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Console servers gain RDP, VNC tunneling

Nov 15, 2005 — by LinuxDevices Staff — from the LinuxDevices Archive — 2 views

A company making inexpensive console servers based on uClinux, Open KVM, and other open source software has added a unique SSH tunneling feature. Opengear says its CM4000-series devices are the first console servers offering secure, remote graphical desktop sessions using tunneled VNC or… RDP. The devices target enterprises, VARs, and systems integrators needing to securely maintain servers, software, or desktops at remote offices.

According to Opengear, VNC (virtual network computing) and RDP (Microsoft's remote desktop protocol) are secure enough for use on a LAN, but not on open networks such as the Internet. Hence, companies requiring remote access to graphical desktop environments typically have used KVM-over-IP (keyboard-video-mouse) devices from vendors such as Avocent or Raritan, or else have installed complex network-wide VPN (virtual private network) systems.

Opengear says its CM4000-series console servers can replace legacy KVM devices, while eliminating the need to install network-wide VPNs. Administrators can use the devices to securely access computers running any OS that supports console access or VNC/RDP, including Windows, Linux, Solaris, Mac OS, or Unix. Users, meanwhile, can gain access to all their applications, “as if they were sitting in front of their computer in their home-office,” the company says.

According to Opengear, the CM4000 devices implement SSH tunneling by forwarding selected TCP ports through authenticated and encrypted tunnels. Remote users can tunnel their VNC or RDP sessions to the CM4000 using broadband, dial-up, or ISDN. The CM4000 then forwards these sessions over the TCP/IP LAN to the remote computer being accessed.

Alternatively, the CM4000 can route remote users to the COM port of computers that are intentionally not connected to the local LAN. Such target computers could include medical equipment, or factory and plant automation equipment, Opengear says. Thus, according to Opengear, the CM4000 devices can be used by administrators to remotely manage computers, change Windows EMS or system BIOS settings, upgrade servers' operating systems, and reboot remote machines.

Opengear was founded in January of 2005 by Snapgear founder Bob Waldie, with the aim of leveraging open source software to reduce the cost of console servers. The company launched its CM4000 line on Valentine's Day.

Opengear followed up in May with the CMx86, an inexpensive PCI card that, along with a live CD open source distribution based on uClinux and OKVM (open KVM), can convert old PCs into 4-port KVM servers.

Tony Merenda, senior VP of engineering, said, “Our hardware-secured RDP and VNC are a much better alternative for small branch offices than more complex network-based VPNs. We have [fortified] these services with SSH tunneling through a secure hardware device while enabling further management, diagnosis, and recovery features.”

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