# Introduction

TRON uses an account model. The address is the unique identifier of an account, and a private key signature is required to operate an account. An account has many attributes, including TRX & token balances, bandwidth, energy, Etc. TRX's and tokens' transferring cost bandwidth, smart contract related operations cost energy. An account can apply to become a super representative candidate and accept votes from other accounts. The account is the basis of all the TRON's activities.

# Account creation

  1. Generate the address and private key using a wallet or explorer. Transfer TRX/TRC10 token to this address to activate the account.

  2. Call the `CreateAccount` contract from an existing account.

Account creation costs only bandwidth. It burns TRX if bandwidth is insufficient.

# Key-pair Generation

Tron's signature algorithm is ECDSA, and the curve used is SECP256K1. A private key is a random number, and the corresponding public key is a point on the elliptic curve. Generating process:

  1. Make a random number `d` as the private key.

  2. Calculate `P = d * G` as the public key. (`G` is the elliptic curve base point)

# Address Format

Use the public key `P` as the input, and use SHA3 get the result `H`. The length of the public key is 64 bytes (SHA3 uses Keccak256). Use the last 20 bytes of `H`, and add a byte of `0x41` in front of it. Do a basecheck (see next paragraph), and the result will be the final address. All addresses start with 'T'.

Basecheck process: first run SHA256 on the address to get `h1`, then run SHA256 on `h1` to get `h2`. Use the first 4 bytes as a checksum, add it to the end of the address (`address||check`). Finally, base58 encode `address||check` to get the final result.

  1. Calculate SHA3 result H with the public key.

  2. Take the last 20 bytes of H and fill a 0x41 byte in front to get the address. (the public key is 64-bytes long. SHA3 uses Keccak256)

  3. Do a basecheck to get the final result. Addresses start with a 'T'. (Basecheck process: calculate SHA256 with the address to get h1; calculate SHA256 with h1 to get h2; add the first 4 bytes of h2 as a checksum to the tail of the address to get address||check, and encode it in base58 to get the final result)

## Character map

ALPHABET = "123456789ABCDEFGHJKLMNPQRSTUVWXYZabcdefghijkmnopqrstuvwxyz"

# Signature

## Steps

  1. Transfer the `rawdata` of the transaction to `byte[]`.

  2. Run SHA256 on the `rawdata`.

  3. Use the private key to sign the result of step 2.

  4. Add the signature to the transaction.

# Algorithm


## Example

Note: The size of the signature result is 65 bytes:

  • `r` = 32 bytes

  • `s` = 32 bytes

  • `v` = 1 byte

  1. Fullnode will verify the signature; it generates an address with the value of `hash`, `r`, `s`, and `v`, then it compares with the address in the transaction.

## Demo