Standards to Support National Cooperation in Applying Technology to VET 

Videoconferencing

• 1. Flexibility and Options in Training Delivery
• 2. Importance to VET Sector
• 3. Current Technology Approaches in the VET Sector
• 4. Likely Industry and Society Developments
• 5. Appropriateness of Recommending Particular National Technology Standards
• 6. Options for Consideration for Adoption by the VET Sector
• 7. Value Assessment of Possible Options
• 8. Recommendations

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1. Flexibility and Options in Training Delivery

Most learning at present takes place with the client attending a classroom, laboratory, place of work or other location where a teacher instructs in or demonstrates a particular base of knowledge or skill.
Videoconferencing allows communication between the teacher and clients who are remote from the physical learning environment. The clients may be communicating from home via a PC or from a regional telecentre using either a PC or room installed videoconferencing equipment. Guest experts can be 'brought in' to supplement a class as well, using public or private videoconferencing facilities, adding a 'real world' exchange for students remote from those environments, anywhere in the world.

2. Importance to VET Sector

Videoconferencing is a potentially powerful technology for the VET Sector because it provides multimedia (voice, video, text and graphics) communication between the participants in the learning process. Videoconferencing is a good medium when interaction is expected and desired: it is not television in the broadcast sense of the word. High levels of production, in the TV broadcast/telecourse model, are not required; rather self-managed classroom teaching with adaptation of materials to suit the different format.

Teaching methodologies chosen should take advantage of videoconferencing when appropriate to do so. A good instructional design support program will help to identify areas that need adjusting to the new medium and ways that videoconferencing can bring new opportunities for better teaching and learning.

The ability to transmit moving video is particularly beneficial in cases where manual skills and techniques are being imparted. Videoconferencing technology has also the capability to transmit still and moving graphics (diagrams, sketches etc.) which can greatly facilitate learning in an interactive environment. The latest development of including data sharing also leverages investments in other computer based technologies such as presentation systems [Powerpoint], multimedia software teaching systems [Macromedia Director], and standard office productivity tools [word processing and spread sheets] in a live, interactive, and manipulable way.

These combinations of input/output devices can support a rich teaching and learning environment. The type of application for which the equipment will be used changes the decisions or range of options required for an installation. Quality concerns may be higher for administrative negotiations where facial expression is an important communication signal, but in a standard teaching activity, the image quality may be less demanding. The need for a personal space for individual connections may be suited with a desktop videoconferencing approach in a smaller office space. It would also be a waste of space to put a single person in a large lecture theatre. But a teaching application may range from a small tutorial room to a large lecture theatre at the originating program site.

Motivators and Incentives, Assumptions and Perceptions

Videoconferencing as a delivery mechanism for education and training can succeed or fail based on the understanding that the organisation has of its advantages and limitations in serving learning needs. Therefore the technology choices made should take these factors into account for specific situations within a VET organisation. Some relevant observations are:

• Completion rates are found to be very high in videoconferencing courses, in many cases much higher than online courses or other traditional distance education modes.
• Student incentive to participate in videoconferencing delivered classes is also important. One factor of value is reduction in travel distances to access programs, particularly those living in regional or remote areas. Local urban students find the medium less attractive.
• Room systems are good group environments for teaching applications, despite the hyperbole surrounding PC and IP based videoconferencing.
• The student profile that is attracted to videoconferencing as a learning medium may vary. Age and experience may be factors to adjust for in this medium, just as they often are for online computer based delivery. Other factors include the pace of the program, the access arrangements, differing program needs, and learning styles.

3. Current Technology Approaches in the VET Sector

The use of videoconferencing for flexible delivery and for administration varies widely across the national base. South Australia is a particularly large user and has an extensive network of sites. Most other states use videoconferencing on an occasional basis over a lesser number - typically half a dozen - sites.

The current status is summarised in the following table:

Table 1. Status of Videoconferencing in the VET sector.

The most commonly used equipment is PictureTel. States using this technology include South Australia, Western Australia and NSW. Victoria uses VTEL and PictureTel equipment.

4. Likely Industry and Society Developments

Worldwide, videoconferencing is on a relatively slow learning curve. The advantages of videoconferencing, at least in the business sector, in terms of convenience and travel substitution need to be qualified by more subtle behavioural needs in the social context concerned. In the education sector, the economic value of not travelling is not as significant as the combination of wider convenience factors such as domestic conviviality, given the sacrifices students make to their study.

Education is, however, a major user of videoconferencing.

