Supplies the system and services to establish the back-office infrastructure for businesses. Major aspects include: the processing of secure transactions, the developing and managing of customer relationships, the collecting of payment, and the delivering of products or services over the Web. A CSP may provide the following services: buyer authentication, order taking, details of what is for sale in an electronic offer, validation, payment processing (via traditional credit card payment processors), and generation of electronic receipts. Fulfillment may be made of electronic goods or physical goods.