Executive Overview

American Hytech integrates computer and multimedia technology for delivery in government and corporate facilities. The Hytech system leverages multimedia equipment by bringing all the technology together in one central location. The idea is to centralize media in an institution, improve information access, and bring information into the company with technology that's easy to use.

Today's Multimedia Network

The main types of building/campus A/V (voice, video and data) network configurations are listed below, along with advantages and disadvantages of each. This is a review of the modern advances in audio/video and data technologies, and the impact these new technologies have on the signal delivery capabilities built into each type of system.

Note: Telephone and data requirements, and their wiring configurations, are considered to be the same in both systems described below. Comments and comparisons generally relate to the technical aspects of delivering the audio and video media programming to the appropriate destinations.

Integrated Information System Network

This system consists of separate control A/V (audio/video) delivery, and LAN and telephone cables (installed together in a common "star" backbone configuration). It utilizes a central routing switch and supervisory computer to distribute and manage A/V programming and data to and from the destinations. Cabling for the computer LAN and telephone services parallels the Video cables. The "head-end" provides the foundation for all of the integrated Voice-Video-Data services.

This system architecture provides the highest bandwidth capabilities to the destinations. The single head-end concept provides a "natural" foundation for additional future integration of the various VVD services and it will easily accommodate future signal quality and format upgrades. Video of compressed origin (MPEG etc.), once recovered at the head-end, can be transported to destinations at full resolution (it does not need to be recompressed). A switched wideband design easily transports analog and digital signals (compressed or uncompressed). High quality "discrete" stereo audio as well as CD digital stereo is very cost effective to encode or decode, and therefore common on these systems.

Future Network Designs

Delivery of compressed high resolution MPEG-2 HDTV signals over broadband cable will be possible in the next several years. The FCC has defined the basic specifications and feasibility has been proven. Final specifications are expected to be approved in 1996. However, because of the complexity of real time encoding these highly compressed high resolution signals, it will be very expensive to locally encode the source signals. The HDTV MPEG-2 design provides inexpensive decoding electronics (mass consumer oriented). But, it requires very expensive encoding hardware at the broadcast point of origin. This means that since any high resolution video transported by a broadband multichannel cable must be compressed, any local video sources or live origination will not be high resolution. The concern (with broadband cable) at this point would be that there is a quality difference between broadcast programming and instructional media programming.

It is predicted that someday all voice, video, and data required anywhere, will be available from one optical fiber (most likely using ATM). However, in reality, the type of network this service would require is not widely available yet. It will be cost prohibitive for several years to come. The technology to network the tremendous bandwidths required for a true, multi-user, high quality, full motion, high resolution video, VVD-LAN is also several years away. The coherent light optical technology and optical routing equipment which will be required has yet to be perfected.

Video Conferencing
The "Face-to-Face" Conference

Our vendor partner's Video Conference Services are powerful tools for helping your business work smarter. They bring people, ideas, and information together efficiently ... using either group video systems or personal computers equipped with video capabilities.

Having one of the world's largest digital fiber networks, our vendor partner's range allows you to reach numerous locations and maintain a high-quality connection. That means whether your meeting involves two nearby locations or dozens of locations on several continents, our vendor partner's Video Conference Services are the perfect source for reliable video communications.

These Video Conference Services offer advanced bridging features ... and free testing of connectivity between your equipment and our bridge. Choose the options that fit your needs best:

• Connect three or more sites with multipoint bridging
• Connect locations with dissimilar video equipment with Codec conversion
• Connect locations using different digital transmission speeds with speed conversion and rate adaptation
• Connect network-linked locations linked to other Spacenet locations with GE Spacenet Satellite Services
• Enhance video quality with inverse multiplexing to combine channels for increased bandwidth

There are two Video Conference Services initiation options:

• Dial-Out – You set the reservation, our vendor partner will dial out all participants and bring them into the meeting.
• Dial-In – Meeting participants dial into the video conference for greater flexibility.

Hold a face-to-face meeting with video conferencing and:

• Choose the Best Billing Option ... host or end user, single or multi-location.
• Call detail gives you flexibility in managing and controlling billing to meet your business needs.
• Don't Miss a Thing ... see multiple locations on your video monitor at the same time.
• Keep in Control ... make changes to your conference call using a separate touch-tone phone.
• Add Audio Participants ... include audio participants who are "on the road" or don't have access to video equipment.
• Be prepared ... in the unlikely event that video capabilities fail, you have the option of switching to audio-only mode.
• Get Off to a Great Start ... a professional greeter will introduce each entering participant as they join the call.
• For the Record ... have your conference recorded for people who can't attend in person.
• Coming or Going? ... exit/entry tones let you know when a participant is entering or exiting your conference.

