A guarantee that a system will continue to provide data, and that no centralized authority can shut down its services.
What Is Liveness?
This means that a system has liveness guaranteed.
Distributed systems have a degree of correctness, and this involves an ordering of transactions. There are two elements involved in this — liveness and safety.
Liveness guarantees that good things will happen eventually, meaning there is no timeframe for these things to happen.
Termination of a distributed computation is one of many examples of liveness.
Liveness is the guarantee that all validators will reach some consensus on a value.
This can be thought of as the guarantee that no two validators will be in disagreement and reach different values.
Conversely, safety is a guarantee that nothing bad will happen.
The history and the expected history will be the same if nodes were honest.
A node which is a copy of the ledger operated by a participant of the blockchain network should not show different values when compared to another node.
Two nodes yielding different values represents a problem.
Nodes must reach agreement on what the next block should include.