address-system.md

.. _protocol-ref-address-transitions:

Platform Address System

:::{attention} Address-based state transitions were enabled in Protocol Version 11. These transitions enable direct operations using Platform addresses without requiring a pre-existing identity for some operations. :::

Overview

Address-based state transitions provide an alternative funding and transfer mechanism using Platform addresses. Unlike identity-signed transactions that require an existing identity with keys, address-based operations can work directly with cryptographic proofs tied to address ownership.

There are six address-based state transition types:

Type	Name	Description
9	Identity Credit Transfer to Addresses	Transfer credits from identity to Platform addresses
10	Identity Create from Addresses	Create identity funded from Platform addresses
11	Identity Top-Up from Addresses	Top up existing identity from Platform addresses
12	Address Funds Transfer	Transfer between Platform addresses
13	Address Funding from Asset Lock	Fund Platform addresses from asset lock
14	Address Credit Withdrawal	Withdraw from Platform addresses to Core

Common Components

Platform Address

Platform addresses are derived from standard Bitcoin/Dash address formats and encoded using bech32m per DIP-0018.

Variant	Type Byte	Size	Description
P2PKH	0xb0	21 bytes	Pay-to-Public-Key-Hash (1 type byte + 20 hash bytes)
P2SH	0x80	21 bytes	Pay-to-Script-Hash (1 type byte + 20 hash bytes)

Encoding:

• Mainnet HRP: dash
• Testnet HRP: tdash (also used for Devnet and Regtest)

Derivation: Standard Bitcoin derivation using Hash160(compressed_pubkey) where Hash160 = RIPEMD160(SHA256(x)).

See the Platform address implementation in rs-dpp.

Address Witness

Witnesses provide cryptographic proof of address ownership. Each input in an address-based transition requires a corresponding witness.

Variant	Size	Fields	Description
P2pkh	65 bytes	signature	Recoverable ECDSA signature
P2sh	Varies	signatures, redeemScript	Multiple signatures with multisig redeem script

P2PKH Verification:

1. Double-SHA256 hash the signable bytes
2. Recover public key from recoverable signature
3. Hash160 the recovered pubkey
4. Compare with address hash

P2SH Multisig Verification:

1. Verify redeem script hashes to address
2. Parse script for threshold (M) and public keys (N)
3. Double-SHA256 hash the signable bytes (reused for all signatures)
4. Match M signatures to N public keys in order

See the witness implementation in rs-dpp.

Fee Strategy

The fee strategy specifies how transaction fees are deducted from inputs or outputs.

Step Type	Type	Size	Description
DeductFromInput	unsigned integer	16 bits	Deduct fee from input at specified index
ReduceOutput	unsigned integer	16 bits	Reduce output amount to cover fee

:::{note} Fee strategy cannot be empty. Maximum steps: 4 (max_address_fee_strategies). No duplicate steps allowed. Steps are processed in sequence until the fee is fully covered. :::

See the fee strategy implementation in rs-dpp.

Common Type Aliases

Type	Definition	Size	Description
AddressNonce	unsigned integer	32 bits	Sequential counter per address (prevents replay)
Credits	unsigned integer	64 bits	Platform credit unit
UserFeeIncrease	unsigned integer	16 bits	User-specified fee multiplier

Platform Address State Transition Details

Identity Credit Transfer to Addresses

Transfer credits from an existing identity to one or more Platform addresses.

Field	Type	Size	Description
identityId	array of bytes	32 bytes	An Identity ID for the identity sending credits
recipientAddresses	map	Varies	Map of destination Platform addresses to credit amounts
nonce	unsigned integer	64 bits	Identity nonce for this transition to prevent replay attacks
userFeeIncrease	unsigned integer	16 bits	Extra fee to prioritize processing if the mempool is full
signaturePublicKeyId	unsigned integer	32 bits	The ID of the public key used to sign the state transition
signature	array of bytes	65 bytes	Signature of state transition data

:::{note} Minimum recipients: 1. Maximum recipients: max_address_outputs. Minimum per recipient: 500,000 credits. Fee: 500,000 credits base + 6,000,000 credits per recipient (example: 1 recipient = 6,500,000 credits minimum fee). :::

See the implementation in rs-dpp.

Identity Create from Addresses

Create a new identity funded from Platform address balances.

Field	Type	Size	Description
publicKeys	array of keys	Varies	Public key(s) for the new identity (1-6 keys)
inputs	map	Varies	Map of source Platform addresses to (nonce, credits) pairs
output	tuple	Varies	(Optional) Change output as (Platform address, credits)
feeStrategy	array	Varies	Fee deduction strategy
userFeeIncrease	unsigned integer	16 bits	Extra fee to prioritize processing if the mempool is full
inputWitnesses	array	Varies	Address witnesses for each input

:::{note} Constraints: Minimum inputs: 1. Maximum inputs: max_address_inputs. Maximum public keys: 6. Minimum per input: 100,000 credits. Minimum output: 500,000 credits. Minimum funding: input sum ≥ output sum + 200,000 credits.

Cost: Base cost 2,000,000 + 6,500,000 per key. Example: 2 keys = 15,000,000 credits. :::

See the implementation in rs-dpp.

Identity Top-Up from Addresses

Add credits to an existing identity from Platform address balances.

