BEAM Ltd
XVI - A TECHNICAL OVERVIEW
BEAM Ltd - September 1995
Introduction
This document gives an overview of the use of a BEAM XVI terminal in a typical networked system.The Network System
A common approach when using Unix based systems is to use a limited number of powerful servers together with Workstations all connected together using a Unix Network. Users access the Servers either via a personal Workstations or through an X-Terminal. The X-Terminal is a graphics user interface device allowing a user to run Unix X-Window applications from any of the Servers or Workstations.
With this system the applications run on either remote Unix Servers or local Unix Workstations. The applications present their graphics onto the display of the X-Windows Terminal via the network. This is different to the Microsoft Windows approach where applications run on individual personal computers on each desk. Both systems have merits and problems. Some companies prefer one approach to the other and some use both approaches on a common network.
The BEAM XVI Terminal
The BEAM XVI Terminal is like a conventional X-Windows Terminal with extensions to help the visually impaired user see and manipulate applications. The Beam XVI Terminal consists of a large colour monitor with keyboard and mouse and a box containing the display control system. It has the appearance of a conventional personal computer and is indeed based upon this technology. The system box is available in one of three forms:
The Mini-Tower system is the most commonly used as it allows the main box to be sited under the users desk leaving plenty of room on the desk for working. It also has expansion slots available for adding future XVI extensions such as a video camera document viewer.
The BEAM XVI Terminal is connected to the computing systems by means of an Ethernet network cable. Both 10Base2 and 10BaseT networks are supported.
BEAM XVI Extensions
The XVI extensions include the following features:
The BEAM user manual describes these features in more detail.
Implementation of BEAM Extensions
The BEAM XVI extensions have been implemented as an X-Windows extension with a Motif client providing a user interface and other functions. This method provides a high performance system with great flexibility for future enhancements.Installing a BEAM XVI Terminal
If the user is already using an X-Terminal changing to using a BEAM XVI Terminal is simplicity itself. Just unplug the old X-terminal from the network, plug in the BEAM XVI Terminal, setup the network address and all is ready to use. There are no changes necessary to the host systems. All of the XVI software extensions run on the BEAM XVI Terminal and thus have no effect on the network system. The local software extensions are also fast as the magnifier and other tools have direct access to the display hardware.If the user is using a Unix Workstation a BEAM X-Terminal can be situated alongside. The Monitor of the Workstation can be removed. The Workstation needs to be setup to present a user login, via xdm, on the BEAM XVI Terminal. This is normally a simple operation. Indeed on some systems it is already setup. The user can now login to the Workstation in a similar if not identical manner to before, but now has the XVI extensions to assist them.