The right solution for Education

Topcat is a new software product from Microlynx and Acorn Computers that has been designed to enable Acorn computers and Windows PCs to be seamlessly integrated. A Topcat solution is the ideal platform for implementing an Information and Communications Technology (ICT) solution in an education or business environment. Topcat is required to enable the new Acorn Sprinter computer to be used either as a fully compatible low-cost RISC OS machine or as a powerful Windows Based Terminal.

Topcat also allows many existing Acorn machines to be used for Internet access and use the latest Windows applications. It enables Acorn computers to take advantage of hot new technology from Citrix and Microsoft that enables a thin-client/server solution to be implemented. Thin-client/server technology is currently revolutionising the computer industry and many large organisations have already implemented systems. We believe this is by far the best way to implement computer systems where large numbers of different devices are required and resources to implement and manage the systems are finite.

Topcat maximises the useful life of existing computers and provides a pathway to future technologies such as smaller and faster client devices and bigger and more powerful servers. It allows an organisation to take advantage of world-wide industry standards whilst maintaining individual control and flexibility.

Implementing a successful networked computer system is a specialised task and therefore Topcat is now available through highly skilled Acorn Network Centres who have many years experience providing solutions designed for use in education and business.

Since the early days of computing, as technology allowed a migration away from centrally controlled mainframe machines to empowering the end-user with desktop computers giving them unparalleled flexibility and choice. However, this did not come without considerable cost. Aside from the cost of multiple copies of applications, managing a large number of separate desktop computers, each requiring system configuration, version control, support and data replication quickly became cost-prohibitive.

As use of a mixture of different types of computers start to be introduced into an establishment, this in itself brings its own set of problems. What is needed is a system allowing different types of computers – for example, Acorn, Personal Computers (PCs) and other types of computers to be used and seamlessly integrated. Also, it makes no sense to discard older computers if they can be cost-effectively made to do the jobs which are needed.

The trend is back towards centrally controlled and administered systems – similar to the mainframe days - but with the important distinction that the end-user is still able to run the applications he/she needs and has the flexibility and performance required, but without the maintenance headaches which separate desktop devices impose. The use of Server-based and thin-client/server computing will help to reduce the cost of running, maintaining and delivering quality computing power to where the end-user needs it.

Before investing in any new computer system it is important to assess the needs of the users, how the systems are to be managed and used, and the performance required. Most importantly, the effort and costs of owning the systems needs to be estimated at the outset. Usually the initial hardware accounts for only a very small percentage of the total life cost.

Schools, colleges and other education establishments have special needs. The end-user – a primary school pupil to an under-graduate at university all have differing needs, and all usually share a smaller number of computer systems. So the systems have to be flexible enough to adapt to changes – from session to session and as the curriculum changes for a wide range of different users.

In probably no other industry does the technology get superseded as quickly as the computer industry. It is therefore important to try to ensure that the new systems have as long an effective life as possible. The use of server-based systems and thin-client/server computing will allow establishments to keep up with advances to technology cost-effectively and within the budget of cash-strapped organisations. By upgrading just the server it is often possible to take advantage of the latest technology and deliver the improved performance and enhanced range of applications to existing client devices.

A plethora of different computing platforms, operating systems and applications can and does cause immense headaches for the hard-pressed ICT administrator, technicians and teachers. So it makes sense to extend the life of existing systems wherever possible – all those man-years of training will therefore not be wasted. Where new systems are introduced, it is important to get good quality training in their administration, configuration and use in order to get the best out of them.

Of course, selection of application software will depend on the job in hand. However, with the system described, the flexibility is there to use RISC OS or Windows applications as appropriate.

Server-based and Thin-client/server solutions such as Topcat allow all configuration to be realised at the server(s). Such centrally-managed systems simplify the task of adding new client devices and configuring them to run new applications. For example, when adding a new Acorn Sprinter client to a Topcat system all that is needed is to connect the client to the LAN, note its interface identity and add this ID to the server’s DHCP database.

