1- Can I authenticate my users by Active Directory ? I have 3 Domain Controller servers where my domain is 'intern.it' (MS DNS) I have another domain, on the external side (extern.it) , which I use to publish web services and SMTP traffic (Linux srv, Bind9 package) Clients use MS internal dns, while Squid uses extern dns. Squid (2.7 Stable3) and Bind services are on the same server. 2- In order to integrating Squid authentication to Active Directory, can keep these 2 domains as now (divided and independent) ? I read that, for creating this system, I have to insert my squid into domain, by SAMBA package, but my purpose is keeping same behaviour and environment. Riccardo