Cardano

UTXO model

Cardano is a proof of stake blockchain that uses a UTXO based ledger. This page explains Cardano specific behavior when using IBM Digital Asset Haven wallets. Cardano uses a UTXO model similar to Bitcoin. The main difference is that a single UTXO can hold multiple assets at once.

Multi asset UTXOs

Each UTXO can contain:

ADA (the native currency)
One or more native tokens
NFTs

When a transaction delivers several assets to your address, they are stored together in a single UTXO.

Minimum UTXO value

Cardano requires a minimum amount of ADA in each UTXO. This minimum increases as more assets are included in the UTXO.

UTXO contents	Approximate minimum ADA
ADA only	Approximately 1 ADA
ADA with one token	Approximately 1.5 ADA
ADA with many tokens	Higher, depending on quantity

The more assets a UTXO holds, the higher the minimum ADA requirement. Ensure that your wallet maintains enough ADA to cover the holding cost for all assets.

Transfers

Use the Transfer Asset endpoint for Cardano transfers.

Native ADA: Use kind: Native and specify the amount in lovelace. One ADA equals 1,000,000 lovelace.
Native tokens: Use the appropriate token kind and include the policy ID and asset name.

Single asset transfers: IBM Digital Asset Haven processes one asset per transfer. If you need to send multiple assets in a single transaction, use the Broadcast endpoint to create and submit a custom transaction.

Webhooks

When a multi asset UTXO is received, IBM Digital Asset Haven generates one webhook per asset contained in the UTXO. A single transaction may therefore trigger multiple webhook notifications.