Elusiva terminal services for Windows XP: Saves energy, money and time (Part 1 of 2)
By Jeremy Pollard
Energy management, non-renewable resources, peak oil, energy costs and just about "green" anything are popular buzzwords right now. Computers aren’t immune to this environmental revolution – they consume piles of joules that cost money to use, and money to generate.
You know "thin" is in – and "fat" is officially out – when Google gets on board. And that’s just what the IT giant did when it re-designed its server farms to save energy – and ended up trimming $50 million annually from its budget.
Terminal services (TS) were once the platform and domain of all IT departments. You had to run TS in a server environment because it was a managed environment. Thus the IT group was involved because it was a server. And we all know what happens when servers, IT, and control guys get in the same room – that’s when the fights start!
This is not the case with Elusiva TS software. It runs on XP. Yep, that’s right, a normal desktop. We can have the same benefits as a true server environment under our own management, and save energy, money and time.
A TS client could be anything, really. An old computer could run Remote Desktop protocol (RDP) to attach to the TS server, but that would be defeating some of the purpose of going thin.
A thin client, typically, is a device that is based in firmware. It usually lacks spinning hard drives and features a small footprint, runs on Windows CE, and requires much less energy. I use thin clients from Esprit Technology, and their thin clients use 1.2 amps at 12 VDC max. A Dell server I have here uses over three amps at 120 VAC and a workstation is just under three amps. I’ll let you do the math.
There are two very distinct components for changing your approach to industrial computing – hardware and software.
The hardware is easy. Get a computer running XP and a thin client running RDP, and you have the requirements to run a TS environment. The RDP software is free from Microsoft, and there is a demo on the Elusiva website that you can run for two weeks to try this out.
The installation of the Elusiva server software is fairly painless. You have to have Internet access to register the licence even though it is free. It will not work otherwise.
Also, be aware that if you upgrade to a full licence you will have to re-install the software, and re-register.
You need to use GPEDIT.MSC to configure the TS environment on the Windows XP server. This is the real configuration exercise where you have to ‘allow’ a TS client to connect. Once that is done, any client can connect and compute in a TS session. You have to name the server, and then the system is ready to rock. The TS server is automatically active after a reboot.
The RDP software can access the server by the name given or the IP address. The user that you log in as must be a registered Windows user on the TS server along with a password. It is exactly the same as creating a new user locally through the control panel.
When you log in using RDP, you enter the user name and password, and the screen looks like a normal Windows screen. Be aware that the person who is running the Windows session locally is still active.
There are still issues surrounding running applications in a TS environment, which will be covered in the second installment of this column (available in the June issue), where we will deal with the Enterprise product from Elusiva. Suffice it to say that, in any application, you can use a thin client and a TS environment.
The applications that will benefit the most are SCADA. Depending on the platform, you can save energy, development and runtime costs, and of course hardware costs.
So for 50 bucks a user, you can have a distributed system, with secure and almost "maintenance-free" clients on the plant floor.
There is no performance penalty when using a TS environment and there is no limit to the number of users. Depending on the server hardware, applications, and connectivity, however, a load balancing system may be required. But that’s for next month.
Jeremy Pollard is a 25-year veteran of the industrial automation industry. He has worked as a systems integrator, consultant and educator in the field. You can reach him at firstname.lastname@example.org.