The conduct of a successful videoconference has two aspects. One, the technical, is assisted by sophisticated production techniques including tracking cameras and directional microphones. The hardware and software to achieve this on an economic basis is still under development. The other, the human communication dimension, is assisted by well-developed practices of interaction, equivalent to but different from those used in face-to-face situations.

In the longer term, the inevitable decrease in the price of broadband communications links and improvements in video coding techniques will allow high quality videoconferencing to be conducted over statewide distances at reasonable costs. Simultaneously, the increased use of videoconferencing will lead to familiarity with effective ways of using the communication channel.

The industry will, clearly, evolve in two directions:

• Increased use of multimedia or telematic equipment will allow documents, spreadsheets and access to Web sites to be shared by participants in a structured way, including collaborative multimedia production and the evolution of Virtual Studios and Virtual Theatres and
• Increased use of videoconferencing to the desktop or PC will occur as prices for the powerful processors necessary - either the CPU or specialised hardware - fall in accordance with computing equipment trends.

In the longer term, the inevitable decrease in the price of broadband communications links and improvements in video coding techniques will allow high quality videoconferencing to be conducted over statewide distances at reasonable costs.

5. Appropriateness of Recommending Particular National Technology Standards

The improvements in coding technology and the falling costs cited above mean that the attractiveness of videoconferencing as an aid to flexible delivery is increasing. Consequently, penetration in the VET Sector is likely to increase in the next few years. Because incompatible standards in the industry already exist and significant costs can arise when it is necessary to convert between standards, it is now appropriate to minimise these potential hurdles to interoperation by identifying preferred standards for the VET sector.

6. Options for Consideration for Adoption by the VET Sector

Available standards comprise formal standards and non-published proprietary standards.

The formal standards for videoconferencing originate primarily from Study Group 15 (Transmissions Systems Equipment) and Study Group 8 (Terminals for Telematic Services) of the International Telecommunication Union-Telecommunication Standardisation Sector (ITU-T).

The H-series and G-series Recommendations (SG15) cover videoconferencing terminals, multipoint control units, and video and audio processing techniques. The T-series Recommendations (SG8) provide a standardised set of protocols that supports multimedia applications including fax, still image transfer, annotation and file transfer.

The overall standards for videoconferencing are defined in the following Recommendations:

• H.320 Narrow-Band Visual Telephone Systems and Terminal Equipment. (Defines how the H-series videoconferencing recommendations work together for ISDN).
• H.321 Adaption of H.320 Terminals to B-ISDN. (Defines how H.320 Terminals should operate with a broadband ISDN network).
• H.322 Visual Telephone Systems and Terminal Equipment for Local Area Networks that Provide a Guaranteed Quality Service. (Defines how H.320 Terminals should operate when connected to an isochronous LAN).
• H.323 Visual Telephone Systems and Terminal Equipment For Local Area Networks that Provide a Non-Guaranteed Quality of Service (Defines conferencing on conventional LANs).
• H.324 Terminal for Low Bit Rate Multimedia Communication. (Analogue telephone line videophone standard).

The umbrella standard, H.320, specifies further recommendations for the components of the overall videoconferencing system. The video coding algorithm comprises analog filtering, format conversion, temporal filtering and video compression in accordance with Recommendation H.261. A newer Recommendation, H.263, has been developed for use with high speed modems on analog phone lines. This Recommendation has superior performance to H.261 at low bit rates and will be employed in H.320 systems using ISDN and analog voice connections. Importantly, Recommendation H.324 allows for the use of H.263.

The audio compression algorithms prescribed by Recommendation H.320 are G.711, G.722 and G.728, depending on the audio bandwidth and the compressed bit rate. Recommendation G.722 is an improved audio coding technique, which uses adaptive differential pulse code modulation (ADPCM), but which is not specified by Recommendation H.320.

Within the system defined by Recommendation H.320, Recommendation T.120 covers the protocols for interworking telematic equipment. Recommendation H.221 covers multiplexing and demultiplexing of the video, audio, data and control signals into a single bit stream carried, if necessary, on two 64Kb/s channels.

Most US and virtually all European and Japanese manufacturers use the mandatory standards discussed above. Some manufacturers have, however, achieved wider functionality using proprietary standards. Videoconferencing via PCs and on the Internet is likely to be dominated by de facto standards and standards established by the Internet Engineering Task Force.

For off-campus students, approaches to the implementation of videoconferencing within the VET sector comprise

• The use of equipment compatible with standard H.320 and using 128Kb/s links comprising two ISDN B-channels.
• The use of H.320 equipment and 384Kb/s transmission
• The use of H.324.
• PC videoconferencing using proprietary standards.

