Method of conducting transactions over a network

(57) With the customer (52) who attests by starting a fingerprint identification device (50) by the demand from summary goods or a service provider (60, 62, 64, 66, 68, 70, 72). In the commercial transaction attestation method which attests the commercial transaction between a customer's goods or service provider which receives an authorization code at least through a network through a network from a fingerprint identification device, When a customer's fingerprint is in agreement with the fingerprint memorized in the fingerprint identification device, With the step (104, 106, 108, 110, 112) which generates an authorization code, and the step which receives an authorization code through a network at least from goods or a service provider, when an authorization code is effective at least, The commercial transaction attestation method of having a step (123) which attests a commercial transaction.