standard extending support of a key communications tool for the deaf and hard
of hearing to IP-based networks was consented at a recent meeting of ITU-Tís
Study Group 16. The continued support of textphones (TTYs) as operators
increasingly shift to IP is important for the many thousands of users of these
announcement marks a key milestone in the development of what ITU terms Total
Conversation, that is the convergence of voice, video and text telephony.
standard known as ITU-T Recommendation V.151 relates to text over IP (ToIP).
ToIP is the transport of real-time text over IP networks. It differs from
instant messaging in that ToIP systems transmit bi-directionally, one character
at a time. This gives the user the feel of real-time communication, just like
voice or video systems that transport streaming media over IP.
services are available using a legacy textphone (TTY) which has long been the
preferred tool of the deaf and hard of hearing, an enabled IP phone or a PC-based
has an important role to play in the protection of text quality when
transported through IP networks, also offering the potential to enable
communication between earlier incompatible textphones from different regions.