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THE STANDARDS PROCESS AS A ROUTE TO UNIVERSAL DESIGN IN TELECOMMUNICATIONS: THE CASE OF V.18

Judith E. Harkins, Ph.D. Technology Assessment Program Gallaudet University Washington, D.C.

ABSTRACT

One approach to universal design is the incorporation of assistive technologies into the design of products sold to the general market. To achieve this type of accessible design feature in general products, the development of industry standards can be helpful.

This paper presents a case of standards development in the area of text telephony. In September, 1994, the International Telecommunications Union's Telecommunications Standardization Sector (ITU-T, formerly CCITT) approved Recommendation V.18, which specifies an interworking protocol between conventional computer modems and text telephones. Once implemented, V.18 will result in text telephone capacity in conventional modems. This capacity will greatly increase the opportunity for direct text telecommunication among deaf and hearing people, and will provide compatibility with text telephones of other countries. V.18 represents the fulfillment of a partnership among industry, researchers, and consumers.

BACKGROUND

People who are deaf use text-based methods of telephone conversation. The first device to gain widespread use by the deaf community was an adaptation of the teletypewriter, or TTY. The TTY network began in 1964 when Robert Weitbrecht, a deaf physicist, developed an acoustic coupler for transmitting over the telephone network the Baudot code used in teletype transmission. The TTY network gave deaf people significant relief from the barrier created by the voice telephone.

While the TTY network was growing in the deaf community, personal computers entered the market. The computer modem became a common component of computer workstations, as the emergence of bulletin boards, on-line services, and the Internet created useful applications for modems.

On the surface, it appeared that computer modems using ASCII protocols should replace Baudot TTYs, which represent a technological backwater. However, the situation is not so clear-cut. Baudot, although slow and implemented in half duplex, has a number of advantages over ASCII protocols for telephone conversation. Advantages include instantaneous connection and a carrierless mode that is tolerant of the voice environment, whereas ASCII protocols used in American TTYs disconnect upon significant disruption to the carrier. The embedded base of Baudot TTYs is quite large, numbering in the hundreds of thousands. Despite the growing availability of ASCII, deaf people have continued to use Baudot. Even today, no more than 5% of text telephone calls to telephone relay services are initiated in ASCII.

OBJECTIVE

Based on these factors, and based on the telecommunications industry's principle of accommodating the embedded base as technology evolves, an effort was begun to foster migration to ASCII without forcing consumers to abandon Baudot.

METHODS

Gallaudet University began by contacting the Telecommunication Industries Association (TIA) for assistance. TIA recommended Richard P. Brandt, chairman of the domestic TR-30 committee on modems and vice chairman of Study Group XIV of the ITU-T (formerly CCITT) on modems. The initial goal was to work with the domestic TTY industry to correct some difficulties with ASCII implementation in U.S. TTYs.

Gallaudet, in cooperation with the consumer group Telecommunications for the Deaf, Inc. (TDI), began hosting industry meetings at conventions of consumer associations. The process was handled outside any formal standards body; an earlier attempt by the Electronic Industries Association to standardize TTYs had failed, and the requirements of a formal process were impossible for us to satisfy. Included in the discussions were all domestic TTY manufacturers, manufacturers of TTY-accessible call-handling equipment for 911 centers, and companies operating telephone relay services. Considerable progress was made with identifying how ASCII should be implemented in American TTYs, but it was unclear whether industry would implement these recommendations. As stated previously, the ASCII feature in TTYs is not widely used by deaf people, and the market did not seem to justify re-engineering.

Brandt quickly recognized that the problem was, in fact, an international problem. Telecommunications standards are international standards, since they require connectivity among devices and networks from all countries.

Brandt initiated standards development by petitioning the U.S. Department of State. ITU-T Study Group XIV subsequently undertook the development of an interworking protocol between American text telephones and computer modems. Very soon the study was broadened to include text telephones from European countries. Several European countries had developed their own approaches to specialized text telephones in the late 1970s and early 1980s. In all, six different text telephone protocols--all incompatible with one another--are in operation in Europe. This situation poses a dilemma to those concerned with organizing a single European Union. Work on V.18 was eventually embraced by these countries as one possible route to a solution.

The development of the standard was an international collaborative process of researchers, computer scientists, standards experts, and consumers. Much of the collaboration was made possible by the Internet, which removed barriers of space, time, and disability. The document was revised many times between its initiation in 1992 and its adoption in 1994.

