Like most Unified Threat Management (UTM) products, the Astaro Security Gateway offers a mix of firewall, email, web filtering and other security tools. Unlike the others, though, it is available both as a hardware appliance and as software – even as a ready-to-run virtual appliance.

Astaro is the first security vendor to offer its product this way, complete with supporting security-hardened Linux OS, pre-installed as a VMWare virtual machine.

We downloaded the VM version and ran it using VMWare Workstation on a Fedora Core host, although you can use the free VMWare Player and VMWare Server products or the VMWare Infrastructure 3 solution.

You end up with a virtual machine configured with 256MB of memory, a 30GB hard disk and two Ethernet adapters. Not a powerful platform but sufficient for small business needs and it’s easy to add more, with centralised management an optional extra.

With a virtual appliance there is no need for special hardware. We also found the Astaro virtual machine quick to deploy, taking about a minute to boot on our test PC, after which everything is managed via a web interface, identical to that on ‘real’ Astaro appliances.

Functionality is the same too, with a stateful inspection firewall combined with HTTP, DNS, SMTP, Pop3 and other proxies to support the other options, such as content filtering and anti-spyware scanning.

Two independent scanning engines (Kaspersky and Clam) provide virus protection, scanning both email and web downloads, with nine methods of identifying spam also available. The Security Gateway can also act as a virtual private network server.

This is impressive but very little is done for you and we found the appliance version poorly documented.