FVC

A t the other end of the spectrum lies outbound learning, which does not require a physical campus at all. One of the first to provide education through TV broadcasts in the 1970's, Open University in the United Kingdom is now pioneering distance learning via the World Wide Web. Courses are taught entirely online with no face-to-face teaching. The purpose is to create a new generation of 'digital generalists,' people who feel equally confident about teaching virtual students in cyberspace as they are teaching real people in real classrooms.

Of course, most educational environments fit the campus model today, but there are clear benefits to the outreach potential of the cyberspace model, especially as the bandwidth and multimedia capabilities of the Internet continue to grow.

The writing is on the wall for education and educators. The survivors will be those who rapidly embrace a broad spectrum of technologies so they can offer the right mix of courseware in the most appropriate form to the widest possible audience-in other words, those that exploit the full potential of communications technologies to enable distance learning. Distance learning is a business imperative - turn it to your own advantage or ignore it at your peril.

Multimedia Comes of Age

Today's student population grew up around television and computer games. Their shorter attention spans crave action, sounds, pictures. Multimedia is more than a game, it's the only way to maintain their interest and full concentration. And as any teacher knows, students who don't pay attention, don't learn.

Multimedia is more than a game, it's the only way to maintain their interest and full concentration.

Now that fast PCs and high bandwidth networks are ubiquitous, the multimedia aspect of distance learning has really come of age. Educators can take their choice of anything from high-quality interactive, two-way and multi-way videoconferencing, multicasting of live video streams, recording, and video on demand playback, over private networks, public service networks, or the World Wide Web. Video is becoming an integral part of the distance learning paradigm.

The technology required for distance learning can be daunting. Let's start with the basics. To connect a teacher to a student, you need a network. Networks suitable for distance learning come in many shapes and sizes, from satellite transmission systems to statewide fiber networks. A variety of issues are involved in choosing the right network and equipment for distance learning.

Fundamental Video Types

Video is the primary medium of content delivery in distance learning. It comes in three types, video on demand, broadcast video, and videoconferencing, each of which is uniquely suited to different learning scenarios.

Video On Demand

This is one-way, streamed video. It enables a distance learner to access educational content that is stored on a video server. The content may be a recording of a regularly scheduled lecture that a student could not physically attend or a program that was recorded in a studio for the purpose of later viewing over the network as part of standard coursework. Because video on demand is the simplest form of video networking, it is starting to appear over the Internet, even though the video and audio is very low quality today. The nature of one-way, non-interactive video allows for some buffering of video at the edge of the network, smoothing underlying latency and inconsistency of the transmitting network, so it's possible to provide video on demand over virtually any network. The range of quality levels available obviously depends on the type of network the video is traversing. With the right network, anything from Internet quality to full-screen, HDTV quality is within reach.

Broadcast Video

This is also one-way, streamed video, except that it is one-to-many - just like TV. In distance learning, it enables a teacher to simultaneously reach any number of learners located across the network. The broadcast may come from a camera that is capturing a lecture in progress, or from a live feed from cable or satellite into a broadcast server. Or, it could be stored content that is broadcast over the network at a specific time. Broadcast video can also be recorded to a video server for later use. Live or stored broadcast video is harder to deploy than video on demand, because the network must support multicasting-otherwise, the video broadcast will consume great amounts of bandwidth and slow down all the PCs on it, including those not interested in watching the broadcast.

Videoconferencing

This is real-time, two-way interactive video. It is the only way to truly reproduce the classroom environment. Video cameras must be employed at all points of the videoconference to allow this two-way interaction to occur, and the network must support real-time data transfer in both directions. Videoconferencing enables virtual meetings and preserves the dynamics of inter-personal communication that occurs in real meetings, even though participants may be miles or countries apart. This makes it by far the most effective distance learning tool, for collaboration, group discussions, or Q&A with teachers or students. Not surprisingly, it's the most difficult type of video networking to achieve, because it places high bandwidth, performance, and efficiency demands on the network.

Understanding the Key Requirements

Video Quality

A critical success factor in distance learning. Regardless of the type of video that is being transmitted — live broadcast, video on demand or videoconferencing — the quality of the video is a key determinant in passing on the teacher's knowledge, because students quickly become bored or frustrated if the quality of the audio or video is substandard. A core challenge is how to provide the required video quality over a network with a wide range of transmission characteristics and capabilities. Today's Internet works great for data, but it was never designed to transmit high quality video and audio, especially not two-way. Only now are service providers turning their attention to two-way, interactive video over the Internet.

