for the Next Generation’s Public Network?

The Awakening 3.0: PCs, TSBs, or DTMF-TV–Which Telecomputer Architecture Is Right
for the Next Generation’s Public Network?



Universal, equitable, and affordable access to the national information infrastructure (NII) is achievable over the next 5 to 7 years. However, our switched and broadcast telecommunications industries have not been given the national goal and task of pursuing the network architecture and technologies that can provide such access to interactive media public utility services.

At present, these communications industries are pursuing variations of the personal computer and TV set-top box network architecture models. These public network architectures are inappropriate and have economic handicaps that will cause them to fail in the provision of universal access and service for the American public. However, there is at least one network architecture model—DTMF-TV—that does appear capable of delivering on the NII promise. This “architecture,” based on the existing and universally available telephone and NTSC video networks, can provide universal and affordable access to the Internet, the Library of Congress, and any other source of entertainment and knowledge 1

. However, the NII needs an encouraging, supporting, and regulating public policy. This public policy should provide for the nationwide common carriage of real-time addressable video to the home, equal access to cable TV head ends for interactive multimedia providers, and the appropriate video dialtone rules.


The national information infrastructure (NII) is totally dependent on the proper convergence of our public switched telecommunications network (PSTN) and mass media public broadcast network (PBN) into a nationwide telecomputer system. Two predominant network architecture models and one emerging model are competing to be “the” information superhighway. The interactive media network architecture deployed by our nation’s cable and telephone companies will have a significant impact on whether the general public will begin to have equal, affordable, and universal access to the NII by 2000. Over the next 5 to 7 years we can expect the interactive multimedia industry to continue to improve PC technology and program content. However, the model that posits a PC in every home, connected to an online network of “PC” telecomputer systems, will fail to provide universal access to the NII because of the economic burden of PC hardware and software purchase and maintenance, and their constant obsolescence. Similarly, today’s cable and telco interactive TV trials, using the TV set-top box telecomputer system model, will also fail to provide universal access because of the same economic burdens of their underlying telecomputer network architecture. Unless the PSTN and PBN industries change their current architectural focus, we will continue down paths that will lead to greater division between our nation’s information haves and have-nots.

To best serve the public with interactive media services will require a fully integrated system of switched and broadcasted telecommunications common carriers. Considering the asymmetrical nature of interactive multimedia networks, the switching technology and broadband distribution media are already in place to integrate these information superhighways in a way that is economical for universal access 2

. Unfortunately, these key NII elements are owned primarily by two competing corporate entities within any given geographic locality. Even the aborted Bell Atlantic-TIC megamerger reveals the economic shortcomings of integrating the broadband loops of cable TV with the switches and back-office operations of telcos when they are not located within the same geographic locality. As a result, these telco and cable companies are struggling to add to their networks what the other already has in operation. For two capital-intensive industries, this economically taxing competition begs the public policy question: If building the information superhighway is so expensive, why, as a nation, are we trying to build two of them? The problem is that public policy has not charged our PSTN and PBN industries with the goal and task of creating a new and shared “public utility” system nationwide, a public telecomputer network (PTN) providing universal and equal access to interactive media on a common carrier basis. This is the strange attractor toward which our communications and computing industries have been converging since the breakup of the Bell system. However, the current chaos will continue and public network engineers will pursue inappropriate network architectures until our country proclaims such a goal with the proper laws to encourage, support, and regulate the enterprise.


Before 1993, the public policy issues surrounding the evolving NII were mostly limited to industrial infighting. It was the telcos versus newspapers over interpretation of the MFJ, broadcasters versus studios over Fin/Syn rules, and everyone taking opposing positions on the FCC’s proposed video dialtone rules. These public policy debates were, for the most part, kept within the communications industry establishment and the hallways and offices of Congress and the FCC. Then someone said “500 TV channels,” and visions of the entertainment possibilities and public service opportunities moved from the industry trade rags to the front pages and covers of our national consumer publications. This media attention captured the public’s imagination as the now infamous information superhighway.

Since then, most of our leading telecommunications and media executives have declared themselves “infobahn” road warriors. They rushed off to announce their respective interactive multimedia trials and megamergers to deliver tele-this, cyber-that, and your own personal virtual-reality Xanadu. Within the next 5 to 7 years, the public will expect the NII, as the next generation’s “public network” of switched and broadcasted communications, to deliver on these entertainment, education, and public utility promises. This is a major undertaking for private industry and public policymakers. To understand the network and regulatory engineering paradigm shift that must take place, one needs to comprehend the existing and evolving public network infrastructure within a common context. That context is “video dialtone.”

The current state of play within the industry involves two predominant, and one emerging, telecomputer system models. A telecomputer system, in the fuzzy macro context of the NII, is the mass media system that our nation’s cable and telephone companies are striving to create to deliver interactive digital everything to the consuming public. It is the underlying hardware infrastructure that will integrate telecommunications, television, computing, and publishing into a seamless national multimedia network.

