Abstract

The paper describes a way of managing computer lab environments that will ensure consistency of operation with less hardware asset, and administration effort. Using Open Source technology Lab Admins can give greater access to users to do creative things with computers, knowing that the underlying network retains a default consistency for the next user to use the workstation.

Background

My network engineering classes are often permutated with the three words every network engineer must weigh up when deploying services to users. In fact whenever I ask a question to these IT professionals to be, they will often answer around one or more of these points.

Stability – Is what you are deploying going to suit the intended purpose, and consistently operate for every user

Security – Can we rely on mechanisms to ensure that users don’t impinge on other users, either maliciously or unintentionally

Integrity – Are we sure that the systems operate as intended and do not introduce inconsistencies into the work environment Business Classes however look at technology differently

Cost/Benefit – When is payback for the outlay for technology, either in productivity, efficiency or increased growth.

Competitive Advantage – Can we do unique things with the technology that will put us ahead of our competitors.

I would like to have a look at these issues in relation to a radically different deployment of PC environment using Open Source technology.

Technology

1. Use Open Source

What is Open Source: Software where the source code is available for anyone to extend or modify. http://www.opensource.org/. That is the development and betterment of software that is in public ownership.

Much as been produced under the banner of Open Source and compendiums are often produced. Called distributions, they either sold with support contracts or freely distributed by commercial or non-profit organisations.

Linux – Probably the most talked about Open Source release and the least understood. Linux is the core operating system for many distributions and simply provides the interface layer between a wide diversity of computing hardware and applications that users interface with. Linux is used in everything from electronic door locks to super-computing environments.

From a business perspective; this technology is free to use, modify and redistribute. The one caveat is that redistribution cannot then be re-sold with a commercially restrictive license.

Proposed Deployment

2. Bootstrap the PC over the network

The network is more important than the software by which access is gained. We have seen that information technology has encompassed networks to provide a service-oriented view of information, and the clients we use for access have become standards-based. That is, the ways in which we access information have standardised and the information itself becomes dynamic to the users that access it.

Devalue the desktop and redirect effort toward maintaining network infrastructure. Technology in the late nineties started to integrate extensions that allowed booting from the network (http://www.pxe.ca/). So instead of a hard drive, floppy or CD, users could get boot images over the network to allow the machine to start. The architecture of Microsoft Windows has yet to enable LAN booting, but Linux will boot over the network as quickly as if it were installed locally on a hard drive.

Viewing the desktop computer as a hardware entity, instead of the inclusion of software and operating system, allows technical experts to focus on the desktop environment that applies to all users. Updates are then propagated consistently to all users after each modification and then reboot.

Disadvantages

Windows is the dominant flavour for computing, Linux can be made to look similar, but will behave differently. IBM’s implementation strategy is to use Open Source technologies that emulate the Microsoft Office suite (http://www-1.ibm.com/linux/solutions/ximianlinuxsolution.shtml). Others may provide a windows desktop via a Terminal session (http://microsoft.com/rdp). The Open Source rdesktop project (http://www.rdesktop.org) can be in netboot start-up script to give instant access Windows servers.

Increased points of failure: Technically a netboot environment needs two computers for success. The netboot fileserver and a netboot client. The chain of communication between these two entities have points of failure. But the role of network is becoming so integral, that access to the modern Windows environment would be impossible without a network server (http://www.microsoft.com/ad).

 
3. Manage desktop changes from a File Server

Reliance on competent Net Admins to ensure continuous improvement takes place without paralysing the entire LAN environment. Proper change management procedures are required to ensure avoidance of a desktop disaster.

Advantages

Stability: Computer clients will never be in an inconsistent state (or they will all be in an inconsistent state). Users cannot change desktop settings and take individual desktops out of the default environment.

Reduce the number of components in a PC, you reduce the possibility of failure. The PC with no moving parts has an extended operational lifespan (http://www.silentpcreview.com/article141-page1.html)

Security: Much effort in ensuring safety of desktop hard drive contents are made irrelevant. In fact it allows users to have broader controls over their computing appliance, because changes last for as long as power is supplied to the computer. A reboot equals a total refresh to the default desktop environment.

Access control must then apply to the network and network services that the desktop has access to. Strong firewall rules permit a restricted set of protocols out over larger networks. Net Boot environments can be made to authenticate with most standards-based directory services and/or even two-part authentication (http://rsasecurity.agora.com/rsasecured/guides/imp_pdfs/CheckPoint_VPN1_4.1_SecurID.pdf)

Traditional PCs remember a previous user’s sessions, sometimes in secure environments. Web caching represents a user’s access history. Rebooting a diskless workstation clears all cache data, and browsing history. Making this perfect for access in public environments.

The slogan in the mainframe days was “protect your interests logoff”. The netboot environment could be similar, but instead of logoff, users can press the reset button.

Integrity: The consistency by which deployment of applications across all LAN desktops increase users’ understanding of what a PC is capable of, irrelevant of its location on the environment.
 
4. Share the technology with everyone

Being devoid of a restricted redistribution license, any organisation can modify and duplicate the environment for users to access the tools in other locations, like home, or on a laptop.

Cost/Benefit: Savings can be made in:

Hardware – No expensive fixed or removable secondary storage is required.

Desktop Support – User training and support remains, but technical support of desktop systems for everything but hardware is negated

GNU (http://www.gnu.org/licenses/gpl.html) – Is the legal license of Open Source. There are rarely any licensing costs for applications in a Linux distribution and commercial/government organisations can deploy any number of desktops with the software at no cost.

Competitive Advantage: Open Source advocates shared innovation. i.e. the whole community should benefit from software extension efforts. This has not been an impediment for the likes of IBM and Sun in implementing Open Source. The growth of Open Source technology will be a major benefit, but the customisation opportunity gives business and education alike the chance to configure an environment to suit their own specific computing needs

Conclusion

Net Boot PCs are best used in public access environments (no password access), and Educational environments where students need to innovate with technologies without restrictive user desktop control policies.

The educational community has a responsibility to advocate Open Source as it emulates the openness of learning with a shared community vision for technological improvement.

Try the technology today, download Knoppix 2.4 (http://mirror.aarnet.edu.au/pub/knoppix), burn the ISO on a CDROM - Click Knoppix menu -> Network Services -> Knoppix Terminal Server. Then netboot your client PC!

John Perry
LMS Coordinator The Bremer Institute of TAFE