I used to be an assistant manager for the One-Stop (T&S) chain of stores in the UK. They upgraded from the old fashioned tills to computers acting as EPOS terminals 9also known as PcPOS) in the year 2000. The terminals were each run by a seperate computer, and the back office had a computer with the office programs/cashing up functions. They were linked by a LAN together, so they could communicate when cashing up, and searching the product database etc. There was an ISDN connection, which was plugged into a router and shared between all three terminals for stuff like card authorising, and VPN (for when head office needed to log onto our machines remotely).
The tills used: Pentium 3, Windows NT, running some software called Riva pc2till or something like that.
The back office pc used: Riva Backoffice also running windows NT on a pentium 3 system.
The whole Riva thing is a collection of software for small to large chains of stores it even comes with in built network functions too for upgrading product database etc. I have searched the net for info on this but there seems to be not a lot out there.
Anyway the best I can do is that you have a look out for the Riva brand. They may have changed names now but thats all i know
-Kan3