99 votes
Accepted

What important/crucial real-world applications use blockchain?

Apart from Bitcoin and Ethereum (if we are generous) there are no major and important uses today. It is important to notice that blockchains have some severe limitations. A couple of them being: It ...
Pål GD's user avatar
  • 15.5k
26 votes

What important/crucial real-world applications use blockchain?

There are varying definitions of blockchain, and the answer to this question depends a lot on whether you consider the broad or the narrow interpretation. Typical cryptocurrency implementations such ...
jpa's user avatar
  • 449
11 votes

What important/crucial real-world applications use blockchain?

The given answers focus on the open p2p blockchains of Bitcoin and its likes. There is however also such initiatives as Hyperledger, R3 Corda, and Enterprise Ethereum Alliance, etc. (Even cloud ...
O.O.'s user avatar
  • 211
7 votes

Why are forks in the Blockchain eventually resolved?

If we simplify and assume that each miner randomly guesses a hash (as opposed to being more systematic) and we discretize time, say into minutes, then each minute each miner is hoping to "roll" the ...
Derek Elkins left SE's user avatar
4 votes
Accepted

What is the algorithm for Blockchain's Byzantine Fault Tolerance?

Actually the differences are more intricate than that. A problem here might be that the properties of "blockchains" are not very well specified and the term is used for a wide variety of things (going ...
Leonidaz0r's user avatar
1 vote
Accepted

Reference request: Time and proofs of a shared past

The happened-before relation is a standard mathematical tool for reasoning about time ordering of events in distributed systems. You can find a lot of development on foundations of it, tools for ...
D.W.'s user avatar
  • 156k
1 vote

How do these Crypto terms relate to each other and what do they all mean?

It really depends on the crytocurrency you are looking at. I will take example on Bitcoin here. Also, Bitcoin has gone through lots of changes which makes it difficult to track everything. For example,...
user123's user avatar
  • 1,092
1 vote

How to generate, validate, and invalidate a set/list of numbers in O(1) time and space?

The easiest and secure method of doing this is making a token an (id, signature) pair where you randomly generate a fixed-size id (e.g. 128-bits) using a method that avoids collisions (a hash of a ...
orlp's user avatar
  • 12.7k
1 vote

What happens when the xor inBlock chaining returns false?

Say you have blocks ABCDEA that you want to encrypt. If you do this naively, then the first and second A produce the same encrypted result, and an attacker would know that your first and last block ...
gnasher729's user avatar
  • 28.3k
1 vote

BlockChain: Always get a new Hash

Blockchain uses a cryptographic hash function that is designed to have collision resistance. Thus, while it's possible you might run into a pair of inputs that produce the same output... it's very ...
D.W.'s user avatar
  • 156k
1 vote

Guaranteed existence of a blocking set in the accept definition of Stellar

What is guaranteed is that if a quorum of an intact nodes accepts a statement s, then eventually every intact node v will find itself v-blocked by a set of nodes that has accepted s, i.e. "accept s" ...
nano's user avatar
  • 166
1 vote

Where were the ideas of vote, accept and commit phases originally introduced?

This dates back to the Byzantine broadcast algorithm of Bracha: Bracha, Gabriel. "Asynchronous Byzantine agreement protocols." Information and Computation 75.2 (1987): 130-143.
nano's user avatar
  • 166
1 vote

Incentive for block creation in a private blockchain

The blockchain would no longer be completely decentralized. You would have a dictator, or a central authority that decides which transactions get processed and which do not. At this point you could ...
Pål GD's user avatar
  • 15.5k

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