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The Virtual University - a Cable Perspective

Stephen Giles and Chris Avram,

Computer Technology Department

Monash University



The emergence of new communications networks and conferencing technologies provides scope for extending the boundaries of the traditional University. This paper describes an investigation into a practical implementation of a system incorporating some aspects of these emerging technologies in a higher education environment. Initial outcomes, as well as possible future areas of investigation, are discussed.


An important issue for Monash University (as well as all other educational institutions) is to find new ways of providing student access to lectures and to lecturers. The traditional on-campus lecture to a number of students requires the students to be in attendance on that campus and seated in a lecture theatre. In order to increase the efficiency of teaching, and access to subject areas on many campus sites, the University has implemented Teleteaching systems between most campuses. Lectures are now presented at one or more locations using videoconferencing systems via ISDN-based communications links to provide the remote presence for the lecturer. Video-on-demand trials are under way for student access to video materials at the PC desktop. Additionally, many subjects make use of web-based resources for teaching-support or as a replacement for face-to-face teaching.

The Growth of the Web and new Conferencing Technologies

The general computing community, as well as the educational community, has seen the rapid adoption of the World Wide Web over the past few years. In the Higher Education area there have been the many web-based developments targeted at what has been termed the Virtual University. Many subjects have part, or all, of their support materials provided via WWW pages. These web-based initiatives may be providing just another way of presenting the material, i.e. an electronic form of the printed matter; or they may be presenting the learning material in a form that moves far beyond just a representation of the content, e.g. simulation, etc.

A limitation of many of these WWW systems is that access is to relatively static resources that, although providing teaching material in an easily accessed form, have limited real-time interaction capabilities.

The recent development of conferencing technologies - audio, video and application/data - has now provided an important adjunct to these systems. Applications supported by these new technologies would provide the support necessary for this remote education to succeed.

By using a combination of these web and conferencing technologies, the common view of a future virtual university, consisting of a small campus site housing the administrative services necessary to support the teaching and the teaching staff, could be a reality. Students would work from home, attending lectures via the Internet. They would be able to meet with their lecturers for informal discussion, and more formal tutorials, via the same medium.

The Cable Project

In early May 1997, the Computer Technology Department began trials of a project where two lecturers were in contact with their students and other staff members via a home-based cable modem service. The cable modem service used for the trial is similar to the types of service planned for implementation by many communications service providers around the world. Due to its availability, the cable modem supplied by Telstra was chosen for the trial.

At the beginning of semester two in July, students from the two lecturer's subjects were invited to participate in trials where they could contact staff for consultation using NetMeeting (or any H.323 and T.120 compliant application). They were be able to conference with the lecturer's office and home machines from either their home Windows95- or WindowsNT-based machines, or from the Windows95-based laboratory machines of the University.

The staff members used the systems as if their home offices were an extension of the normal workplace, carrying out their everyday management and academic tasks.

At the end of a suitable time-period (end of the summer semester 1997/98), assessment of the suitability of both the conferencing products as well as the cable modem service will be conducted via the staff and students being surveyed as to their perception of the effectiveness of systems similar to the trial systems. There will also be some analysis of the cable modem system's technical capabilities and costs to investigate its suitability for supporting the application of conferencing to an educational usage.

Telstra Multimedia Web Site

Student and Staff Access to the University Network

Many staff members and students are currently accessing their University-based resources from home. Most access the University network and the Internet via the dial-in services provided by the University. A growing number are choosing to access the University networks and the Internet via Internet Service Providers (ISP). In the future Virtual University it is likely that most staff and students will be accessing the University from sites that are off the campus and many will be using the services of an ISP.

Technology to support student teacher consultation

The primary needs considered in this technology review are for interactive consultations between students and teachers. Clearly, such consultations are best conducted in person, thus maximizing the communications channel bandwidth. If some particular presentation device can improve face to face communications, then surely such a device used by the two communicants in the same location is the best way to maximize communications.

So why interpose technology into the communication? The most common reason is cost. The cost of time spent travelling, the cost of travel itself and the cost of teachers themselves. Another common reason is the lack of time for travel.

The second best solution is to use communications technology to enable the nearest thing to a face to face consultation. Such a communication should be immediate (not store and forward, not a system such as email), should be human contact rich (not text based, not a system such as IRC, MUD), should facilitate joint consideration of collaboratively produced materials (not just a telephone or video conference but one that allows computer screens to be shared). Let us call this teleconsulting.

The Options for Access from Australian homes

The typical student home computer is an Intel Pentium based personal computer operating under the Microsoft Windows 95 operating system. There is a variety of PC Internet based software facilitating live interaction with a teacher or course adviser. In this section, we describe the options for connecting such a PC to the Internet and in turn to a computer at a teacher's home or office. These options are 1) plain old telephone service (POTS), 2) Integrated Services Digital Network (ISDN), 3) Cellular telephone service (cellphone) and 4) Cable TV modem (cable).