Care has to be taken to get this element of the system correctly designed, otherwise problems will arise which are difficult to resolve or isolate. For small installations a Local Area Network (LAN) consisting of hub connecting the client devices to the server on a single sub-net may be adequate. However, as the system grows the need to distribute the clients over a widening geographical area and to allow network performance issues to be addressed will necessitate the introduction of additional sub-nets, with either switches, routers or both. However, the use of Thin-client/server computing imposes very little load onto the network – only screen updates, key and mouse clicks are passed over the network, so an already heavily loaded network may even be relieved if existing networked devices such as PCs are converted to thin-clients. And the bonus will be reduced management overhead!

It is essential that whatever system is chosen that it is appropriate. Clearly an over-designed system may give good performance but will cost more than an appropriately designed system. This means that the requirements need to be carefully specified, analysed and a solution designed which fits these needs in a cost-effective manner, yet delivering the performance and facilities required.

Application installations, updates and additions are made only once – on the server – and then are instantly available to users anywhere, with exceptional performance. ICT staff have the ability to manager applications on the network from a single point and provide system-wide security for data and applications.

With thin-client/server computing, the security of applications and data is dramatically improved since all vital information is kept on a centralised server. Actual data never gets downloaded to an end-user device, so critical applications and sensitive student information remain safe. For example, if using the Acorn Sprinter, which has no local hard disc or floppy drive, ensures that pupils cannot introduce viruses from floppy discs onto the system.

With a Topcat solution, Schools, colleges and other academic institutions are better able to extend the use of existing hardware and networks. Existing Acorn computers can be converted to Windows-based terminals or be used to surf the World Wide Web. Heavily loaded networks may be given a new lease of life by adopting thin-client/server solutions.

Most schools and colleges have many different types of computers, operating systems, LAN protocols and network connections. Providing pupils and students the choice to run RISC OS or Windows applications would in traditional environments mean separate hardware. With a Topcat solution this can be achieved with a single type of client device without compromising performance. Also the same server can provide services for many different types of computer giving unparalleled flexibility.

By using common server(s) for all types of computer the management overhead is minimised. Server-based and thin-client/server computing make managing many different applications and computers easier. Control and security is easier to manage, as everything is centralised.

10Mhz Ethernet using unshielded twisted pair (10BaseT) is a reliable and flexible type of networking for schools. This is easy to install and easy to re-configure or extend. This superseded the older version using coaxial cabling (10Base2), which is susceptible to variable performance and its operation is dependent on all connections and terminations being correctly made.

For heavily used sections of networks, the use of ‘Fast Ethernet’ operating at 100Mhz may be recommended in certain situations. However with thin-client/server solutions, the demands on network bandwidth are quite modest such that replacing 10Mhz sections with 100Mhz sections may be avoided.

Thin-client/server solutions lend themselves very easily to extending the reach of networks to satellite annexes without the need for high speed WAN connections. The demands on network bandwidth for thin-client/server computing allow low speed connections to be used – dial-up analogue over PSTN, ISDN or leased-line depending on usage patterns, distance and costs.

Also access to the Internet for web browsing, e-mail etc can be delivered quite easily from the server using a proxy server allowing security and caching of frequently access pages.

TCP/IP is a widely-used routable protocol that is the basis for communication on the Internet. NetBEUI is a fast protocol used originally with older Microsoft clients, but because it is non-routable it is only suitable for LANs. So you may need to use both. The Acorn ICA client supports only TCP/IP as a transport.

If the client devices need no individual configuration – e.g. if one goes faulty, just replace it and the new one works in exactly the same way as the old one without the need for lengthy re-configuration, this will greatly reduce the amount of effort needed to keep a large network running. Centralising the configuration onto the server makes life much easier for hard-pressed system administrators, technicians and staff.

