Discrete micropayment protocol based on master-slave payword chain

Using the idea of Payword, the new concept of master-slave payword chain (MSPC) is proposed in this article. MSPC consists of one master payword chain and one slave payword chain. On the basis of MSPC, a new micropayment protocol called discrete micropayment protocol (DMP), is presented in this article. DMP consists of three sub-protocols: registration, payment, and settlement. Both part fairness and non-unit-wise payment can be provided by DMP.