Each of these services will be described in terms of cost, availability, data transfer rate, other features and futures. Many of these attributes will vary from time to time and place to place. The data presented will be based on late 1997 Australian conditions.

Plain old telephone service

A. Cost

It may seem trite, but worth saying anyway, the telephone is the lowest cost, most widely available device for student consultation at a distance. There are a number of devices that add video to voice in telephone calls, the extremely low levels of use of such devices is an indication that the added cost of video alone to a telephone link has not been worth the approximately $1,000 additional capital cost over the basic $100 cost of a telephone. In addition to a telephone, a remote student will need a telephone service (installation $250, annual rental $150, usage cost from $0.25 per local call up to $30 per hour for interstate calls).

The current range of PC based video conferencing software [1] may change this. Why? Well given a PC and network connection, the addition of video to a live audio link, costs about $250 for a camera [2]. The audio though much reduced in quality from what it might have been, had video not been added, the audio is still equal to that available over a telephone line. So for a small (additional) cost video is possible.

Of course the cost of a PC, video or no, is about $1,500 over that of a telephone alone. The Monash Computer Technology trials make use of computer software that facilitates collaborative computer operation, voice and video communication - what we have called teleconsulting [1]. Given that a student must have a computer for their studies, a telephone to survive in the Australian society (installation $250, annual rental $150), the additional cost of facilitating audio, video and shared software teleconferenceing is the cost of a camera ($250), modem ($250) and an Internet Service Provider ($20 per month). The operating costs are about $3 per hour independent of distance.

B. Availability

The availability of POTS in Australia is excellent. The waiting time for a new service is only a few weeks. Only the most remote of students (less than 1% of the population) will have availability problems. The availability of Internet Service Providers (ISP) in Australia is also excellent. Many remote locations have a local provider if not, there is an Australia wide service operated by Telstra with local call fee access.

C. Data transfer rate

All communications in a teleconsultation are transmitted in digital form. The total (best) data transfer rate possible over a POTS service is a full duplex 56,000 bit/s. This figure is only meaningful in comparison to those of the other services considered below. Many country students and even students in built up areas under some adverse conditions will be restricted to data transfer rates of 28,800 bit/s. This is adequate for voice, video and slow software collaboration.

D. Other features and futures

One major problem with POTS teleconsulting is that often the only telephone in the students' house is engaged during a teleconsultation so the student can not ring out for telephone support to help resolve problems with the operation of the teleconsultation. Let us call this the engaged phone problem.

There are teleconsulting software packages designed for direct person to person POTS calls, these packages allow conferees to switch between telephone operation and teleconsultation. Such facilities though not available in Internet based teleconsultation yet, may be added as a purely software feature to existing systems so overcoming the engaged phone problem.

Integrated services digital network

A. Cost

ISDN services in Australia are sold by Telstra [3]. Installation is $350 annual rental is $720, usage charges are $2.50 per hour plus about $10 per hour for access to an ISP. ISDN can be used for ordinary telephone calls so replaces the POTS service. One can even operate a POTS modem over an ISDN service. There is additional hardware required for ISDN operation. A terminal adaptor, typically called an ISDN modem, costs about $650. All ISDN calls are charged for time and distance. Typically, phone calls are less than 3 minutes duration and if your average domestic call is less than 3 minutes, then ISDN may reduce your telephone call costs by about 4%.

B. Availability

ISDN is very widely available from Telstra under the product name Onramp. Telstra claims that by December 1998, 96% of Australians will have ISDN services available to them [4].

C. Data transfer rate

The domestic ISDN service can transfer data at either 64,000 bit/s or 128,000 bit/s depending on the system configuration. ISDN is full duplex. The higher rate is charged at twice the lower rate per hour.

D. Other features and futures

ISDN does not suffer from the engaged phone problem. Even if a student has decided to only have an ISDN service, there are still two separate channels available. If both are in use during a teleconsultation session, and the phone is picked up, the ISDN modem will automatically and transparently close down one ISDN line and make a telephone service available. This data call is automatically resumed after the telephone call.

A terminal adaptor allows two concurrent analogue phone, fax, modem connections over the one ISDN service. Customers typically have two phone numbers, one for each of the analogue lines.

Cellular telephone service

Data transfer rate

The cellular telephone system can be used for Internet access. The data rate of the GSM network is limited to 9,600 bit/sec. This is inadequate for teleconsulting.

Other features and futures

The cellular network is good for mobile operation but not yet adequate for full collaboration or videoconferencing.

Cable Modem

A. Cost

The cable modem network is a data only network. Prices given here are based on the Telstra service over the Foxtel cable TV system [5].

The cost of hardware (Motorola Cybersurfer modem) for Internet access over the cable is not a simple matter; we paid $650 plus a connection fee of $30. This is subject to a surcharge of $780 if we don't keep up our monthly subscription of $60 per month. The licence is for one PC and one copy of the software needed to connect the PC to the cable. Usage charges are very difficult to estimate. The monthly charge includes up to 100Megabytes of data. Each additional Megabyte costs $0.35 [6].

