avast Network Security Linux
Avast Network Security (includes Core Security)


Manage traffic from one place.
Scan and filter all web (HTTP) and email (POP3, IMAP) traffic on the network.
Feel free to use secure protocols.
HTTPS, POP3S, and IMAPS protocols are supported using certificate resigning.

Key technology:

Keep the performance. The filter is completely transparent to users on the network, so there's no impact on your network performance.

Supported Systems
-CentOS 6 and newer
-Debian 7 and newer

Also works with
-Red Hat Enterprise Linux 6
-Ubuntu LTS 12.4

avast Network Security for Linux