Assalamualaikum,
Hello and welcome fellow steemians on my homework post for Professor @sapwood on different types of consensus mechanisms. So, let's get started.

Question 1 : What is the difference between PoW & PoS ? Advantages & Disadvantages? Which one is better in scaling Capacity ? Examples ?

First we have to understand what is PoW and PoS.

PoW :

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PoW stands for Proof of Work. It is a mechanism which requires a huge amount of energy for mining. It is basically created to solve the problem of spam email and it is also used in mining of newly tokens. PoW is a necessity of Blockchain for the addition of new blocks.

PoS :

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PoS stands for Proof of Stake. It is first introduced back in 2011. It is like an alternative of Proof of work. It is a system that depends on an individual to mine on the basis of quantity of coin he has. There are many improvements in PoS and there's a low ratio of risk in PoS as compare to PoW in terms of an attack on network.

DIFFERENCE BETWEEN PoW AND PoS :

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These are some major differences between PoW and PoS.

• In Proof of work minig is depend upon the computational energy or power while in Proof of Stake it depends upon the quantity of holdings an individual have.

• In Pow, a miners get a reward on the basis of work he does. In other words PoW need any kind of proof that the work is occurred while on the other hand in PoS the individual is selected on the basis of how many holdings he has for the determination of next block.

• Proof of work system consume less energy and are low in cost, but they are more proven. On the other hand PoS is more costly but they are less proven than proof of work.

• In Proof of work, it is required for hackers to have 51% of computation power to link or add to malicious block where's in Pos hackers would have 51% of digital currency which is not possible at all.

• In Proof of work system the initial investment is to buy a mining hardware while in Proof of Stake the initial investment is to buy a coin and improve your reputation.

• In Proof of work, for the addition of each block in a chain miners have to solve complex puzzles by the use of their computation power while in Proof of Stake there is no need of solving any complex puzzle because an algorithm selected the creator on the basis of number of stakes he has.

Advantages of PoW :

These are some advantages of proof of work.

• Proof of work is very good in terms of blocking the spammers as they are created to solve the problem of spamming.

• Proof of work provides security to the whole network which is primary for any Blockchain.

• Proof of work also influences the owners of small fractions of crypto currencies and reward miners in the form of transaction fees and also in block.

Disadvantages of PoW :

These are some disadvantages of proof of work.

• The major disadvantage of proof of work is that this system waste so much energy which is not good for it. This also results in the uplifting of PoS.

• Proof of work only provides security if the network is large but in case of small network there is a chance that hackers can attack the network's computational power.

Advantages of PoS :

These are some advantages of PoS.

• Proof of Stake has good energy efficiency as compare to proof of work. A miner does not have to waste large amount of energy for mining of blocks.

• Proof of Stake system is easy to access. Their is no need of a costly or special hardware for mining the new blocks.

• Proof of Stake helps to secure the network properly. It has also less ratio of risk as compare to PoW in terms of attacking the network.

Disadvantages of PoS :

These are some disadvantages of PoS.

• One of the major disadvantage of Proof of Stake system is that they are costly and it's security is less proven as compare to the proof of work. An individual can easily harm the network.

• In Proof of Stake system, it is impossible to sold the coin if it is stacked once, until a stimpulated time period has passed.

Which one is better in scaling capacity?

As long as I studied and learned about PoW and PoS, Proof of Stake is more reliable than proof of work in scaling capacity. The reason is that Proof of Stake system has a speed of very high transaction that manages thousands of transactions per second and it is not depends on time. On the other hand, proof of work system has some limits in scaling capacity as it transact 64 transactions per second only.

EXAMPLES :

PoW :

Bitcoin( BTC ), Ehereum ( ETH ) and Dogecoin ( DOGE )are some examples of Proof of Work.

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PoS :

Cardano ( ADA ) and Solana ( SOL ) are the examples of Proof of Stake.

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CONCLUSION :

Proof of work is basically created to solve the problem of spam email. In Proof of work, miners have to solve complex problems depends upon the computation power while on the other hand Proof of Stake system allows miners to mine on the basis of quantity of coins they have. Proof of work system. Proof of work system consumes less energy and they are low in cost while proof of Stake system is high energy efficient and very expensive. Proof of Stake is more reliable than proof of work as it manages thousands of transactions per second.

CC

@sapwood