A typical 10-minute teleconsultation call using Microsoft NetMeeting will involve 500,000 bytes of data and cost $0.15. Relatively cheap compared to some other activity. For example a 3 minute video clip of a pop song is 7 M bytes and costs over $2.00 and a 1 hour interactive combat game such as Team Fortress involves the transfer of 10 M bytes and costs $3.50. One of the test sites allowed non-accounted and uncontrolled use of the cable for a two-month test period. This family of four was surprised at their usage. The monthly data transfer notional charge was over $500 for over 1.5 Gigabytes of data.

B. Availability


The availability is only in selected suburbs of selected cities, we estimate that less than 50% of the Australian population have access to cable as at October 1997.

C. Data transfer rate

The data transfer rate over cable is excellent. It is asymmetric, the data transfer rate from the Internet to the attached PC is up to 10,000,000 bit/s. The data transfer rate from the PC to the Internet is 768,000 bit/s. In practice, given various bottlenecks this translates to a typical down load rate from a typical site in the USA of 90,000 byte/s for a 20 M byte file. The data rate is much more than adequate for teleconsultation.

D. Other features and futures

Since the data is transferred over the cable TV system, the household telephone is still available during data calls so avoiding the engaged phone problem. The cable modem provided by Telstra allows four PCs to concurrently use the Internet at one location over a local area network.

There is in our opinion a significant problem with Internet cable modem use. The cost is potentially too great. One test household consists of two computer active teenagers. When the system was first installed, Telstra did not charge for data transfer, so the household was allowed unlimited access. Within one month, the data transfer rate reached 1.5 Gigabytes per month at a potential usage charge of $500 per month. In fact, given the peak transfer rate of 10 M bit/s, once the first 100 M bytes are used up, charges can accrue at up to $0.35 per second or $1,200 per hour. How? Well four PCs can be attached and all four can be down loading data at once. For example each 3 minute popular music video clip costs $2.45. Live TV (Real-Video) costs $9.00 per hour per channel per viewer.

In the future, the cable service may become more widely available so suitable for distance education, however there are significant infrastructure costs to achieve that. There are also significant cost control problems for customers.

Outcomes to date

The students

The initial student population of approximately 300 students was encouraged to use this facility. Resources were made available (e.g. an Internet Locator Server was run on a Windows NT server for NetMeeting use, a local FTP site was setup for the necessary software) and all technical information needed was also accessible. Of this group a number (approximately 50) tested the system. A smaller number (around 20) used NetMeeting for one-to-one audio sessions over University dial-up facilities. Most chose not to participate. This may have been due to this being seen as a non-mainstream function for the students and therefore of less importance. It may have also been too involved for the students given other pressures for their time. It is expected that during the next phase of the process the students will be interviewed to ascertain the reasons for their lack of involvement. Activity was logged of a more casual nature via the Internet Locator Server, which indicates that there was some less-formal use of this medium that was not reported by the students.

The staff

The staff members found a number of positive outcomes. Firstly, the performance of the home workstation was now at least equal to the work environment, if not better in some sessions. The convenience of carrying out all normal day-to-day tasks at either the home or office was seen as a significant improvement to their work-life. After the initial technical difficulties (of which there where few), an almost seam-less home and workplace environment was available.

Future investigations

The current investigation has tended to focus on the communications technologies and to a lesser extent upon the conferencing technologies. As the networks both within, and external to, the University improve in speed and quality of service, the focus should turn to the conferencing products, as it will be here that advances such as multipoint conferencing make the most impact.


Of the many techniques for bringing remote students into closer contact with their educational institutions, the newly emerging cable networks are likely to become important features of the communications landscape. However, the limitations of availability and cost will be obvious barriers to the expansion of the University beyond its physical boundaries.


[1] ... (1997) Microsoft NetMeeting Microsoft Inc. accessed October 21, 1997.

[2] ... (1997) Color QuickCam Cybout Inc. accessed October 21, 1997.

[3] ... (1997) OnRamp - Telstra's New ISDN Services Telstra Corporation accessed October 21, 1997.

[4] ... (1997) ISDN Frequently Asked Questions Telstra Corporation accessed October 21, 1997.

[5] ... (1997) Telstra Big Pond Cable Internet Telstra Corporation accessed October 21, 1997.

[6] ... (1997) Rate Card Telstra Corporation accessed October 21, 1997.

[7]Ö(1997) Motorola Corporation accessed October 21, 1997.

[8] Microsoft NetMeetingTM 2.0 Resource Kit, Microsoft Corporation, 1996.


(c) Stephen Giles and Chris Avram


The author(s) assign to ASCILITE and educational and non-profit institutions a non-exclusive licence to use this document for personal use and in courses of instruction provided that the article is used in full and this copyright statement is reproduced. The author(s) also grant a non-exclusive licence to ASCILITE to publish this document in full on the World Wide Web and on CD-ROM and in printed form with the ASCILITE 97 conference papers, and for the documents to be published on mirrors on the World Wide Web. Any other usage is prohibited without the express permission of the authors.


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