# Encoding

Learn about the encoding formats used on Ethermint.

# Pre-requisite Readings

# Encoding Formats

# Protocol Buffers

The Cosmos Stargate release introduces protobuf as the main encoding format for both client and state serialization. All the EVM module structs that are used for state and clients (transaction messages, genesis, query services, etc) will be implemented as protocol buffer messages.

# Amino

The Cosmos SDK also supports the legacy Amino encoding format for backwards compatibility with previous versions, specially for client encoding. Ethermint will not support Amino in the EVM module once the migration to SDK v0.40 is finalized.

# RLP

Recursive Length Prefix (RLP), is an encoding/decoding algorithm that serializes a message and allows for quick reconstruction of encoded data. Ethermint uses RLP to encode/decode Ethereum messages for JSON-RPC handling to conform messages to the proper Ethereum format. This allows messages to be encoded and decoded in the exact format as Ethereum's.

Each message type defined on the EVM module define the EncodeRLP and DecodeRLP methods which implement the rlp.Encoder and rlp.Decoder interfaces respectively. The RLP encode method is used to sign bytes and transactions in RLPSignBytes and Sign.

# Next

Learn how pending state is handled on Ethermint.