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Linux-powered device servers offer graphical interfaces

Jan 31, 2006 — by LinuxDevices Staff — from the LinuxDevices Archive — 1 views

Opengear is shipping a pair of Linux-based device servers said to offer secure access to a variety of devices. The dual-port SD4002 and eight-port SD4008 can securely tunnel serial, RDP, VNC, HTTP, or telnet sessions from devices with text-based, graphical, or web-based interfaces, Opengear says.

(Click for larger view of SD-4000-series device servers)

According to Opengear, the SD4000-series devices offer basic serial-over-IP capabilities found in traditional device servers. However, they additionally offer VNC-, HTTP-, and RDP-over-IP capabilities, based on port-forwarding to machines connected to the local LAN. This feature allows control engineers to remotely operate PCs, Windows-powered machines, and browser-controlled appliances “as if they were sitting in front of their office computer,” the company claims. Opengear debuted its RDP and VNC tunneling software in its CM4000-series devices launched last November.

The SD4008 provides eight software-configurable serial ports

The SD4002 supports DIN-rail mounting
(Click to enlarge)

Opengear says its RD4000-series devices are more secure than traditional serial device servers, because remote communications are protected by 128-bit AES encryption. It calls SD-4000 security especially useful for protecting devices based on embedded Windows operating systems, which it says can fall prey to the same viruses, trojans, and worms that plague desktop Windows OSes.

Opengear also touts the SD-4000-series devices' secure web-based management interface, which it says can be accessed via network or dial-up connections. The interface lets users configure the appliance, set security levels, and access the ports — even supporting multiple users per port, the company says. Advanced users can also interface directly at the command line with the embedded Linux kernel, the company says.

The SD4000-series devices additionally support some management via SNMP (simple network management protocol), with support for IPMI (intelligent platform management interface) and other remote management protocols pending further industry adoption, Opengear says.

Additional features include access logging via syslog to NFS- or CIFS-mounted shares, and filtering and alerting capabilities. The devices also support Flash firmware upgrades, using firmware images distributed at no charge via FTP.

Devices supported by the SD4000-series gadgets include switches and firewalls, and security and power switch appliances, as well as serial-interfaced industrial control devices typically found in refineries, factories, utilities, processing plants, and health clinics, Opengear says.

The SD4002 has three ports, including one RS-232 serial port on a DB9 connector, one software-selectable RS-232/422/485 serial port with surge protection on a DB9 connector, and one 10/100 Ethernet port on an RJ-45 connector. It measures 3.9 x 2.8 x 1.0 inches. It can be wall mounted or attached to DIN rails.

The SD4008 has eight software-selectable RS-232/422/485 serial ports on RJ-45 connectors, along with one RS-232 local console or modem port on a DB9 connector, and one 10/100 Ethernet port on an RJ-45 connector. It measures 8.2 x 4.9 x 1.2 inches. It can be wall- or desktop-mounted.

The SD4000-series devices boot embedded Linux from 8MB of Flash, and have 16MB of SDRAM. They are based on a Micrel KS8695P SoC (system-on-chip). The KS8695P is based on an ARM9 core clocked at 166MHz. It has a memory management unit (MMU), and integrates a 5-port managed switch, along with a 33MHz PCI bridge.

Bob Waldie mini-interview

Snapgear CEO Bob Waldie said, “If you look inside [traditional serial device servers], they're limited in terms of processing power. If you're going to do lots of ssh tunnels, and compression [for dial-up access], you need a fair bit of processing power. Our device servers go a bit upmarket in terms of grunt.”

Asked what he thought of Avocent's $90M acquisition of Cyclades, Waldie replied, “We're trying to work out what the impact is. Avocent's a really well-established, well-run company, but its technologies are pretty old hat. KVM's are lame old dogs, really. Cyclades, on the other hand, is a really exciting company. They use a lot of open source software, and sell direct. So, [the acquisition looks like] Avocent's taking Viagra. They'll be dangerous in the short term, but I'm not sure what the long-term effects may be.”

Waldie adds that he appreciates seeing an open source company such as Cyclades succeed. “Cyclades has been a good open source citizen,” Waldie notes.

Waldie previously founded Moreton Bay, later known as Snapgear. Moreton Bay/Snapgear was acquired twice, once by erstwhile embedded Linux development house Lineo, and then later by security appliance vendor CyberGuard.

Waldie says that if Opengear succeeds, it, too, will likely attract M&A (merger and acquisition) offers. “The reality is that 50 percent of the time, you go broke. But M&A is the most likely success outcome, probably in 3-5 years' time.”

Waldie says things are going well for Opengear, especially with regard to technology innovation. The company is preparing to release an open-source SDTcon utility (ssh desktop tunnel configuration) that Waldie says will simplify configuration and management of ssh-based VPN tunnels. “SSH tunneling has been around for a while, but you have to be sophisticated to use it. SDTcon will let you do the same things you can do with putty, but with a simple pushbutton interface. You can push a button and establish a VNC client, tunnel to ssh, and connect to the remote host, for example.”

Waldie also reports that Opengear is doing well financially, despite its limited channel. “We haven't built a sales force. We rely on people coming to our door, but revenues are growing. It's all positive,” he said.


Both devices are shipping now, priced at $245 for the 2-port SD4002 or $595 for the 8-port SD4008.

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