be true at all.
This is of course true but it ...
- 470
5
votes
Accepted
What is the blowball problem and what causes it?
The blowball problem is this phenomena where a huge quantity of new transactions select more or less at the same time the exact same transaction (most of the time the latest milestone) as branch and ...
- 5,344
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
...
- 71
4
votes
What is IOTA trading off giving up Blockchain and adopting DAG?
In addition to miners losing their jobs?
I guess probably the higher number of transactions and full nodes you need to achieve stability in the network. Also there are different kind of ...
- 1,607
4
votes
Difference between score and cumulative weight
Let x denote our transaction.
The score is backward-looking = weight of x + sum of weights of all transactions approved by our transaction x
The cumulative weight is forward-looking = weight of x + ...
- 1,663
4
votes
What are IOTA flash channels and how can users set them up?
Flash Channels
Flash is a bi-directional off-Tangle payment channel to enable instantaneous, high-throughput transactions. In essence, they provide a way for parties to transact at high frequency ...
- 3,135
4
votes
What is the difference between the Hashgraph and the Tangle from IOTA?
This is not a complete answer, but here are a few points:
IOTA is a cryptocurrency, whereas Hashgraph is an algorithm, i.e. there is no public ledger built on Hashgraph (yet)
IOTA is open-source ...
- 1,663
4
votes
Accepted
When do nodes sync their subtangle with the neighbours?
After looking into code of IRI : all incoming transactions that aren't known yet (i.e. not already stored in the local tangle) are immediately stored in the local tangle and broadcasted to all ...
- 5,344
Only top scored, non community-wiki answers of a minimum length are eligible