Internet Usage Billing
 

hi everybody
this is for an educational institution here we are providing internet
access for students in the normal working hours for free. now i want to give them internet access in the off hours but for nominal charge so if anybody know any solution for charging according to their usage
preferably like prepaid system my management is not ready to spend any extra money for this so please help me
thanks in advanse

IMO any billing software would do or should prove extendible, "prepaid" just is a way of calculating things and pulling the plug when the counter reaches the threshold. If you look down the bottom of this page you'll see related threads under the "Similar Threads" header. Maybe check those out for SW and search Freshmeat and Sourceforge.