The older and more familiar of the predominant telecomputer models is that of the PC in every home connected to the Internet and other packet-switched networks of computers. This is the “PC” model. Although this model was a dismal failure as a mass medium during the brief videotext era, it has had a recent resurgence encouraged by flashy multimedia PCs, GUIs, CD-ROMs, and the explosive worldwide growth of the Internet. The champions of this model tend to be the manufacturers and sophisticated users of advanced PCs, workstations, and high-speed data networking gear. The essential NII elements that this model brings to a telecomputer architecture are those that offer the most artistic, creative, and communication freedoms to users, programmers, and publishers.

The other predominant model, getting off to a dubious start, is that of the “smart” TV set-top box (TSB) in every home interfacing with a video server. This is the “TSB” telecomputing model. This model is the result of recent advances in microprocessor, video compression, and network transmission technologies. The champions of this model tend to be the manufacturers of cable converters, microprocessors, and midrange computers in partnership with cable and television companies. In apparent conflict with the PC model, the essential NII elements of the TSB network architecture are those necessary for responsible mass media broadcasting and network operator control. More important for the NII, the TSB telecomputer model recognizes the public utility potential of an unlimited number of addressable video channels to the consumer.

These two models expose most of the essential NII elements perceived by the converging industries as necessary for the successful introduction of a new mass medium. Between the two, it is possible to extract the inherent objective of a telecomputer system. The objective is to offer all consumers the potential and opportunity for interactive access to all multimedia publications over a public network. The objective is also to provide this access in a responsible and socially acceptable manner. Although each of the incumbent models has technical and philosophical advantages over the other, neither will pass the test of being economically feasible as a mass medium.

Taking lessons from early industry trial experiences and failures, just now emerging is a third telecomputer model. This telecomputer model envisions the public using ordinary telephones and Touch-Tone (DTMF) signaling over PSTN networks, and using only the buttons of an ordinary telephone as an interactive TV (ITV) “remote unit” to access and interact with centralized computers broadcasting user-personalized output over ordinary NTSC video channels. This telecomputer network architecture combines the best of the other two models in a way that can offer universal access to interactive multimedia services. The DTMF-TV model can deliver on the promise of common carrier interactive TV and programmer competition. Whether or not this public utility service will be made available to the public over the next 5 to 7 years will depend on the creation of a new video dialtone policy, a policy that will lead to fully integrated switched and broadcasted services on an equal access and common carrier basis. Such an NII policy should influence the choice of an appropriate telecomputer network architecture by our nation’s cable and telephone engineers.



To use video dialtone as a common context for NII issues, we need to define it. There are three distinct types of video dialtone networks and regulatory models. The first compares to traditional PSTN services because that is all it is. This video dialtone is now finding its way into the marketplace as compressed video teleconferencing and transfers of digital data to office desktops via multimedia workstations and data networking services. As the economics for these switched services improve, this form of video dialtone will likely find its way into the homes of telecommuters. Over the next 5 to 7 years, videophones and PC videoconferencing windows will penetrate the home in the same way that facsimile machines and other home office productivity tools do. This form of video dialtone, VD-1, is only a common carrier’s analog or digital switched service offered on demand. Switched point-to-point and bridged two-way point-to-multipoint communications, video or not, are covered by generally accepted PSTN regulations and tariffs.

The second form of video dialtone originates from satellite and local TV transmitters over federally regulated and licensed public spectrum. It also comes from cable TV head ends transmitting over locally franchised rights-of-way. This form of “passive” video dialtone is one means of access to the consuming audiences of the PBN. The public’s TVs are now limited to receiving their principal choices for necessary, convenient, and entertaining or interesting passive video program transmissions in this form. This nonswitched one-way, point-to-multipoint video delivery is the most efficient and economical method to distribute high-quality video programming to the viewing public on a “scheduled” basis. Advances in digital video compression and fiber optic transmission technologies have led to the potential for a quantum leap in the number of broadcast video channels that can be delivered to the public. These developments led to the so-called 500 channels and video-on-demand bandwagons. However, this form of video dialtone, VD-2, does not yet have a recognized and accepted common carrier regulatory model. When approached from the common carrier perspective there are some natural, yet severe, technical and network architecture limitations. These limitations relate to channel and time slot availability and social responsibility concerns. If the NII is to include a common carrier infrastructure that would permit any programmer or content creator equal access to America’s TV audiences, the evolving public network will require a virtually unlimited number of addressed video channels.

