ADD-IN A-TOOLS ALLOWS SHARING AND MANAGING EXCEL FILE ON LAN, INTERNET

Add-in A-Tools allows sharing and managing Excel file on LAN, internet. Users can open Excel file in server at the same time for editing and saving. Clients connect to server by TCP/IP protocol (not full share folder - Excel's way), server manage connections with restrict users,  setting rights for each user group: read only, edit, limit how many people can open a worksheet,....,When data in spreadsheet is changed then other computers on LAN, internet are updated immediately (after about ~ 1 millisecond).

What is the math? I saw it on excel forum.

And here is my video. I help him by add-in a-tools. Let's see how do add-in a-tools solve it? I thinks it will help him very much.
https://www.youtube.com/watch?v=6elVHYyJ-X8

Thanks