When a party within the network has found a solution, the block is

broadcasted that it wants to add to the chain together with the found

solution of the previous block.

The block is added by the rest of the network after verifying this solution.

The parts of the network may get isolated for a while resulting in multiple

branches in the chain occurring.

Each party in the network will choose the longest chain available and work

further on that branch only, in this case.

The block content consists of the new transactions as well as the hash

of the previous block and the previous solution, which means that

altering one block implies altering the hash of all blocks coming after

it.

The rest of the network adopts only the longest chain.

It is very time and resource-consuming to calculate the solution of a

block.

Conflict and its resolution

When blocks are created at roughly the same time by multiple miners, a

conflict is said to occur. The blocks take time to be shared across the

network, and so the question that arises is which one should be counted as

the legit block.

It can be assumed that all the nodes having synchronized on the network in

their blockchain are all on block number 5 0. If three miners across the

world create “Block 5 1” at roughly the same time, then which “Block 5 1”

should be considered valid? Each “Block 5 1” created by the three miners

will look slightly different, containing a different payment address for the

25 BTC block reward, and they may contain a different set of transactions.

Let’s call these blocks5 1a, 5 1b, and 5 1c.

►

Block 5 1a

Block 48 ►

Block 49 ►

Block 5 0 ►

Block 5 1b

►

Block 5 1c

Which block should be counted as the legit block?