V.18 Protocol
Have you ever tried to contact a person in another country using a
TTY? If so, you may already know that there are many different TTY
communication protocols currently in use throughout the world, and that
most of them are incompatible. So if you've always wanted to contact
your deaf friend in Italy via TTY, you may soon be able to.
The problem is that TTY technology has developed pretty much
independently in many different countries, and the current devices are
incompatible. The different technology part of the problem is not likely
to change soon, because Italy is no more likely to adopt the TTY
technology from the US than the US is to adopt theirs. The solution is
to develop a technology that provides communication between the
seemingly incompatible systems.
A protocol called V.18 does exactly that, and Ultratec has recently
announced a commercial implementation. Ultratec's Minicom Pro8000a
series TTYs, recently introduced in Great Britain, are V.18 compliant.
V.18 works by providing a negotiating framework within which two TTYs
can find a mutually agreeable protocol. This strategy is similar to the
way fax machines find a mutually compatible code.
Ultratec worked with a variety of experts and organizations to
develop a functional system for implementing the V.18 protocol into its
text telephones. Among the TTY codes they include is one called Turbo
Code(R), which makes their TTYs compatible with a majority of text
telephones and dual parity relay systems worldwide.