Degree Name

Master of Science (Hons.)


School of Information Technology and Computer Science


There are many challenges to make micropayment systems on the Internet work as reliably, safely and efficiently as they need to. I have studied many of these problems, and seen how different researchers have tried to solve the challenges. A summary of many of these problems and suggested solutions are presented in this thesis. A new micropayments system is presented, based on Merkle's authentication tree and Wintemitz's one-time signatures. The scheme can add efficiency and flexibility to a range of existing micropayment schemes based on hash chains. Unlike earlier system, hash chains can be made relatively short, since the computational cost of authenticating a new hash chain is made small.