Typed Nodes
While Ethereum only has one node type, Klaytn has multiple node types where each serves different purpose. Here’s a brief description of three main node types:
1. Consensus Node (CN)
CNs decide blocks by running consensus. Only GC members can run CNs, and, thus, form a private network of CNs called Consensus Node Network (CNN). Together with multiple PNs (at least two), a CN forms a Core Cell (CC).
2. Proxy Node (PN)
The primary role of PNs is to protect CNs. As mentioned above, a CC is composed of a single CN and two PNs. In a CC, PNs function as a bridge between a CN and the network outside of CC; they deliver transactions sent from Endpoint Nodes (ENs) to the CN they protect, and propagate blocks (downloaded from the CN) to ENs they are attached to. This provides effective defense to CNs from adversarial attacks such as DDoS.
3. Endpoint Node (EN)
ENs serve as endpoints for Klaytn network handling RPC API requests and processing data sent to and from Service Chains. ENs continuously download blocks and send transactions from/to PNs. ENs form a peer-to-peer network called Endpoint Node Network (ENN). Unlike CNs, anyone can run an EN and join ENN, effectively running his/her own endpoint.