ZyZel Communications is upgrading its unified threat management gear for small and midsize businesses with a new line of multi-function boxes that add VPN support and failover.

The USG series (USG stands for unified security gateway) consists of four models, USG 100, 200, 300 and 1000, all of which have their own hardware platform. They replace ZyZel's UTM 5, 35, 70 and 1050 devices, but the company has set no end of life dates for them.

ZyXel says the new equipment is meant to compete directly against similar devices from SonicWall . (Compare UTM products.)

Like the models they replace, USGs include content filtering, intrusion-prevention, antivirus and antispam technology as well as antivirus and IPS services.

The new devices also include IPSec and SSL VPN trunking and high availability via failover to another box in active/passive configuration. The devices support multiple WAN connections and the plan is for all USGs to support 3G wireless cards that can connect to particular service-provider networks. The devices also have an onboard 56Kbps modem for backup.

The USGs include a policy engine that can enforce user restrictions such as allowing instant messaging but not file transfers within IM or blocking peer-to-peer applications or lifting such restrictions during certain hours, say, after the work day.

The devices come with technical support and firmware upgrades at no additional cost for the life of the machines.

All the USG models are available now. The prices are: USG 100, $650; USG 200, $1,000; USG 300, $1,900; USG 1000, $3,400.