The involvement of technically knowledgeable American consumers, particularly Norman Williams of Gallaudet, was critically important to the process. U.S. deaf consumers and TTY manufacturers were kept informed via regular articles in consumer newsletters. Manufacturers also received all revisions to the standard, and continued to meet yearly for purposes of giving input, until V.18 was completed.

RESULTS

As noted above, the ITU-T approved V.18 in September of 1994. The key provisions are these:

  • a calling tone, which will speed the connection process and alert hearing people and automatic detectors to an incoming text telephone call;
  • prohibition of automatic disconnect, so that the caller has full control over call completion and disturbances caused by voice and call transfers will not terminate the call;
  • re-connection after loss of carrier, a feature required for situations in which calls are transferred;
  • a method of displaying line energy, to give the user a visual display showing line status;
  • conversion of codes used in text telephones internationally, including Baudot, Bell 103, DTMF, EDT, V.21, and V.23;
  • interworking specifications and flowcharts.

DISCUSSION

These observations may prove helpful to others seeking to employ the standards process to achieve improvements in universal design and compatibility with assistive technologies.

An international standard has the following advantages:

  • Dissemination of information to a large international industry is handled by industry's own channels. A wide variety of companies, from Hayes to Microsoft, were aware of V.18 without outreach from those involved in standards development.
  • Manufacturers from around the world have the opportunity to participate in standards development; much free technical assistance is provided during the development phases.
  • The standard may, at some future date, be incorporated into mandatory government standards. If this happens in Europe, the worldwide implementation of V.18 in commercial products will be assured.
  • The problem of incompatibility among the world's text telephones can be addressed.
  • The standards process has, of course, this important limitation: Adoption of the standard is entirely voluntary unless a government requires it of the industry. This rarely happens in the U.S. Although the word "standard" gives the impression that universal design is assured, this is not at all the case. By seeking the solution to a domestic problem, we ended up with a possible solution to both a domestic and an international problem. The project also paved the way for future telecommunications standards aimed at universal access. Once the standard was written, it became part of the culture of the standards groups, and greatly raised their awareness.

As is often the case in universal access efforts, the key to success was the interest and dedication of someone from the industry side willing to be a champion for the effort. Dick Brandt contributed most of the time spent working on V.18, and was fully dedicated to the project from beginning to end.

Funding was contributed from multiple sources. Government funding permitted researchers to be involved and contribute to the standard. Industry supported travel and Brandt's later work on V.18. Government grants are not generous enough to finance the kind of commitment in terms of travel and time that is required, and this could hamper future efforts unless industry stays involved.

CONCLUSION

The ultimate realization of the goal will be a widely adopted standard and effective products. More than a year has passed since V.18 was approved, and to date (December, 1995) there is no product on the market. Recently British Telecom has revealed development of a V.18 prototype; it is hoped this will lead to commercialization. As always, uncontrollable business decisions dictate the success or failure of any attempt at universal design.

It is hoped that V.18 products will take many forms, from modem cards to conventional TTYs. There is still a market for free-standing equipment in businesses and homes, and the assistive technology companies can still thrive by producing these devices.

The next challenge will be testing of prototypes and early products, in concert with deaf people in other countries, to ensure that V.18 serves the consumer as an effective TTY. Additional standards work will be needed to address the issue of character sets and other issues pertaining to international communications.

REFERENCES

1. International Telecommunications Union (1994). Recommendation V.18

2. Williams, N. S., Jensema, C. J., and Harkins, J. E. (1991). ASCII-based TDD products: features and compatibility. In J. L. Presperin (ed.), RESNA 91: Proceedings of the 14th Annual Conference. Washington, DC: RESNA Press, 41-43.

3. Burt, D., AT&T Accessible Communications, personal communication, December, 1995.

4. Olesen, K. G. (1992). Survey of Text Telephones and Relay Services in Europe. Luxembourg: Office for Official Publications of the European Communities.

5. Brandt, R. P. (1994). ITU-T Recommendation V.18: The first communications standard for the deaf. Technology and Disability, 3(3), 195-202.

ACKNOWLEDGMENTS

This work was supported by the U.S. Department of Education, National Institute on Disability and Rehabilitation Research, as part of a Rehabilitation Engineering Research Center on Technological Aids for the Deaf and Hard of Hearing (H133E80019), based at the Lexington Center. The funding support of dB Consulting, Inc., AT&T, and Gallaudet University is also gratefully acknowledged.

Judith E. Harkins, Ph.D. Gallaudet University 800 Florida Avenue, NE Washington, DC 20002 jeharkins@gallua.gallaudet.edu (202) 651-5257 (voice/TTY) (202) 651-5476 (fax)