In a lengthy Twitter thread, Vitalik Buterin, the co-founder of Ethereum said that sharding basd proof of stake algorithms will make blockchains 1000x more efficient.
9. Blockchains of the future with proof of stake and sharding will be thousands of times more efficient, and so the efficiency sacrifices of putting things on a chain will become more and more acceptable.
— Vitalik Non-giver of Ether (@VitalikButerin) December 10, 2018
Sharding In Blockchain
Sharding is a concept that’s widely used in databases, to make them more efficient. A shard is a horizontal portion of a database, with each shard stored in a separate server instance. This spreads the load and makes the database more efficient.
In case of the blockchain, each node will have only a part of the data on the blockchain, and not the entire information, when sharding is implemented. Nodes that maintain a shard maintain information only on that shard in a shared manner, so within a shard, the decentralization is still maintained. However, each node doesn’t load the information on the entire blockchain, thus helping in scalability.
The pos algorithm has specific, designated nodes that take transaction validation responsibility. These nodes are called ‘stakers’, for, they stake some of their crypto tokens for transaction validation. Upon successfully validating a transaction, the stakes may earn part or whole of the transaction fees. The more crypto token a staker stake for transaction validation purpose, and the longer the duration of the stake, the higher is the number of transactions the node gets to validate.
Wider adoption of sharding requires the blockchain and crypto developers to work on an important area. While communication between nodes within a shard is smooth, inter-shard communication is currently not easy and requires the development of a separate protocol. Addressing this key requirement will potentially result in a wider adoption of sharding, and that’ll help blockchain more scalable with higher transaction throughput.
PoS In Ethereum
Earlier Vitalik had said:
“ It's really important to mention that validators are super-frequently reshuffled between shards (possibly even once per block), so it's actually quite hard to “target” one specific shard for an attack. This is a large part of where sharding's at least theoretical success in breaking the trilemma comes from.”
Sharding is a smart approach to tackling the blockchain scalability problem. However, it’s not without its drawbacks.
Because of its structure, it’s easier to compromise a shard within the system. This is one of the driving reasons behind Ethereum’s switch to Proof Of Stake. Proof Of Stake also helps mitigate this security vulnerability that comes with Sharding.