Limit users to google services only during office hours

RouterOS General
1

Hi guys, I need to limit staffs to google services (e.g Google hosted Mail, google news, map, etc)
The point is that I know that filtering out traffic based on Destination IP cannot work since google ip changes.
Pls what am I suppose to use?

2

Invest into a web inspection appliance, or roll your own with something like Squid. WebSense does this well, and it’s only $70/IP/year.