The third form of video dialtone is an integrated media mix of the PSTN and PBN, a “mix” permitting services with favorable economics for a national interactive multimedia medium. It is this evolving new form of public network dialtone (VD-1 + VD-2) that is of particular interest to the NII. This form of video dialtone is VD-3. It will be those “interactive and on-demand multimedia communications” services available from nationwide PTN networks on a common carrier basis. This form of video dialtone will satisfy the promises hyped to the public, thus far, as the information superhighway 3



A major factor affecting the evolution of the NII and the technology to be deployed for it is the need for a clearer understanding of just who are the “public” in the evolving public network. As the now separated wireline network industries converge on the fully integrated network services “attractor,” the characteristics that once distinguished video broadcast (VD-2) from switched telephony (VD-1) subscribers are rapidly blurring. This phenomenon will dramatically influence the VD-3 or “interactive video dialtone” regulatory model. Do cable subscribers want to subsidize cable’s entry into telephony any more than telco subscribers want to subsidize telco’s entry into cable? From an NII public policy standpoint, these subscribers are one and the same. They should not be burdened with paying for a redundant infrastructure in the name of full-service networks’ competition in a “natural monopoly” environment. To further compound this issue, as the wireless industries of over-the-air, satellite, and microwave broadcasters also converge on the same “fully integrated network services” attractor over the next 5 to 7 years, the issue of “who are the public” as public utility subscribers accessing this evolving public network will become even more blurred.

Over the next 3 to 5 years we can expect that the quest for spectrum efficiency on the cabled wireline side, through digital compression and multiplexing, will apply equally to the wireless over-the-air side of VD-2 video broadcasting. As the broadcasters of subscription channels (e.g., HBO, Showtime, Cinemax) continue to explore multicasting opportunities (e.g., HBO-1/2/3, ESPN and ESPN2), one can expect the more traditional VHF and UHF networks of the PBN (i.e., CBS, ABC, NBC, Fox) to want access to the same commercial opportunities. This trend, however, will require the NII to set VD-2 standards for compressed audio and video broadcasting in order to encourage a market for the associated consumer electronics (i.e., wireline and wireless broadcast receivers) and other addressable customer premises equipment (CPE). These standards may be based on a version of the Motion Pictures Encoding Group (MPEG) standard, the Asymmetrical Digital Subscriber Line (ADSL) standard, or some future NTSC/FCC or industry digital standard. This trend of subscriber evolution is even more apparent when one considers the eventual societal ramifications of video on demand (VOD), near-VOD (NVOD), and other on-demand “audience targeting” (e.g., billing, screening, selectivity, transactional) functionality. The fundamental NII element at issue here is broadband household “addressability” in the mass media environment of broadcast video networks (VD-2). Beginning with the addition of the ever increasing numbers of pay-per-view (PPV) channels that will eventually constitute NVOD, over the next 3 to 5 years cabled systems will continue to expand the commercial opportunities associated with VD-2 addressability. It is this addressability element and the efficiency of electronic distribution that will eventually attract the direct mail and advertising industry into the interactive multimedia (analog and digital) convergence. Also attracted will be the catalog shopping industry as a natural evolution of the switched telephone (i.e., 800-number service, VD-1) and broadcasted NTSC video (i.e., VHF, UHF, CATV, VD-2) TV home shopping industry. As the electronic publishing industry (i.e., audio, video, and multimedia programmers) converges on a single and fully integrated VD-3 or (VD-1 + VD-2) communications network, the concept of “the subscriber” will evolve from one of being either a VD-1 (i.e., telco) or VD-2 (i.e., CATV) subscriber to that of being a VD-3 subscriber more closely resembling an a la carte magazine subscriber in a “common carrier” postal distribution system.

I Have an Address . . . Therefore I Am

The bottom line is that the regulatory model for the NII must acknowledge the emergence of a new public utility network system that will eventually, among other things, enhance if not replace our national postal system and local systems of public and private libraries, bookstores, movie theaters, and video rental outlets. The NII is a public network that carries broadcasted (VD-2) and switched (VD-1) information and entertainment (i.e., electronic communications and publishing) to the “addressable households” of VD-3 (i.e., NII) subscribers.


Assuming a proper interactive video dialtone (VD-3) regulatory model for the encouragement of an NII with public utility potential, the services for these subscribers will have to come from someone. That someone will be those corporate and commercial entities investing in the necessary hardware, software, and “wetware” (i.e., R&D and other creative talents) for some given and recognized, regulated and unregulated, return on investment(s). This brings us back to PTN architecture and the technology deployment issues. The PTN hardware/software, regardless of architecture model (i.e., PC, TSB, DTMF-TV), for delivering and controlling the public utility potential of an information “flow” consists of the following elements:


  • “Pipes” (e.g., DS-0, ISDN, SONET, NTSC, and other transmission standards);

  • “Valves” (e.g., DXC, ATM, USPS—zip code, Bellcore administered—NPA—addressing plans; and other household routing and switching standards); and


  • “Reservoirs” of information (e.g., databases, film libraries, the Internet, the Library of Congress).

