[squid-users] Users Authentication in squid

Hello squid users,

I am confused over here on squid.

i have redhat 9.0 and with the default squid install. It is serving
atleast 70 users. it is working as a transaprent proxy giving caching to
customers.
I want to apply user authentication. Now if customers want to surf
internet then they should use username and password to connect to
internet. I have searched docs for this but didnt find any good one.
so plz tell me how should i configure squid for user authentication.????

i have the default squid rpm install. how should i use any
authentication method in squid rpm ??

if some one could give some url or doc or could little guide to this. It
would be really greatly appreciated.

Thanks,
joel