Receipts states and checks

Receipts are used as single transaction promise of payment. A payment sender creates a receipt and ECDSA signs it, then sends it to a payment receiver. The payment receiver would verify the received receipt and store it to be accumulated with other received receipts in the future.

A list of checks are performed on the received receipts to ensure they are valid. The checks are performed when storing the receipt and when aggregating the receipts into a Receipt Aggregate Voucher (RAV).

Each receipt is wrapped into a State Machine that can be in one of the following states:

• Checking: The receipt is being checked.
• Failed: The receipt has failed a check or validation.
• AwaitingReserve: The receipt has passed all checks and is awaiting escrow reservation.
• Reserved: The receipt has successfully reserved escrow.