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

Introduction

The process of validating transactions during the mining process of cryptocurrency has some principles and techniques used by the miners. To be able to confidently certify a transaction and add it to the block, there has to be an agreement among the different miners in a form of consensus. Different block chains adopt different protocols to reach this consensus among their miners. This is what this task by @sapwood contained as such i will be explaining a some of this consensus protocols in the following sections.

What is the difference between PoW & PoS?

Both proof of work (PoW) and proof of stake (PoS) are protocols used to reach a consensus adopted by some blockchains. Yet, they are not the same and do not have the some mode of operation.

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PoW consensus protocol assembles transactions and leaves room for miners to access these transactions for validation. These miners can thus randomly pick up these transactions and work on them. The transactions that receives the highest amount of validation and posses the longest chains are then certified as being secure and are added to the blocks or ledgers. PoW does not depend on any third party. It was developed by bitcoin founder Satoshi Nakamoto.

While

In PoS protocol there some qualifications spelt out for a miner to be allowed or chosen to take part in the process of validating transactions for mining. Here, transactions are allocated and assign to miners for validation based on the quantity of stake they posses. The higher the portion of defined stake owned, the higher the chances of being assigned transactions for validation. PoS is a protocol that Scott Nadal and Sunny King invented in the year 2012.

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Some of the differences the exist between them are given in the table below

PoW	PoS
Transactions here are dropped into an unconfirmed pool where miners can free access them and pick them up for validation	PoS protocol assigns these transactions to miners. Not all miners have freedom to pick up transactions for validation
The system is highly decentralized as no one is in charge of distributing the transactions but anyone can access them. It more random and makes use of a mining rig.	There is some form of control and it tends to be centralized. It uses a more deterministic model and does not support mining rig.
There is active competition among miners	There is no competition. Validator's are chosen
The first successful miner earns the rewards	The rewards does not go to the first successful miner but rather the transaction fee goes to the block creator.
It more energy inefficient though there is greater freedom	it is more energy efficient and has less freedom of selection.
In PoW, a miner is more concerned about investing in hardware. That is PoW depends on computer's processing power	In PoS, a validator's concern is his investment in a blockchain's native coin
The stake controlled by a particular miner is not considered as a requirement for participation in the mining process	Attention is given to how much stake either in ownership of native coin or voting power a miner posses before being assigned transactions for verification and validation.

Advantages & Disadvantages of PoW and PoS

Advantages of PoW

• It allows for greater participation of more miners in the process and gives wider opportunities to miners.
• It encourages more security
• It ensures total decentralization and freedom thus having less limitations for miners.
• It promotes better intellectual property on the part of miners and makes it possible for the best hands to participate in solving the various puzzles without the hindrance of having to hold high stakes.

Disadvantages of PoW

• It does not allow for efficiency in energy usage.
• It involves great time wasting
• It does not allow for high scaling capacity as one transaction may be picked simultaneously by more than one miner thereby reducing its productivity. Repetitions are common.

Advantages of PoS

• It is more energy efficient
• It gives room for high scaling capacity
• It helps to improve the price dynamics of the coins or tokens.
• It gives room for better reward system.
• It is more attractive to stakeholders

Disadvantages of PoS

• It is less secure than PoW
• It is more centralized
• It does not give room for high intellectual expression on the part of the miners as miners use their stakes to earn mining rights.

Which one is better in scaling Capacity?

PoS is better in scaling capacity than PoW. PoS allows for more more tasks to be assigned out to miners faster. Also, with the absence of mining rig, there is no chance of simultaneously validation by more than one miner at a time. In this way, PoS protocol allows for more transactions to be handled at a particular time.

Examples of PoW and Pos

PoW

• Bitcoin
• Litecoin
• Ethereum
• Dogecoin
• Monero
• Dash

PoS

• DASH
• NEO
• TEZOS
• Cardamom
• Cosmos
• Tezos
• Alogorand
• Waves
• Qtum
• Lisk
• Ardor

Conclusion

It is simply a necessity in the crypto sector that a consensus be reached on the transactions to be entered into the blocks. However, different tokens hold the exclusive rights to decide which of the consensus protocols to adopt. The different protocols have their pros and cons and as such it is a matter of which best suits the desires and aims of a currency. These protocols also dictate the method of participation of miners.
This has been a really lovely lesson by Prof. @sapwood