One must understand that the metaphor of an information superhighway (VD-1) is only half of the bigger public works picture. The NII (i.e., VD-3) is also an information superpower utility project (i.e., water, gas, electric light, sewage, VD-2).

Although their roles are still to be determined, these corporate entities (i.e., private sector investors) for the next decade or two will nevertheless consist of variations and combinations of LECs, IXCs, MSOs, broadcasters, publishers, and other agents. Their high-level PTN architecture will consist of the following elements:


  • “Dams” (i.e., technical, economic, regulatory, legislative, and licensing parameters) to channel the flow;

  • “Floodgates” (i.e., LEC COs, MSO head ends, and IXC POPs) to regulate, meter, and bill for the flow; and


  • “Generators” (i.e., networked computers) to serve the public with information and entertainment services.

The bottom line is that the dams and floodgates are PTN architectural “barriers and bottlenecks” that will control the flow of information and entertainment to the public. Consequently, the NII will need to provide for dams with equal-access floodgates and pipes.



Attracting the investment necessary to build this new public network, as in any public utility infrastructure project, will likely require grants of clearly defined market territories to licensed operators. The more exclusive the legal right to exclude nonlicensed competition in a given VD-3 subscriber serving area (SSA), the more attractive these pioneering PTN operators will become to long-term private sector investors. Hence, exclusivity will drive the private sector’s funding of the NII.



Our former Bell system had a simple but broad goal: a phone in every home that wanted one. Since the Communications Act of 1934, this natural monopoly public network was tasked with providing the public utility infrastructure necessary to permit any person in the United States to communicate with any other person in an affordable way. That goal, for its time, was enormously ambitious; but everyone, from planner to engineer, lineman to operator, clerk to executive, public consumer to regulator, intuitively understood it. It took half a century of dedicated work by telephone pioneers to achieve that goal of universal service.

The public sector should set a similar goal that will challenge the private sector to create a ubiquitous interactive multimedia common carrier system to serve the next two to four generations of Americans. That goal should include a public telecomputer network system harnessing the diversified and collective intelligence of our entire country for the public’s convenience, interest, and necessity.


In the same way that the public and private sector cooperated to develop a channel numbering plan for VHF (i.e., channels 2 through 13) and UHF VD-2 channels, nationwide VD-3 network operators will require a consistent and national CATV (i.e., community antenna TV) channel numbering plan. A video program on a broadband TV channel in one state should be on the same NII channel in any other state. This NII numbering plan should accommodate both the existing wireless and wireline broadcasters in a common carrier environment, provide for equal access by all information and entertainment generators, and reserve channel space for education and government. It should also make allowances for significant channel numbers (e.g., 411, 555, 800, 900, 911) that will assist the public in navigating a VD-3 world. Such a plan is needed to offer the public network channel surfers a “logical interface” to the 500+ channel systems of the relatively near future (see Reference 3 for plan proposal).


NII policy should also define the classes of (nondiscriminatory) VD-3 service. These classes in a common carrier environment of addressable VD-3 or (VD-1 + VD-2) households will consist of the classes permitted by combining the PSTN’s nationwide automatic number identification (ANI) capability with a numbering plan for the growing number of addressable broadband receivers in the PBN. With the coming evolution of video “mail,” the classes of service can, if not should, be modeled after those used in our postal system (see Reference 3 for plan proposal).


The PTN will consist of VD-3 network operators providing a public network of common carrier services to the next generation. The public and private sectors should jointly develop the criteria that will define a PTN public utility system. The criteria should set parameters that include demonstrating the inherent capability of the PTN architecture (i.e., PC, TSB, DTMF-TV) both to provide universal and affordable interactive multimedia access and to serve all of America’s communities in a nondiscriminatory fashion.


There is at least one enabling public utility technology (see Reference 4 for an example) that can deliver on the VD-3 universal access promise. The public sector may need to acknowledge that this form of public utility service, like all others before it, requires a “federal franchise” to operate as a regulated monopoly. Such a franchise will be required in order to attract the necessary capital to build an information superpower system. This approach worked before as the Bell system. With a pioneering spirit, it can work again for a new generation of Americans.


[1] Thompson, Jack. 1995. “The DTMF-TV Telecomputer Model Offers the Most Economical Approach to Interactive TV,” GNOSTECH Inc., Annandale, Va.


] Thompson, “The DTMF-TV Telecomputer Model,” 1995.


] “The Awakening 2.0,” the comments of GNOSTECH Incorporated to the FCC’s Proposed Rulemaking on Video Dialtone (Common Carrier Docket No. 87-266), 1991.


] United States Patent No. 5,236,199, “Interactive Media System and Telecomputing Method Using Telephone Keypad Signaling.”