You might think that from all the newspaper articles, technical papers, and public and government debate, someone somewhere had specified exactly what an Information Superhighway is. Not so; confusion reigns! There are as many notions of what the superhighway is as there are people talking about it, but nowhere is there a definition. So let us start by defining what the superhighway is not.

The Information Superhighway is not information transported over:

The Internet or World Wide Web
• The PSTN (Public Switched Telephone Network)
• The ISDN (Integrated Services Digital Network)
• ADSL (Adaptive Digital Subscriber Lines)
• ATM (Asynchronous Transmission Mode)
• Today's LAN & WAN circuits (Local & Wide Area Networks)
• CATV (Cable Television)
• Any network that is asymmetric (different bit rates in either direction)
• Any medium that causes a delay of more than 30ms
• Any medium that constrains the bit rate to less then 1Gbit/s

Why be so specific and selective? Well, ultimately, the Information Superhighway is about instant gratification, and access to information at anytime in the right form, and at the right price. Because we are able to absorb information at rates up to 1Gbit/s, and perceive delays of the order of 30ms, bandwidth and delay are critical success factors. Long delays are irritating and disruptive. This is evident on transatlantic telephone calls where the satellite path (~50,000km) can introduce delays over 300ms. Double talk due to echoes are very common, and conversations stilted and difficult. In contrast, a conversation over a submarine cable incurs only a 30ms delay, and is perceived as perfect. Similarly, at a computer keyboard, network delays of several seconds are common and limit our rate of work. If you are a user of the Internet, minutes can pass while contacts are established and information transferred. To say the least this is extremely irritating and limiting!

Internet - The Bizarre Bazaar
There is no doubt that the Internet is a path finder and precursor to the Information Superhighway. However, explosive growth combined with concatenated electronic bottlenecks, restricted bandwidth, and long, unspecified transmission delays make it behave like a crowded footpath rather than a highway. Moreover, the organisation and assembly of information make it something of a bizarre bazaar. It is all shiny and glitzy, and you feel that the information you want is in there somewhere, if only you could find it! What is actually required is the information shopping mall with organised information, where you can find what you are looking for, and where there are established pedigrees, prices and values.

The Realisation
How are we supposed to realise the shopping mall vision? There is only one technology that will give us the capability required by the Information Superhighway. It is optical fibre which is devoid of electronic bottlenecks. Network transparency is the only economic means of providing sufficient bandwidth over global distances. All of the necessary technologies exist, most are tried and tested, and a good percentage are being deployed. Optical fibre that amplifies and maintains its bandwidth over hundreds of thousands of miles is now an engineering reality.

Intelligent software agents and information systems able to seek out data, assemble it, and return it to the originator of the request in far less then a second are either under development or already exist. What does not exist is the underlying architecture, software, and infrastructure needed to realise this vision without significant delays. The computer industry, and to some extent the telecommunications industry, continue to hold onto protocols from the copper past. Protocols such as X25, X400, frame relay and many more were designed for an age that is now gone. Unfortunately, protocols that are equally silly, given our optical fibre abilities, are still being created. ATM is an interim, and perhaps necessary step, but it causes unpredictable and variable delays, between packets and sessions that most certainly constrain the bandwidth. Futhermore, each ATM switch also introduces a delay of about 7ms, plus another unknown, variable delay. The concatenation of only a small number of ATM switches could make some services unworkable.

The personal computer industry is doubling the power of its machines every one to two years. Common clock rates are now 25, 50 or 100 MHz, and at the top end, power PCs are using 160MHz, with the next generation aiming at over 300MHz. The amount of RAM is now commonly 8MBytes and rising to 32MBytes with disk storage commonly 500 or 1000MBytes. Given these trends, it is clear that current network technologies are likely to introduce significant bottlenecks. The inability of telecommunications networks to respond to the demands of their peripheral terminals will fundamentally constraint progress in the first part of the next millennium unless the right network technology options and designs are selected now. We must base the decisions on economics and technical ability rather than politics and corporate correctness. If we do not, we will pay the price later.

What We Need To Do
To realise the dream of the information society based on the superhighway, it is essential that we do not build a footpath or a cart track! It is absolutely fundamental that we start with a vision of continual growth and expansion for 30 years. To do this, requires a small number of key decisions, concerned with network infrastructure, to be made.

1. Single mode optical fibre everywhere.
   
2. Optical amplification instead of electronic regeneration.
   
3. The minimum of electronic switching and routing.
   
4. The eradication of all switching through the development of intelligent optics.
   
5. The adoption of network topologies that allow a rapid migration from where we are today to where we want to be in 10, 20 and 30 years time.
   

