Sharding — what is it and why should the blockchain be divided?
Blockchains suffer from a trio of constraints: scalability, security, and decentralization. Improving one means sacrificing another. To break this triangle, the idea of sharding was proposed — dividing the blockchain into parts.
What is sharding?
Sharding is the division of the entire blockchain network into independent fragments, or shards.
Each shard processes its part of transactions and data, which reduces the load on the entire network.
Example from life: instead of one huge checkout in a supermarket — 100 small checkouts, each serving its own line.
How it works in the blockchain:
Each shard is a mini-blockchain with its own database.
Nodes do not need to store the entire blockchain — only their shard.
The Beacon chain (main chain) coordinates interaction between shards.
Why is sharding needed?
Scalability: the network can process thousands of transactions simultaneously.
Reducing requirements for nodes: there is no need to store and verify the entire history of the network.
Accessibility: more participants can be validators.
What is the difficulty?
Security between shards: they need to not interfere with each other.
Synchronization difficulties: it is necessary to check how data intersects between shards.
Threats of centralization: if one shard is attacked, it can affect the entire network.
Ethereum and sharding
Sharding is part of the scalability of Ethereum 2.0.
Currently, the main focus is on Danksharding and Data Availability, but classical sharding is also an important step.
Conclusion:
Sharding is a way to parallelize the blockchain, like multithreading in a processor. This gives the network a chance to scale without sacrificing decentralization and security — if implemented correctly.
