Questions tagged [blockchain]
23 questions
79
votes
5 answers
What important/crucial real-world applications use blockchain?
As part of some blockchain-related research I am currently undertaking, the notion of using blockchains for a variety of real-world applications are thrown about loosely.
Therefore, I propose the following questions:
What important/crucial…
rshah
- 873
- 1
- 7
- 12
6
votes
1 answer
Why are forks in the Blockchain eventually resolved?
I'm reading Wattenhofer's The Science of the Blockchain. On page 87, he states the following thoerem:
Theorem 7.22. Forks are eventually resolved and all nodes eventually agree on which is the longest blockchain. The system therefore guarantees…
Zirui Wang
- 1,028
- 6
- 13
5
votes
1 answer
What is the algorithm for Blockchain's Byzantine Fault Tolerance?
This person was asked: "Why is a blockchain implementation different than a distributed consensus system like Raft?"
In part of their answer they replied:
For one, Raft is not Byzantine fault tolerant, i.e., not designed to account for arbitrary…
hawkeye
- 1,199
- 8
- 20
3
votes
1 answer
How to generate, validate, and invalidate a set/list of numbers in O(1) time and space?
Imagine my server is generating "tokens" of some sort for a client on a regular basis. When a client asks for a token, the server responds with a new value (and any other supplemental information it wants to, like a "witness"). Later, the client…
Taytay
- 131
- 4
2
votes
0 answers
Agreeing on a Time in a Trustless Network
Imagine a chord-like network $N$. each machine $m \in N$ is directly connected to $N_m \subset N$.
Without relying on official timeservers, I want all machines to synchronize to some time with millisecond precision.
my algorithm is executed some…
option 12
- 21
- 2
2
votes
1 answer
Blockchains where new users don't need to wait for a new node to retrieve old transactions?
After watching 3b1b's brief primer on blockchains here, I noticed a bit of a "flaw" with blockchains. It isn't really a flaw, but I'm not sure how it is alleviated.
If we have two players, Alice and Bob, who are transacting with one another, each…
Andrew Baker
- 327
- 1
- 6
2
votes
1 answer
How do these Crypto terms relate to each other and what do they all mean?
Alright this is another day of my pursuit to learn about how crypto works. I have several terms that I have found linked together. I was trying to do research on how the Target Hash is determined and how a Nonce is decided. But I think I am getting…
Joe
- 51
- 3
2
votes
0 answers
What is the difference between Proof of Elapsed Time (PoET) and Practical Byzantine Fault Tolerance (PBFT) algorithm?
I am interested in these two consensus algorithms in the blockchain: PoET and PBFT.
I saw this question about PBFT algorithm.
But, my questions are: what is the difference between PBFT and PoET algorithm? Are they the same? If no, when to consider…
David Setyanugraha
- 21
- 1
1
vote
1 answer
Is it possible to "encrypt" a function?
function createUser(data) {
var time=Date()
var newUser=new User(data.username)
newUser.setCreateDate(time)
var res={result:newUser,duration:Date()-time}
return res
}
so maybe i'd like to put that on a smart contract, but i don't want the…
Computer Scientist
- 11
- 2
1
vote
1 answer
How can information be updated in blockchain?
I am learning about blockchain and I've read that blockchains are immutable. Suppose my health information is stored on a block and I have gotten diagnosed with a disease and now my information needs to be updated. I have read online (here) that to…
Kunal
- 13
- 3
1
vote
0 answers
CLRS like book for blockchain?
I am writing a blockchain as a side project in Go and I am struggling to find good a theoretical treatise on the subject.
The information online is either too basic or too specific.
Thanks
Lumbda Kokolala
- 11
- 2
1
vote
1 answer
Why is "Proof of Space" insufficient to secure a blockchain?
I just came across a blockchain concept called "Proof of Space-Time" in which participants compete to verify blocks by generating and storing essentially random data to answer essentially random cryptographic challenges. The more data they can…
feetwet
- 127
- 1
- 7
1
vote
1 answer
Guaranteed existence of a blocking set in the accept definition of Stellar
In the SCP, condition 2 of the accept definition allows a node to vote for one statement and later accept a contradictory one. Condition 2 assumes the existence of a v-blocking set which has not only voted for a but also accepted it. What is the…
nbcb
- 21
- 2
1
vote
1 answer
Where were the ideas of vote, accept and commit phases originally introduced?
In the Stellar Consensus Protocol SCP, the voting procedure follows a 3 phase commit i.e. vote, accept and confirm i.e. see section 5.
Is this a novel introduction or has this been previously been introduced, and if so, where? More specifically, I…
nbcb
- 21
- 2
1
vote
0 answers
A tree-like data structure with rights delegation for distributed computing
Every actor can create a root node and delegate a right to add a child node. Every node contains name of its’ creator or who added it, and value S. Sum of all values S at the same level of the tree must be equal to the sum of all values of the…
nuwus
- 11
- 2