Product: TS100 Secure Device ServerManufacturer: Cyclades CorporationURL: www.cyclades.comRequirements: None

The TS100 is a compact Linux-based serial server that enables communication with serial devices over a TCP/IP network. It comes equipped with enough hardware and software to be used for many other general purpose applications, making it a cost-effective platform. Highlights are a software-configurable RS-232/RS-485 serial interface, a complete development environment and excellent technical support.

Our company's flagship product, e-Guardian, is a distributed monitoring system that hooks into various brands of mission-critical devices, mostly serial-based, and monitors them for data and alarm events. We therefore needed a low-cost, reliable hardware platform to connect to the devices that had enough resources to deploy our data collection software. Our previous choice of serial servers had limited resources and some reliability issues that were beginning to concern us. In addition, our server software is Linux-based, so we were looking for a Linux-compatible data acquisition platform to maximize our code re-use.

The TS100 from Cyclades Corporation is a fairly recent product, but it uses technology from the proven terminal server (TS) series, which is marketed for console management and remote access. Essentially, it is a scaled down single-port version that uses essentially the same hardware and software as the upper-end multiport models (4, 8, 16, 32, and 48 ports). In addition, it has a few new key features of its own.

The TS100 is a compact unit--the size of a deck of playing cards--but packs a mighty punch. It sports a 50MHz MPC855T PowerPC processor, the same one used in its higher-end cousins. With 16MB of RAM and 4MB of Flash, this is more than adequate computing power for most embedded applications today. The interfaces include a 10/100BT auto-sensing network controller and a single serial port that supports both the RS-232 and RS-485 (full and half duplex) protocols. This feature is important for the industrial automation and control field where a large percentage of gear is based on RS-485 communication, which allows for daisy chaining of devices and longer serial cable runs.

A software switch controls the communication mode on the serial port rather than the hardware jumper sometimes found on other serial servers. This switch allows application code to specify the communication mode on the fly, without requiring a physical visit to the unit. The other nice thing about the TS100 is you can connect to the RS-485 interface using either a standard DB-9 connector or a terminal block. This is particularly useful when connecting to non-IT related physical gear. The TS100 can be powered through various options, including the -48VDC method common in telco environments. Or it can connect using the Ethernet port with an add-on Power-over-Ethernet module.

My only nitpick with the hardware is the enclosure could be more solid and robust, but the unit has certainly proven itself in the field. Also, the small size of the unit sometimes makes it awkward to position and mount in a 19" data center rack.

Cyclades exacts maximum leverage with open-source software, and the TS100 comes a full-fledged Linux distribution (Hardhat Linux) from MontaVista Software, which is based on the 2.4.X kernel. Out-of-the-box software includes OpenSSL, OpenSSH, RADIUS dial-in authentication and IP packet filtering for security. Other useful management applications include an embedded SSL-capable web server, the UCD SNMP suite, DHCP (server and client) and the invaluable BusyBox collection of utilities. In addition to that, the software suite includes console management software to access serial data over a TCP/IP network, including off-line data buffering and serial port sniffing.

A development kit is available to deploy custom applications on the TS100. The kit consists of the familiar GCC compiler tool chain that can be used on x86-based Linux hosts. Java is not available from Cyclades as far as I know, but MontaVista provides a version of the IBM VisualAge Micro Edition. One minor annoyance is the TS100 does not yet support a Flash filesystem, such as JFFS2, so any custom applications have to be bundled with the firmware consisting of the Linux kernel and a RAM disk image. However, firmware upgrades are fairly easy via popular protocols such SCP, FTP and TFTP. Documentation is good, and technical support is outstanding.

The TS100 single-port device server from Cyclades is an excellent platform for networking serial devices. It is based on a powerful PowerPC architecture and has enough horsepower to host a variety of sophisticated applications. Thoughtful features like the software-controlled RS-232/RS-485 interface and Power-over-Ethernet make it convenient to connect to other devices for monitoring and control applications. The included Linux distribution is mature and comes with a complete development environment for deploying custom applications. The addition of a Flash filesystem would make this winner even more appealing. In a large and complex application--such as our distributed monitoring system, e-Guardian--the TS100 has proven itself in the field.

Ujwal S. Sathyam, Ph.D. is the Director of Engineering at NetBrowser Communications, Inc., a leading provider of distributed monitoring systems for mission critical physical infrastructure.