Field	Type	Size	Description
identityId	array of bytes	32 bytes	An Identity ID for the identity receiving the top-up
inputs	map	Varies	Map of source Platform addresses to (nonce, credits) pairs
output	tuple	Varies	(Optional) Change output as (Platform address, credits)
feeStrategy	array	Varies	Fee deduction strategy
userFeeIncrease	unsigned integer	16 bits	Extra fee to prioritize processing if the mempool is full
inputWitnesses	array	Varies	Address witnesses for each input

:::{note} Constraints: Minimum inputs: 1. Maximum inputs: max_address_inputs. Minimum per input: 100,000 credits. Minimum output: 500,000 credits. Minimum top-up: input sum ≥ output sum + 200,000 credits.

Fee: Base top-up cost: 500,000 credits. :::

See the implementation in rs-dpp.

Address Funds Transfer

Transfer credits between Platform addresses.

Field	Type	Size	Description
inputs	map	Varies	Map of source Platform addresses to (nonce, credits) pairs
outputs	map	Varies	Map of destination Platform addresses to credit amounts
feeStrategy	array	Varies	Fee deduction strategy
userFeeIncrease	unsigned integer	16 bits	Extra fee to prioritize processing if the mempool is full
inputWitnesses	array	Varies	Address witnesses for each input

:::{important} Unlike other address transitions, fund transfers enforce strict balance preservation. The total input amount must exactly equal the total output amount (before fee deduction). :::

:::{note} Constraints: Minimum inputs: 1. Maximum inputs: max_address_inputs. Minimum outputs: 1. Maximum outputs: max_address_outputs. Minimum per input: 100,000 credits. Minimum per output: 500,000 credits. No output can also be an input.

Fee: 500,000 credits per input + 6,000,000 credits per output. :::

See the implementation in rs-dpp.

Address Funding from Asset Lock

Fund Platform addresses from a Core chain asset lock special transaction.

Field	Type	Size	Description
assetLockProof	object	Varies	Asset lock proof proving locked funds (Instant or Chain)
inputs	map	Varies	(Optional) Map of existing Platform addresses to combine
outputs	map	Varies	Map of destination addresses to credits (one must be None for remainder)
feeStrategy	array	Varies	Fee deduction strategy
userFeeIncrease	unsigned integer	16 bits	Extra fee to prioritize processing if the mempool is full
signature	array of bytes	65 bytes	Asset lock signature
inputWitnesses	array	Varies	Address witnesses for any existing address inputs

This transition uses dual signing: an asset lock signature proves ownership of locked funds, and address witnesses prove ownership of any existing address inputs (if combining funds).

:::{important} Exactly one output must have a None value. This remainder output receives whatever funds remain after explicit outputs and fees are satisfied, ensuring full consumption of the asset lock. :::

:::{note} Constraints: Minimum outputs: 1. Maximum inputs: max_address_inputs. Maximum outputs: max_address_outputs. Minimum per input: 100,000 credits. Minimum per explicit output: 500,000 credits. No output can also be an input. :::

See the implementation in rs-dpp.

Address Credit Withdrawal

Withdraw credits from Platform addresses back to the Core chain.

Field	Type	Size	Description
inputs	map	Varies	Map of source Platform addresses to (nonce, credits) pairs
output	tuple	Varies	(Optional) Change output as (Platform address, credits)
feeStrategy	array	Varies	Fee deduction strategy
coreFeePerByte	unsigned integer	32 bits	Core transaction fee per byte (must be a Fibonacci number ≥ 1)
pooling	unsigned integer	8 bits	Pooling mode: 0 = Never (required), 1 = IfAvailable, 2 = Standard
outputScript	array of bytes	Varies	Core chain destination script (P2PKH or P2SH only)
userFeeIncrease	unsigned integer	16 bits	Extra fee to prioritize processing if the mempool is full
inputWitnesses	array	Varies	Address witnesses for each input

:::{note} Constraints: Minimum inputs: 1. Maximum inputs: max_address_inputs. Minimum per input: 100,000 credits. Minimum output: 500,000 credits. Pooling must be Never (others not yet implemented). Output script must be P2PKH or P2SH.

Fee: 400,000,000 credits. Withdrawal fees are significantly higher due to the complexity and finality of moving funds back to the Core chain. :::

See the implementation in rs-dpp.

Address State Transition Signing

Address-based state transitions use different signing methods depending on the type. See the state transition signing page for full signing details.

Category	Transitions	Signer
Identity-signed	Type 9	Existing identity key
Address-witness-signed	Types 10, 11, 12, 14	Address owner(s)
Dual (Asset lock + Address)	Type 13	Asset lock owner + optional address owners

Related Constants

For complete constants reference, see Protocol Constants.

Constant	Value	Size	Description
min_input_amount	100,000 credits	64 bits	Minimum per input
min_output_amount	500,000 credits	64 bits	Minimum per output
min_identity_funding_amount	200,000 credits	64 bits	Minimum for identity creation/top-up
max_address_inputs	16	16 bits	Maximum inputs per transition (Protocol Version 11+)
max_address_outputs	128	16 bits	Maximum outputs per transition (Protocol Version 11+)
max_address_fee_strategies	4	16 bits	Maximum fee strategy steps

For related identity operations, see Identity and State Transitions.