The Race
For nearly 100 years after its creation, the telecommunications network was ahead of the peripheral technologies, and well able to serve the needs of society. However, during the last 15 years, it has gradually slid behind developments such as the personal computer. For the users of such machines, it is exceedingly limiting to have massive computational power at their finger tips only to be constrained by a pair of copper wires and a 14.4kbit/s modem. At such data rates, cruising the Internet is a lifetime's occupation! Pulling down pictures, information, and movies is infuriatingly slow and archaic. Although the ISDN at 2 x 64kbit/s offers a dramatic and immediate improvement, and multiples of 64kbit/s - up to 2Mbit/s and beyond is even better, ultimately, the problem re-occurs. What is actually needed is that the telecommunications infrastructure - Information Superhighway - is able to stay ahead of developments in peripheral equipment. We must ensure that the network can always offer more transmission capacity than the users' computer ports demand. This becomes crucial when we consider that the super-computer on the desk, and in the home is only a decade away. Such machines will be throttled by copper, and radio in their role to act as our agent and work space. They, and the society they support, can only be properly serviced via optical fibres and transparent networks

The Experience Society
The idea of mankind's evolution from hunter gatherer, to farmer, to industrialist, and more recently to information worker, is now well established. It is now worth asking a most fundamental question: What happens next? It is reasonably easy to see where we are going - towards the experience society. Access to information is just the first step in the direction of access to direct experience. Television and telephony effectively extend our sight, speech and hearing over vast distances so that we can see and talk with other people. Research on tactile gloves, prosthetic arms, and tactile and prosthetic suits is already reasonably well advanced, and could extend sight, sound, touch, and position not only into the real world but into computer generated worlds. With such capability as the ultimate objective, the notion of asymmetric operation with lots of bandwidth to the customer and very little bandwidth from the customer either at home, in the office, or on the move is clearly a big mistake. Ultimately, we will need to communicate with vast amounts of bandwidth in both directions. The question is how much bandwidth? Humans are able to absorb information at about 1Gbyte/s, and with a modest amount of compression (8x) this can be reduced to 1Gbit/s so this, therefore, is a reasonably safe lower bound for the superhighway's data rate.

Delay
What about the effects of delay? If you stick a pin in your finger, the time between the point puncturing your skin and the ?ouch!? emanating from your mouth is around 30ms. This happens to be about the same as the time taken by a photon to travel from London to New York over an optical fibre - very convenient! This means that any prosthetic capability will incur a delay double that along our limbs, and slightly longer than that through our visual and auditory cortex. We specify hi-fi systems with a low-frequency cut off in the order of 30Hz; flicker is imperceptible on TV, films and video at frame refresh rates between 30 and 50Hz depending upon content. Curiously, the periodic time associated with these frequencies is approximately 30ms! 30ms is also the delay that defines our mutual, acoustic interaction over about 10m or so. For mankind this delay is thus on the limit of our natural abilities.

And Ultimately
There are neurological and evolutionary processes that fundamental define the capability of human beings. Some of these align well with the evolutionary capabilities of our technology. Should these capabilities concur in reality, we will have reached an optimum balance between man and machine. Ultimately, we can envisage the extension of our sensory systems along optical fibres to allow us to participate in new experiences that will change our perception of the world and the way we work and live. Virtual reality is one small step in this direction, with our sight and sound extended into computer generated worlds that are real or imaginary. Tactile and prosthetic extensions of our nervous system will help to complete the illusion of being there, and allow us to have new experiences and sensations, both real and artificially generated. To allow the experience of a top surgeon, scientist, teacher or artist, or allow presence at a sporting event, library, or museum to be shared by a large number of people, requires a broad bandwidth and minimal delay. Optical fibres are the only technology that can provide the necessary network transparency. The TV, radio, computer, telephone and systems of today are fundamentally limited - at best they can only provide a narrow window, and are incapable of delivering direct experience at all!

Future Prosperity
Experience in industry has shown that cost savings in excess of 35% in production engineering and time savings of more than 50% in the design cycle can be achieved by using advanced visualisation techniques. The ability to build a 3D model, on screen, is a significant advance over 2D paper drawings. When dynamics and animation are included, the process improves beyond all recognition. To be able to test out all the physical, systemic and integrated dynamics of a design, before production begins, offers vast savings. Limiting this process, today, is a lack of communication bandwidth. Dispersed organisations have to rely on the postal system to transport discs and tapes between R&D, design and manufacturing units across the globe. What should take seconds or minutes actually takes days or weeks!

The same is true for education, training, health care and all other activities. As the technology speeds up, rapid access to data, information, experience and solutions will be essential. What is relevant will change continually - keeping informed and up-to- date will not be possible with the old tools of teaching, learning, recording and decision making. Indeed, they will become largely irrelevant as they are fundamentally too limited and slow .

As we move towards the new millennium, it is the speed of communication, interaction and information access that will dictate the productivity of whole economies. Operating a modern economy without a super highway will be like running a country with cart tracks instead of motorways. It will still work - but only just!