Disclaimer
The Author of this posting offers the information contained within this posting without consideration and with the reader's understanding that there's no implied or expressed suitability or fitness for any purpose. Information provided is for informational purposes only and should not be construed as rendering professional advice of any kind. Usage of this posting's information is solely at reader's own risk.
Liability Disclaimer
In no event shall Author be liable for any damages whatsoever (including, without limitation, damages for loss of use, data or profit) arising out of the use or inability to use the posting's information even if Author has been advised of the possibility of such damage.
Posting
Routers don't have feature to limit bandwidth by some to some cumulative amount.
What you might be able to do is use embedded scripting, monitor usage from 6 AM to 8 PM, and as it approaches your cumulative limit, add (via the embedded script) a policer to try to avoid hitting your cap. The embedded script could set a policy, as the cap is about to be reached, to drop all further packets. It could also have tiers allowed policed bandwidths, which slow egress rates as cap is approached.
