the native currency of the Blockchain. It’s usually believed that
people who have invested in a network heavily would be less likely
to harm the network on their own. Such consensus process is easily
faster, scalable, and more energy efficient than PoW.
1.5.5.3 Delegated Proof of Stake (DPOS)
In DPOS, only some elected subsets of all the stakeholder nodes are
allowed to validate the transactions. This process of election keeps
on happening in regular time interval, so that all the nodes would get
their turn to be validators at some interval. Such a consensus
process is even faster and more efficient than PoS, as less number
of nodes take the decision as they take lesser time to reach a joint
consensus.
1.5.5.4 Practical Byzantine Fault Tolerance or
PBFT
Before discussing PBFT, we must understand BFT or “Byzantine
Fault Tolerance”. BFT refers to the Byzantine Generals’ Problem,
widely used in computer science for a war situation where multiple
generals of the same party must agree on a single war strategy to
attack a city; however, it also considers the risk that some of these
generals might be corrupt or not trustworthy.
When it comes to a distributed system, BFT is a feature for fault
tolerance or resistance to failure, even if some of the nodes fail or
act maliciously. There are many different solutions to handle this type
of issue; however, PBFT is considered as the gold standard.
Practical Byzantine Fault Tolerance or PBFT is a mechanism through
which a collective decision can still be made by all the nodes even in
a war-like difficult situation. In PBFT, at one time, there can be one
leader node and the rest will work as followers; also, the follower
nodes can take their turn to be a leader node. When a client sends a
request, it is attended by the leader node of that time. The leader
node broadcasts the message to all the follower nodes who send the
responses back to the client. The client has to wait till the “N+1”
responses from different nodes, where “N” is the maximum number