The release of firmware Ver. 1.5 for Moxa Technologies' UC-7400 series of embedded computers adds new security features that make UC-7400 suitable as a secure communication gateway. Of particular importance are the IPTables and OpenVPN features, which allow network administrators to set up a firewall, and create a virtual private network over the Internet. This development should come as welcome news to network administrators responsible for managing factory floor and other types of industrial LANs that are connected to the Internet.

IPTables plays the role of gatekeeper by providing network administrators with a straightforward means of setting up firewalls, and the ability to filter out packets sent from specific IP addresses. Another important feature is NAT (Network Address Translation), which is used either to hide the IP addresses of hosts attached to the private LAN, or share a small number of public IPs with a large number of private hosts. For example, most private LANs use private IP addresses of the form 192.168.xxx.xxx. NAT can be configured to allow all of these hosts to access the Internet by sharing one or more public IP addresses. Open VPN is essentially a private LAN extender that provides data encryption with DES, 3DES, and AEC, and requires authorization by members of the VPN.

By adding this capability, Moxa has turned UC-7400 into an economical and easy to use Internet gateway that is suitable for industrial networking applications. All of the new features will be available starting at the beginning of June in Ver. 1.5 of the firmware, which can be downloaded from the Moxa Group website at www.moxa.com. Additional features available with the new firmware include cardbus support for 802.11g wireless LANs, which provides a connection speed of up to 54 Mbps. In addition, the new USB Flash Disk support can combine with UC-7400's CF storage capability to give users greater flexibility for data storage. The PnP (Plug and Play) design of UC-7400's USB host driver makes it easy for users to store and retrieve data from the USB flash disk.

The remaining two features are a new Watch Dog Timer API and a Windows Tool Chain, included for the benefit of UC programmers. Since the vast majority of UC applications require uninterrupted service, a new Watch Dog Timer (WDT) API was added. Programmers can call the WDT API from their own application program to create an automatic reboot capability. In this way, when the application program encounters unexpected errors UC-7420 can reboot automatically to provide uninterrupted service. The Windows Tool Chain is a useful tool for programmers who develop applications for UC-7400 on a Windows platform. The Tool Chain simulates UC-7400's Linux root file system on a Windows PC, making it unnecessary to set up a separate Linux environment for application development.