The transfer flow

Transafer flow architecture

1. User enters a request to transfer funds on tanX.

User enters a request to transfer funds using tanX.

2. tanX sends a TransferRequest transaction to Starkware.

tanX sends out a transfer request transaction to the Starkware gateway, using the add_transaction API with the TransferRequest transaction type.

The request includes the following information:

amount	The quantized amount of the asset to transfer.
sender_public_key	The sender’s public Stark key.
sender_vault_id	The sender’s vault id.
receiver_public_key	The receiver’s public Stark key.
receiver_vault_id	The receiver’s vault id.
token	The token to be transferred.
fee_info_user	The maximum fee that the sender is willing to pay for the transaction.
expiration_timestamp	The time after which the request is no longer valid, in hours since the Unix epoch.
nonce	A nonce issued by tanX, to prevent replay attacks.
signature	The sender’s signature.

3. Starkware checks the validity of the request.

Starkware checks the following to validate the transfer request:

• The balance in the sender’s vault is sufficient to fulfill the transaction.

• The maximum fee that the party is willing to pay for the transaction is not less than the actual fee.

• The transaction request has not expired.

• According to the orders tree, the order has not already been fulfilled.

4. Starkware includes the transfer in a batch.

If the transfer request is valid, the transfer is included in a batch to be submitted on-chain along with a validity proof.