The base layer blockchain isn’t too complex of a technology to understand. The base layer is the core chain – the blockchain – that sets the network rules and consus. Any other dApps, protocols, and layer 2 chains allowed to build on the base layer rely upon it to function.
Layer 2 chains are more advanced and harder to grasp conceptually as to how they work and what their function on a blockchain is. The role of a layer 2 blockchain is one of several things:
To increase the blockchains functionality through extension to other blockchains, especially to scale the network.
To improve network experience by easing network congestion, cutting down fees, and speeding up processes.
To add value to the network via tools, services, opportunities, and entertainment.
All layer 2 chains serve one of these purposes. There’s no slowing down in the recent layer 2 evolution over the past 2 years as most networks without a planned layer 2 framework have strained to a point where they could no longer scale or function without any serious issues.
The many variations of layer 2 chains
There are various layer 2 chains to serve a large extent of different requirements:
Nested blockchains – This is a second chain blueprinted off the consensus layer which primarily exists in order to deal with transactions.
Zero-Knowledge Rollups – These are a scalability solution that allow blockchains to validate transactions faster – usually instantly. They also minimize gas fees as they scale, making them one of the biggest assets available to networks that struggle with fees.
Sidechains – While connected to the main blockchain by a bridge, sidechains use their own consensus mechanism to operate. In this way they can add a unique operation, tool, or asset to the network that isn’t accessible on the mainnet.
Shard Chains – These chains split networks into portions or shards. Each shard contains its own independent state, meaning a unique set of account balances, available assets, and smart contracts.
Plasma Chains – Are used to ensure individual token and asset information stored on the network is true.
Optimistic Rollups – Enable smart contracts to run at scale while still being secured by the network.
State Channels – This layer is a two-way communication channel where both parties involved can execute transactions off-chain safely.