Video Compression

To transmit the typical analog NTSC or PAL video—the kind seen on television—it must be compressed. Various transmission protocols and compression standards have emerged to enable video traffic to be transported effectively over networks. For high-end videoconferencing, the standards that apply are ATM (H.321, H.310), IP (H.323), and ISDN (H.320). For video streaming, MPEG-2, MPEG-1, H.261, and H.263 are commonly used. All these standards have their places, depending on the type of video and quality level desired.

Equipment Mobility

To begin with, many schools can't justify installing video equipment in every classroom. This has fueled a growing trend to roll-about solutions, which can be moved from room to room, providing maximum mobility and flexibility. Because it is more cost-effective to move the end point, not the networking equipment, H.310, H.321, and H.323 have the advantage, because they don't have to be wired into every room like H.320 does.

End-to-end Dialing

For videoconferencing, it is critical to be able to make calls between any point on the network without administrative support. It must also be easy to use, with desktop control--perhaps through a familiar Web interface. When people can initiate calls on the fly, without needing assistance from a videoconferencing expert, they are more comfortable about videoconferencing and use it more often, leveraging the equipment investment without tying up valuable IS personnel. Today, H.320 (ISDN), H.310, H.321 (ATM), and H.323 (IP) allow end-to-end dialing with varying degrees of simplicity. However, non-standard implementations of H.320 videoconferencing over ATM prevent unassisted end-to-end dialing, and resources may be burned quickly as usage grows.

Multi-point Conferencing

An essential feature for distance learning, multi-point conferencing connects several classrooms simultaneously at different speeds, with a choice of how to view the participants. For example, everyone may be on the screen at once, just the presenter, or perhaps the last three speakers. This facilitates the use of experts from universities and learning establishments all over the world. For effective multi-point conferencing, it is desirable to reach different devices both within and off the network, linking room systems, desktops, even laptops in dorm rooms, using everything from H.320 and H.321 to H.323. The key is to be able to treat each caller at the best speed that each type of equipment can accommodate. Multi-point calls are so popular that many service providers now offer them as a standard service, making them as simple to complete as a multi-point phone call. For more control, institutions can add in-house, multi-point conferencing capabilities to their private networks using a multi-point conference bridge that supports transcoding and continuous presence, as well as gateways to interconnect between the various videoconferencing standards.

Conference Overflow

Multi-point conferencing ties up a lot of resources. Because many people don't need to be active participants in a call, conference overflow is a complementary solution that allows an existing videoconference to be seen by additional students.

Broadcasting Servers that broadcast live streams from cable and TV, as well as live events such as lectures, on campus and over the Internet, are key pieces of the total solution. Two important considerations are flexibility and video quality. If the network has sufficient bandwidth, go for the best quality video it can support. As far as flexibility is concerned, when most videoconferencing equipment is located in classrooms or lecture halls, the ideal scenario is to use the same equipment for both conferencing and receiving streamed video. Choosing equipment that supports both is an excellent way to reduce costs and maximize flexibility.

Recording and Storage

Any broadcast event or videoconference call should be recordable so it can be re-used. That means recording must be simple to set up from anywhere in the network by authorized users. It must also be easy for them to archive and annotate it, so the video is easy to find, and can be rebroadcast or viewed on demand by people who were not present at the time of the live lecture, perhaps because they were in different time zones.

Video on Demand

When students can access stored video lectures and course content from any PC on the network, they are free to learn at their own pace and can repeat difficult topics as often as necessary. Many educational establishments already have thousands of hours of courseware on videotape libraries. Each video is lent out like a book – to one student at a time. Archiving this content onto a digital storage server unleashes its potential, giving many more students unrestricted access to all the content at any time.

Scheduling and Management

Ease of use is as important as state-of-the-art quality. Scheduling and management of single and multi-point videoconferences should be easy enough for people to use without going through administrators. When everything is accessible through a Web browser interface, it is more accessible, easy to use, and network integrity and security are assured.

Billing and Security

While it is desirable to facilitate access and empower the students, there must be controls. Stored content is a valuable resource, and so is all the network and end point equipment required to support distance learning. Someone has to pay for it all, and schools may want to charge students for usage, especially when calls are made to distant universities or institutions. Whether a school uses a shared network, pays for access from a service provider, or offers courseware to other schools in the district, it is necessary to track usage so all the participants can pay a fair share, which may be a flat fee or a per-stream or per-call billing agreement.