Our TimeClock Pearl Cloud Solution includes the ability for you to restrict by IP address which workstations have access to your time clock. It's as simple as entering the allowed IP's on your online account on our website.
Our TimeClock Pearl Network Solution would generally only be available to workstations on your local network unless it's installed and being hosted on a workstation/server with a external/public IP, but you can also set restrictions in the database application software hosting TimeClock Pearl.
You can export time clock data in a number of different formats (tab delimited, csv, html, excel, etc) when running timecards and payroll reports, which can potentially be imported, however, there is no direct interface with quickbooks or other accounting software.
Every time clock entry includes a memo field which an employee may enter information. You could potentially have the employees use that field to enter a per diem. The memo field data is not summarized on any reports, but if the data entered is numeric, you can export the information, open it in excel to summarize (total).