Crypto Academy Season 3 // Beginners course - Task 4 // Consensus Mechanisms. For Professor @sapwood // By @ononiwujoel

Hi professor @sapwood, I am @ononiwujoel one of your students in Crypto Academy and a member of the steemit platform. This is my homework submission post from your lecture Beginners course - Task 4 and I'll be writing on the question 2.

(2) What is the difference between PoS & DPoS? Advantages & Disadvantages? Name a few Blockchain projects which use the DPoS consensus mechanism and indicate the scaling capacity?

Introduction

There are some vital measures that must be adhered to for a decentralized blockchain to function smoothly without confusion and unnecessary disruption because it is very different from the centralized systems where we have a board of directors or central authority that makes rules to control every activity in the system. Decentralized system do not have a central controlling authority so there must be an agreement between everyone on the system as to how the system should operate.

Now this brings us to the consensus algorithms or protocol as a standing agreement with which collective decisions can be made without disruptions and collision of interests. And with the consensus protocol we can be sure to have a valid and well organised blockchain.

There are different types of consensus protocol/algorithms which include the Proof-of-Work(Pow), Proof-of-Stake(PoS), Practical Byzantine Fault Tolerance(PBFT), Delegated Proof-of-Stake(DPoS), Proof-of-.Burn etc. But from the assignment question I'll be writing on Proof of Stake and Delegated Proof of Stake.

Difference between PoS and DPoS

From the names PoS and DPoS we can tell that these are quite similar consensus protocols but there are still few differences between them which includes;

DPoS (Delegated Proof of Stake)	PoS (Proof of Stake)
The main difference between PoS and DPoS is the fact that in DPoS, stakeholders can delegate their influence (stake) to other users thereby making them able to use the delegated power as long as it remains delegated	In PoS there no provision for delegation of power/influence to another person.
In DPoS, active delegates can be voted into their positions by stakeholders	In PoS there's no voting of delegates instead stakeholders with higher influence takes the positions of validators
DPoS have a higher scalability or Scaling capacity than PoS	PoS have a lower scalability than DPoS
DPoS is actually the most decentralized consensus protocol as it fully engage the social system	PoS is less decentralized than DPoS
DPoS is less popular than PoS because it's actually new compared to PoS and many people are yet to understand it well	PoS is more popular than DPoS because it is the common alternative to PoW which happens to be the first consensus protocol in the blockchain technology

Advantages of PoS

• PoS do not require electricity or large amounts of energy to function smoothly unlike some other consensus protocol like PoW

• PoS do not require powerful and expensive equipment for mining but simple devices, and ownership of tokens

• It is very difficult to attack the PoS system because even if by chance someone meets the requirement to be able to attack the blockchain, he would be the biggest loser.
  To attack the PoS protocol, the user must own more than half of the assets in the blockchain.

• PoS is very popular among blockchain users. Infact it is just behind PoW when it comes to popularity so it enjoys a great deal of confidence from token holders

• Finally, PoS encourages people to hold more tokens (to be stakeholders).

Disadvantages of PoS

• Whales (users with very huge stake) can control the system to their own advantage as well as exploit miners in PoS

• Users with lower stake has little or no power to participate in decision making in PoS and may find it difficult to access any benefits

• Due to fact that this consensus protocol is based on stakes, higher stakeholders can make it very centralized and thereby defeat the purpose of the blockchain technology

Advantages of DPoS

• DPoS is the most decentralized consensus protocol because it almost runs like a true democracy where delegates can be voted into roles and also voted out if they underperformed

• DPoS do not require powerful equipment and energy for mining too just like PoS it can be done with simple devices and ownership of tokens

• Due to the structure of DPoS it encourages the users to engage socially among themselves especially in choosing delegates and as such adds more beauty to the blockchain technology

• DPoS is very common among new blockchains coming up as many has found it to be very decentralized and social too

• It is also very difficult to attack the DPoS blockchain due to it's high decentralized nature

• It has a better scalability than most consensus protocols

Disadvantages of DPoS

• Lower stakeholders have very limited influence on decision-making in the system and also have little access to benefits compared to higher stakeholders

• Whales with enormous stakes can also influence the system for their own selfish benefits.

• It is very difficult to make a difference in DPoS when you are a lower stakeholder

Blockchains that use DPoS

There are a number of blockchains that use the Delegated Proof of Stake consensus protocol, including;

• Steem = 3 seconds blocktime and mining is done in rounds 63 seconds
• Bitshares (BTS) = 1.5 seconds blocktime and 100,000 transactions per second
• Cardano(ADA) = 20 seconds blocktime and 5 - 10minutes transaction time
• Tron (TRX) = 3 seconds blocktime and 1minute transaction time

Conclusion

From the lecture we can all agree that DPoS consensus protocol is correcting the shortcomings of both the PoW and PoS. And this DPoS has proven to be better than most of it's counterparts especially in area of maintaining the decentralized nature of blockchain technology.
PoS is also a great initiative and has helped a lot especially in area of saving energy and making mining less tedious than it used to be when majority were only focused on PoW but notwithstanding, DPoS has also proven to be a better initiative than PoS and I believe this is the main reason most new blockchains are opting for the DPoS consensus protocol.

It was a great lecture and I learnt lot.

Cc: Professor @sapwood

Thanks for reading and I hope I met your expectations