X11 or X has historically been the protocol which allows terminals to be connected to a Linux server. X11 is a hardware intensive protocol and not ideal for today’s relatively low powered thin-clients.

1 - VNC Protocol

The VNC protocol enables a remote X display on the terminal. The image is constructed, maintained and updated within the Linux server’s frame buffer, and transmitted across the TCP/IP network.

The benefit is a VNC client requires fewer resources (memory and CPU) than an X based terminal. This offers a cost-effective and efficient X11-compliant terminal.

Often the VNC protocol is used to remotely administer Linux or Windows servers. To provide a 'multi-user' capability, Axel provides a Linux configurator at no charge. (AxGVNC)

AxGVNC analyses the Linux server’s settings and performs modifications to enable a 'multi-user' capability. With AxGVNC each VNC terminal has its own environment: a logon screen authentication (username/password) followed by a desktop (KDE, Gnome...) from where any application can be run.

Useful links:
   - The Linux VNC Server: RealVNC or TightVNC
   - AxGVNC : Click here

2 - RDP Protocol

The RDP protocol is well known by Windows administrators. This protocol is a standard feature of Windows Server versions and allows standard thin client connections.

There are several 'RDP server' products are now available for Linux. These allow thin clients to attach to a Linux server using RDP, providing logon authentication followed by a desktop (KDE, Gnome...).

Two RDP servers are available :
   - An Open Source project: Xrdp
   - A commercial product: ThinStuff LX Server