SHA-1 is the most commonly used SHA algorithm, and produces a ______-byte hash value(size).
Answer : D
Explanation:
SHA-1 is the most commonly used SHA algorithm, and produces a 20-byte hash value.
Reference:
https://www.securityinnovationeurope.com/blog/page/whats-the-difference-between-hashing-and-encrypting
What type of attack would be considered a very large flaw in public blockchains such as Bitcoin"™s Blockchain where the majority of hashpower could possibly be controlled thru an attack?
What is the specific attack Bitcoin could be exposed to?
Answer : A
Reference:
https://blockgeeks.com/guides/hypothetical-attacks-on-cryptocurrencies/
How many satoshis are in 1 bitcoin and how many wei in an Ether? (Select two.)
Answer : AB
Reference:
http://www.btcsatoshi.com/
In the Proof of Stake(POS) algorithm the miners are really known as ___________?
Answer : C
Explanation:
Proof of Stake has the same goal as proof of work""to validate transactions and achieve consensus in the chain""and it uses an algorithm but with a different process. With proof of stake, the creator of a new block "is chosen in a deterministic way, depending on its wealth, also defined as a stake." Since in a proof of stake system, there is no block reward, but the miners, known as forgers, get the transaction fees. Proponents of this shift, including Ethereum co-founder Buterin, like proof of stake for the energy and cost savings realized to get to a distributed form of consensus.
Reference:
http://www.hl.co.uk/news/2018/2/16/a-brief-history-of-blockchain-technology-everyone-should-read
A Byzantine failure is the loss of a system service due to a Byzantine fault in systems that requires________.
What is required?
Answer : A
Explanation:
A Byzantine failure is the loss of a system service due to a Byzantine fault in systems that require consensus.
Reference:
https://en.wikipedia.org/wiki/Byzantine_fault_tolerance