Ripple

Question 1

Paxos

Answer 1

Algorithm which tries to allow consensus solving and enable cft algorithms

Question 1

IOU Payments: Entities trust other entities for some amount
=> if a chain from entity A to entity B exists and every node in the chain trusts its neighbour for atleast amount x A can issue x to B

Question 2

transactions in ripple

Answer 2

payment, accountset, setkey(change key to sign), offercreate, offercancel, trustset(change trust between entities)

Question 3

Consensus in ripple

Answer 3

Collection Phase: Validating servers collect transactions received by network check for authenticity, signatures, put the transaction together in merkle tree and include in block
Consensus Phase: Validating servers sends each other proposals => if more than 80% of UNL agree block is consented upon
Ledger closing Phase: Once 80% consensus is reached all validating servers must sign the ledger, ledger is closed once atleast 80 of UNL did this

Question 4

Stellar

Answer 4

Fork from Ripple which changed some of the consensus algorithm and tries to fix forking problem