Abstract Assessment 2

A double spend refers to:

Sending a transaction and the recipient resending that same transaction back to you, instantly.

Sending a transaction and then resending the same transaction with a higher fee to the same address prior to the confirmation of the original transaction.

Sending a transaction and then sending a different transaction spending the same funds to a different address prior to confirmation of the original transaction.

Sending a single transaction that is split into two separate transactions that then arrive at the same destination address in order to increase privacy.

2.Changing blocks that have had several blocks built on top of them is rendered almost impossible through the ____________.

Accumulation of proof-of-work

Cryptographic security layer

Byzantine generals dilemma

Block reward

3.Blocks are a _________i) for all the transactions they contain and represent a __________ii)

i) connection, ii) network.

i) timestamp, ii) proof of their existence and validity.

i) means of distribution, ii) blockchain.

i) privacy mechanism, ii) security layer.

4.The block solution represents proof that the node proposing the block has _________ necessary for that block to be valid.

Performed the work

Followed the rules

Found the transactions

Applied the encryption

5.A node must be able to keep up with the rest of the network in the tasks of downloading, _________ i) all of the transactions taking place in the world in real time. The hashing machinery used to generate ________ ii) votes for the most capable node, incentivising node operators to build the fastest most capable machines in order to attract the most ________iii)

i) validating and storing, ii) proof of work, iii) hash

i) securing and anonymizing, ii) blocks, iii) fees

i) storing and securing, ii) hash, iii) users

i) hashing and storing, ii) transactions, iii) proof-of-work