Is there any free program for accounting Internet traffic in the local network?

Question

Computer networks

There was a need to monitor (block) user traffic. As usual, there is no money for paid programs, so I'm looking for a free alternative. Maybe someone already uses something similar and will tell you which program to try?
Taking indicators from the modem is not an option, because. modem is old.
Ps I tried to google, but either I run into software from 2006-2010, or this software is simply doubtful.

Answer 1

Any free billing.
nodeny-plus.com.ua - basically has the necessary functions, free in this version
bgbilling.ru/index.shtml - a test license is enough for a share.
If you are ready to spend a little money, any MikroTik router has the necessary functionality out of the box.
It is also possible through a proxy with control, then Squid + muzzles.

Answer 2

You can hardly do without a proxy, the options are:
Squid + sams or squid + sarg.