layertwo

Layertwo is a term used to describe Layer Two, the second layer in multi-layer architectures such as computer networks and blockchain systems. It is commonly used in technical discourse to distinguish processes that operate above the base layer while depending on its security and data integrity.

In networking, Layer 2 corresponds to the data link layer in the OSI model. It is responsible for transferring data between adjacent network nodes and for controlling access to the physical medium. Layer 2 defines framing, MAC addressing, and error detection, typically through CRCs. Devices such as switches and bridges operate at this layer, forwarding frames based on addresses and, in many deployments, segmenting networks into VLANs. Layer 2 technologies include Ethernet and Wi‑Fi at the link level, and protocols for link establishment, reliability, and local area network topology management.

In blockchain and distributed ledger contexts, Layer 2 refers to networks or protocols built on top of a base Layer 1 blockchain to improve scalability and reduce costs. Layer‑2 systems perform most operations off the main chain and periodically settle results on Layer 1. Common approaches include payment channels and state channels, sidechains, and rollups. These solutions aim to preserve Layer 1 security while increasing throughput and reducing latency, often introducing cross-layer interoperability considerations and tradeoffs in finality and trust assumptions.

The term is domain-dependent: in networking it denotes local data transfer and isolation, while in blockchain it denotes scaling and efficiency enhancements. Related concepts include the OSI model, Layer 1, Layer 3, and specific Layer-2 implementations such as Lightning Network or rollup architectures.