Combinations with streaming video across the Internet [multicasting] are options for reaching new audiences in Internet connected spaces, such as the workplace, community centres and libraries. Other mixes of formats raise other technical and management issues as the capabilities may differ across platforms, and the additional requirement of a gateway for signal conversion may not be achievable or may increase cost.

7. Value Assessment of Possible Options

• In examining videoconferencing as an overall option for flexible delivery, there is an interaction of supply, demand, and perception of need that should be analysed. It is important to understand how important a particular program is and to ascertain whether there are other less expensive ways to deliver it. The key question is: Does videoconferencing make sense in this particular instance. In this regard, access and equity balance to cost may be valid justifications for a videoconferencing option, not just overall financial benefits.

The preferred standard is that which provides the best combination of value and interoperability.

Value is defined as the benefits to the players in the online delivery value chain minus the cost. The players in the delivery chain comprise

• Content providers,
• Teacher/trainers,
• Learners and
• Institutes or Industry Training Bodies.

Benefits and costs applicable to these players are given in the Report cited.

To determine the best combination of value and interoperability, the value diagram shown below is used. In this diagram, the benefits and costs are semi-quantitatively plotted against the inclined axes. The value, being the difference between them, is proportional to the vertical distance above the origin. It is scaled along the left hand side of the matrix. The horizontal axis of the matrix measures the interoperability of the standards considered. This will depend on:

• the openness of the standard and
• the degree to which the standard is already deployed in the VET sector.

Figure 1. Value and Interoperability for Videoconferencing Standards

Off-campus Learners

Clearly, it is difficult to quantitatively determine the benefits obtained from the use of the various videoconferencing standards. Nevertheless, the following procedure attempts to semi-quantitatively determine the value of the different standards options and plot them on the diagram.

Because of the avoidance of travel costs (including time and convenience), online applications like videoconferencing tend to be relatively more valuable when deployed over large distances. The model we consider assumes 4 sessions (each of 1/2 hour duration) per week over a distance of 1000km.

The effectiveness of videoconferencing depends on the support of the teachers involved. Difficulties in setting up videoconferences, malfunction of the equipment and poor perceived quality can reduce teacher commitment. The use of an assistant at the teacher's end is therefore assumed in determining the total cost. The videoconferencing and communications equipment (installation and rental) costs are annualised costs allocated on a per session basis. The transmission costs are based on Telstra's current prices of a two-site connection.

The relative costs of using the relevant standards are shown in the table below.

Table 2. Costs for Videoconferencing Standards

The analysis assumes that the central site is used much more intensively than the remote site and that the cost of terminal, communications and gateway equipment is therefore relatively small when allocated on a per session basis.

Videoconferencing is providing benefits in the VET sector by improving communication between administrative staff in Institutes and teachers and clients. H.320 at 128Kb/s is most commonly used. When the teacher is supportive, 128Kb/s quality is judged to provide adequate fidelity for clients. This is particularly so when the audio quality is high, as H320 provides. In fact, there is an opinion that higher video quality leads to expectations of broadcast quality production standards, which could not usually be cost-justified in the VET sector.

We assume therefore that H.320 (128Kb/s) has a positive but small value. The standard is therefore located approximately in the region shown on the diagram. The use of H.324 would, presumably, result in slightly lower quality, but with the advantage of slightly reduced cost. Its location can be estimated as shown in the diagram. It can be seen that these two standards appear to have roughly the same value.

The use of H.320 with 384Kb/s transmission would result in slightly better video quality, but at more than double the cost. It would seem doubtful that the resulting value is positive.

In terms of interoperability, H.320 (128Kb/s) would score highly because of the extent to which it is already deployed,. Other standards would require gateways to allow interoperability. In the case of H.324, this equipment is not yet commercially available.

CU-SeeMe desktop videoconferencing, an informal standard, could offer comparable benefits and costs, but would have much lower interoperability because of the smaller amount of equipment already deployed.

The technical quality of current videoconferencing on the Internet suffers due to low quality audio and less reliable video connections. Care should be taken when making assumptions about the appropriateness of incorporating an Internet option at this point in time.

Interworking between H.320 and proprietary standards is possible via a gateway. Significant operating charges are, however, incurred.

The various standards can therefore be located on the value diagram as shown above. It is seen that H.320, using a transmission rate of 128 Kb/s provides the best combination of value and interoperability.

There are considerable benefits, in learning via online delivery, of being able to transmit graphics, including material on whiteboards. The ability to share data and programs between the source and the desktop is also of benefit in certain learning situations. Standard T.120 provides this capability.

