NxFilter is a DNS filtering software. You can filter and monitor Internet activity in your network with NxFilter. It is also capable of detecting and blocking malware and botnet based on DNS packet inspection. It features Active Directory integration, user or group based policy assignment, dual policy setup for work-time and free-time, quota time, phishing protection, block by domain categories, unlimited custom categories, unlimited number of user and group creation, embedded Web server and embedded DB, built-in GUI, built-in clustering, dashboard and report and internationalized domain name support.

AD integration and single sign-on while it's a freeware. Also capable of blocking HTTPS since it's working on DNS level. Providing a remote filtering client and dynamic IP updater. By employing a light weight protocol it can handle several thousands users easily.