This is an important issue. Windows NT has a rich set of features and facilities for ensuring that only authorised people have access to the system, can open only those files and directories which the administrator has granted permission. Also with important data centrally stored, keeping them safe from prying eyes is inherently easier. For thin-client/server the important data files never leave the server. Keeping data centrally also allows easier backup helping ensure that your data is safe from hardware failures.

Windows NT allows you to track a number of different account-related events and record user activity for later review.

Tools to monitor and troubleshoot the performance of the server and network are built in to Windows NT. In addition, the Citrix Metaframe system allows a user’s session to be shadowed allowing remote instruction – for example the teacher is able to control the user’s mouse pointer to show a student how to do certain tasks.

The use of Windows NT is the natural choice for server in a mixed Acorn and PC system. By using Topcat, the Acorn computers can boot off the Windows NT Server in native mode – there is no need for third-party NFS server software. Also, existing disc-based Acorn computers – such as the A3020 can run the latest version of RISC OS (3.71) and version 4 if/when it is released without the need for a ROM upgrade. In addition, the opportunity to use the Acorn kit to access Windows applications or the Internet is easily achieved.

Windows NT can provide user authentication for many different systems, including Acorn computers, PCs etc. For the Acorn platform, it is only necessary to have a single user identity and password to access the server in RISC OS and Windows modes. There is no need to have separate user names and passwords with the inherent difficulty of keeping these in step.

Users can switch easily between the different modes – for example pressing Shift-F1 from Windows will return the user to the RISC OS desktop. To resume the windows session, the user just double-clicks on the ICA icon on the icon bar. As user accounts are common between the two modes, files are automatically accessible in both modes. Also users can share files with others on the network – PC or Acorn users.

Education environments pose special challenges for networks and computer systems. Used as a common resource, computers need to be able to present personalised profiles no matter which workstation is used. Roaming profiles on the Windows NT allow a user to log on and get the same desktop and facilities no matter which workstation they use.

When budgets are tight, it makes sense to try and get the best value for money. Part of that goal will be to extend the useful life of existing hardware. Also typically ICT administration in education does not get the numbers of people resources which would be expected in typical business situations. So the management of the system needs to be extremely easy and efficient.

Schools provide particular challenges for networks – for example as all the pupils in a class start on a particular session, the demands to boot and load applications on 20 or 30 machines simultaneously pose interesting problems for the design and throughput of the system. So, instead of pseudo-random loading, there is a tendency for much more peak activity at certain times.

It is important that all elements of the system are reliable. So if fault-tolerance can be built in to the system, this will help keep things running. Good network design coupled with the fault-tolerant facilities of Windows NT will help ensure that the system has high availability. For if something can fail, you can be sure that it will!

By using a thin-client/server solution such as Topcat, it is possible to keep up with the latest developments and access the latest applications relatively cost-effectively. By upgrading the server as the need arises, users can take advantage of improved processing power and have access to the latest applications.

We took delivery in September 1998 of 30 Acorn NCs together with a Fujitsu server running Microsoft NT Server 4.0 (Terminal Server Edition) and 'TOPCAT' software which enables the whole system to boot into RISC OS. The NCs were a straight replacement for a room of ageing A3000s and 3020s, and when booted up into RISC OS the new NCs run all our existing RISC OS software (with very few exceptions e.g. Teletext software, though in fact we believe that this might now be possible), enabling compatibility with our existing Acorn machines.

All our existing teaching programmes are proceeding on the NCs in the same way as they were on the A3000s. One of the new Applications is the Citrix client software to enable the machines to run a Windows NT session (this looks very similar to Windows95), so that all 30 machines can be running Windows applications, such as Word97 or Access97. These applications run fast, as they run on the powerful server, rather than on the client NC, and installing new applications requires only a single installation on the server, rather than 30 installations on 30 machines. Many of our 6th form groups, and individuals, choose to run the NCs like this in Windows mode rather than in RISC OS, but both are available and both equally effective.