how to restrict Internet Data download limit to 15000MB on the network

gus

The current Internet Plan we're using is 15000MB Data Download Limit per month with access-link 1024kbps/512kbps. The problem is at the end of every month we get access fees for going over the download limit. I want to create a rule that will automatically drop or give an error for any internet users on the local domain downloading if the 15000MB is already being used or reached.

I'm using a CentOS version 5 with Squid proxy configured, local network: 192.168.x.x/24

I've add the following lines in blue to my squid.conf. I wonder if it's gona work. Any other helpful tips on how to do this? thanks for your help

#vi /etc/squid/squid.conf

# Adapt to list your (internal) IP networks from where browsing

# should be allowed

acl gus.local src 192.168.x.x/24

# Recommended minimum Access Permission configuration:

# Not allow more than 15000Mb download

reply_body_max_size 15000 Mb gus.local

#where browsing is allowed

http_access allow gus.local

:qw

# /etc/init.d/squid restart