Recursive Length Prefix (RLP)
Web3 / infrastructure applications
Recursive Length Prefix is the standardized encoding scheme used throughout Ethereum to serialize and structure nested arrays of binary data into a compact byte format. RLP recursively encodes data structures by prefixing each element with its length, allowing efficient transmission and storage of complex data like transactions, blocks, and state trie nodes. The encoding is deterministic and reversible, meaning the same data always produces identical RLP output and can be unambiguously decoded back to its original form. RLP's simplicity and efficiency made it the foundational serialization method for Ethereum's entire protocol stack, from transaction broadcasting to blockchain storage. Example: When an Ethereum transaction is broadcast across the network, its fields (nonce, gas price, gas limit, recipient, value, data, signature) are first serialized using RLP encoding before being transmitted as hex-encoded bytes in network packets or stored in mempool databases. Why it matters for blockchain infrastructure: RLP standardization ensures all Ethereum nodes can reliably encode, decode, and validate data consistently across the network. This uniform serialization format is critical for achieving consensus and enabling interoperability between different client implementations.
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