Abstract: The invention provides a transaction system in a data network that permits transactions among a buyer, a seller, and a billing device to occur independently. The transaction system may include authorizing tokens, seller cookies and purchase tokens to provide security, efficiency as well as independent operation. The purchase token is issued by the billing device to the buyer for transactions with sellers. The seller may issue a seller cookie to the buyer so that future transactions between the buyer and the seller may occur without interacting with the billing device. The billing device may issue an authorizing token to approve a buyer purchase order and to assure the seller that the buyer account is sufficient to cover prospective purchases. The authorizing token permits the seller to send an invoice to the billing device without being tied to specific transactions with the buyer.