Abstract: There are many virtual payment systems available to
conduct micropayments. It is essential that the protocols satisfy the
highest standards of correctness. This paper examines the Netpay
Protocol [3], provide its formalization as automata model, and prove
two important correctness properties, namely absence of deadlock
and validity of an ecoin during the execution of the protocol. This
paper assumes a cooperative customer and will prove that the
protocol is executing according to its description.