An assignment in it, An assignment in IT. I need to write 3

An assignment in IT. I need to write 3 pages about Transaction Payment System . In this 3 pages, I need to find an problem about it and write the solution of it. I found some articles which could be helpful.
http://www.grin.com/en/e-book/68140/problems-and-solutions-to-transaction-processing-systems
You can click the “Read the ebook” . There is 3 pages free to read which is helpful enough.
https://www.coursehero.com/file/12636314/4-HSC-Option-1-Transaction-Processing-SystemsPDF/