RPC Types

The Kademlia protocol consists of four remote procedure calls (RPCs): PING, STORE, FIND_NODE, and FIND_VALUE.

• The PING RPC probes a node to see if it is online.
• The STORE RPC instructs a node to store a [key, value] pair for later retrieval.
• The FIND_NODE RPC takes a 160-bit key as an argument. The recipient of the FIND_NODE RPC returns an (IP address, UDP port, Node ID) tuple for each of the k nodes closest to the target id.
• The FIND_VALUE RPC behaves like FIND_NODE, returning the k nodes closest to the target identifier with one exception – if the RPC recipient has received a STORE for the given key, it returns the stored value.