... switched telephone network, amobile telephone network, and the Internet. However, there are already cer-tain services that cross the boundaries between these networks. For example,one can send ... the Merchant agrees with the payment.After the Payment Request message, one or more Payment Exchangemessages can be exchanged between the Consumer and the Payment Han-dler. This type of message ... customer care provider. For example, a merchant can be a merchant cus-tomer care provider at the same time. The protocol describes the content,format and sequences of e- commerce messages that...