Their may however be additional costs involved in implementing the standard as not all vendors include the this standard in their normal product range. Interoperability will also, therefore, be correspondingly low.

On-campus Learners

In the case of videoconferencing conducted within campuses or institutions, transmission will usually occur over a LAN or WAN. In this case, the video quality (i.e., the predominant component of benefits in the value analysis above) will usually be adequate.

Value will therefore be maximised by minimising the cost of operations. This may involve the exploitation of available capacity on the LAN or WAN. Networking via a privately owned microwave network can provide low cost connections within a single institution.

In terms of interoperability, the emerging open standard H.323 forms the best basis for videoconferencing on campus. To maximise interoperability to other sites - including off-campus learners - the implementation of gateways to H.320 systems will be required.

The value and range of applications of the relevant standards may be summarised as follows:

Table 3. Videoconferencing Standards

8. Recommendations

Standards

The following are recommended:

• H.320 operating at 128Kb/s.
  References: http://www.imtc.org/standards.htm
  http://www.imtc.org/h320.htm
• H.323 on campus including gateways to H.320 systems. Reference:
  http://www.imtc.org/h323.htm
• T.120. Reference:
  http://www.imtc.org/t120.htm

Operating Guidelines

In addition to the general technical communication protocols required for videoconference interoperability, there are other technical and non-technical elements that facilitate best practice use of videoconferencing in an education and training environment.

Workshop participants agreed that the design of a videoconferencing delivery system should be driven by the needs of users, rather than technologists. Pedagogical issues must take priority over IT issues: the educational integrity must be maintained first. The technical aspects must support solid teaching and learning rather than insisting that the teaching and learning submit to the expediency of the technology decisions.

The implementation of videoconferencing is most successful when it occurs in a trusting environment where experimentation is valued and participants learn from mistakes.

Although each implementation may need to make decisions based on its overall situation and capabilities, the areas identified in this section should be considered in the design of videoconferencing systems.

Technical
The choice of technology needs to match the application. Desktop or PC based videoconferencing is a personal space while room systems are generally for groups.

The user interface device also needs to match the situation. A keyboard device that requires extensive text can only really be efficiently managed by a single person. A keypad device with minimal switching actions could be managed by a leader in a larger group. This person should also be charged with mic muting if the individual participants do not have individual press-to-talk microphones.

Peripherals
Recommended peripherals are:

• Scan converter for computer based information such as presentation graphics
• Document/graphics camera for showing real objects and writing
• Videotape recorder
• Monitors : 1 - 4
• External speakers preferred
• Phillips fluorescent tube for colour balance: TLD 83, SS
• Teacher preview monitor
• Echo cancellor
• Desktop units should be equipped with earpiece rather than open speakers to avoid echo problems

General Environment

• Help desk access should be available through a speed dial telephone in the room for assistance in case of technical failure.
• Booking facilities should not be located in the videoconferencing room
• For heavy use facilities, the furniture should be arranged for good viewing angles to the monitors and avoidance of reflections from lights
• Room lighting levels should be 50% above office lighting levels. This can be achieved by the use of 3 tube fixtures with plastic diffusers at the normal light fitting spacing
• Electrical and communications cables and wires should be installed in conduits to avoid safety hazards in pathways within the room
• In multipoint conferences, microphones should be muted unless speaking
• Carpet should be installed for better acoustic
• Avoid castors on chairs to discourage unnecessary movement

Staffing
A thin, but coordinated videoconferencing management structure is required within the Registered Training Organisation. It should comprise

• Manager - member of executive
• Program coordinator (education) partial
• Site coordinator (booking)
• Task force of coordination across institute

Position descriptions need to be modified to address these new demands and skill expectations for both teaching and support staff.

General Issues
The VET sector should participate in bulk buy contracts and industry initiatives in approaching the carriers to reduce ISDN prices.

Issues to be Reviewed

The following issues should be reviewed. July 1999 is an appropriate date.

• H323 - IP and LAN developments, is it yet viable for a production option?
• H324 - viability for analog access to homes on narrower bandwidth devices
• T.120 for datasharing and whiteboarding
• Internet and hybrid delivery of videoconferencing
  • Web based quality of service
  • Virtual private circuits
• WAN trends in owned networks and use of excess capacity for videoconferencing applications
• Techno-economic aspects of metropolitan videoconferencing
• Polling systems - multiple choice keypad devices
• Video streaming: one-way, - return chat text

[The 1999 Report]

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Last modified on May 05, 1999.